View:
Download DOC
Download PDF
Download XLS

QuickLinks -- Click here to rapidly navigate through this document

SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549

SCHEDULE TO
(RULE 13e-4)
TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1) OF
THE SECURITIES EXCHANGE ACT OF 1934
(Amendment No.            )

SPX CORPORATION
(Name of Subject Company (Issuer))

SPX CORPORATION
(Names of Filing Persons (identifying status as offeror, issuer or other person))

Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior)
(Title of Class of Securities)

784635 AF 1
(CUSIP Numbers of Class of Securities)

C. B. Richardson, Esq.
Assistant General Counsel
SPX Corporation
13515 Ballantyne Corporate Place
Charlotte, North Carolina 28277
(704) 752-4400
(Name, address, and telephone number of person
authorized to receive notices and communications on behalf of filing persons)

with copies to:

Stuart Gelfond, Esq.
Fried, Frank, Harris, Shriver & Jacobson LLP
One New York Plaza
New York, New York 10004
(212) 859-8000

CALCULATION OF FILING FEE

Transaction Valuation*: $17,861,070.50   Amount of Filing Fee**: $2,102.25
*
Calculated solely for purposes of determining the filing fee. The purchase price of the Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior), as described herein, is $645.97 per $1,000 principal amount at maturity outstanding. As of April 8, 2005, there was approximately $27,650,000 in aggregate principal amount at maturity outstanding, resulting in an aggregate maximum purchase price of $17,861,070.50.

**
The amount of the filing fee was calculated in accordance with Rule 0-11 of the Securities Exchange Act of 1934, as amended, and equals $117.70 for each $1,000,000 of the value of the transaction.

o
Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

Amount Previously Paid:   Not applicable   Filing Party:   Not applicable

Form or Registration No.:
 
Not applicable
 
Date Filed:
 
Not applicable
o
Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes to designate any transactions to which this statement relates:

o   third-party tender offer subject to Rule 14d-1.   o   going-private transaction subject to Rule 13e-3.

ý
 
issuer tender offer subject to Rule 13e-4.
 
o
 
amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: o


INTRODUCTORY STATEMENT

        This Tender Offer Statement on Schedule TO-I ("Schedule TO-I") is filed by SPX Corporation, a Delaware corporation (the "Company"), and relates to the offer by the Company to purchase the Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior) issued by the Company on May 9, 2001 (the "Securities"), upon the terms and subject to the conditions set forth in the Indenture (as defined below), the Company Notice, dated April 8, 2005 (the "Company Notice"), the Securities and the related offer materials filed as Exhibits (a)(1)(A) to (d)(2) to this Schedule TO-I (which Company Notice and related offer materials, as amended or supplemented from time to time, collectively constitute the "Option"). The Securities were issued pursuant to an Indenture, dated as of May 9, 2001, between the Company and JPMorgan Chase Bank, N.A. (as successor to The Chase Manhattan Bank), as Trustee ("Trustee") (the "Indenture").

        The Option will expire at 5:00 p.m., New York City time, on May 9, 2005. This Schedule TO-I is intended to satisfy the disclosure requirements of Rule 13e-4(c)(2) under the Securities Exchange Act of 1934, as amended (the "Exchange Act").


Items 1 through 9.

        The Company is the issuer of the Securities and is offering to purchase all of the Securities if tendered by the holders under the terms and subject to the conditions set forth in the Indenture, the Company Notice, the Securities and the related offer materials filed as Exhibits (a)(1)(A) to (d)(2). The Securities are convertible into shares of common stock, par value $10 per share, (including preferred stock purchase rights) of the Company. The Company maintains its registered and principal executive offices at 13515 Ballantyne Corporate Place, Charlotte, North Carolina 28277. The telephone number there is (704) 752-4400. As permitted by General Instruction F to Schedule TO, all of the information set forth in the Option is incorporated by reference into this Schedule TO-I.


Item 10. Financial Statements.

        (a)   The Company believes that its financial condition is not material to a holder's decision whether to put the Securities to the Company because the consideration being paid to holders surrendering Securities consists solely of cash, the Option is not subject to any financing conditions, the Option applies to all outstanding Securities and the Company is a public reporting company that files reports electronically on EDGAR. The financial condition and results of operations of the Company and its subsidiaries are reported electronically on EDGAR on a consolidated basis.

        (b)   Not applicable.


Item 11. Additional Information.

        (a)   Not applicable.

        (b)   Not applicable.


Item 12. Exhibits.

(a)(1)(A)   Company Notice to Holders of SPX Corporation Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior), dated April 8, 2005.

(a)(1)(B)
 
Form of Purchase Notice dated April 8, 2005.

(a)(1)(C)
 
Form of Notice of Withdrawal dated April 8, 2005.

(a)(1)(D)
 
Form W-9.

(a)(5)(A)
 
Press Release issued by SPX Corporation on April 8, 2005.
     

2


(b)
 
Not applicable.

(d)(1)
 
Indenture, dated as of May 9, 2001, between SPX Corporation and JPMorgan Chase Bank, N.A. (as successor to The Chase Manhattan Bank), incorporated by reference to Exhibit 4.1 to the Company's Registration Statement on Form S-3 (File No. 333-68648), as filed with the Securities and Exchange Commission on August 29, 2001.

(d)(2)
 
Indenture, dated as of February 6, 2001, between SPX Corporation and JPMorgan Chase Bank, N.A. (as successor to The Chase Manhattan Bank), incorporated by reference to Exhibit 4.1 to the Company's Registration Statement on Form S-3 (File No. 333-56364), as filed with the Securities and Exchange Commission on February 28, 2001.

(g)
 
Not applicable.

(h)
 
Not applicable.


Item 13. Information Required by Schedule 13E-3.

        (a)   Not applicable.

3


SIGNATURE

        After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

    SPX CORPORATION

 
 
By:
 
/s/  PATRICK J. O'LEARY      
    Name:   Patrick J. O'Leary
    Title:   Executive Vice President, Treasurer
and Chief Financial Officer

Dated: April 8, 2005

4


EXHIBIT INDEX

Exhibit No.
   Description
(a)(1)(A)   Company Notice to Holders of SPX Corporation Liquid Yield OptionTM Notes due May 9, 2021 (Zero Coupon-Senior), dated April 8, 2005.

(a)(1)(B)
 
Form of Purchase Notice dated April 8, 2005.

(a)(1)(C)
 
Form of Notice of Withdrawal dated April 8, 2005.

(a)(1)(D)
 
Form W-9.

(a)(5)(A)
 
Press Release issued by SPX Corporation on April 8, 2005.

(b)
 
Not applicable.

(d)(1)
 
Indenture, dated as of May 9, 2001, between SPX Corporation and JPMorgan Chase Bank, N.A., (as successor to The Chase Manhattan Bank), incorporated by reference to Exhibit 4.1 to the Company's Registration Statement on Form S-3 (File No. 333-68648), as filed with the Securities and Exchange Commission on August 29, 2001.

(d)(2)
 
Indenture, dated as of February 6, 2001, between SPX Corporation and JPMorgan Chase Bank, N.A. (as successor to The Chase Manhattan Bank), incorporated by reference to Exhibit 4.1 to the Company's Registration Statement on Form S-3 (File No. 333-56364), as filed with the Securities and Exchange Commission on February 28, 2001.

(g)
 
Not applicable.

(h)
 
Not applicable.



QuickLinks

INTRODUCTORY STATEMENT
SIGNATURE
EXHIBIT INDEX

QuickLinks -- Click here to rapidly navigate through this document

Exhibit (a)(1)(A)


COMPANY NOTICE
TO HOLDERS OF
SPX CORPORATION
LIQUID YIELD OPTION™ NOTES DUE MAY 9, 2021 (ZERO COUPON-SENIOR)

CUSIP Numbers: 784635 AF 1*

*
No representation is made with respect to the accuracy of the CUSIP number as printed on the Securities or as contained herein.

        NOTICE IS HEREBY GIVEN pursuant to the terms and conditions of the Indenture, dated as of May 9, 2001 (the "Indenture"), between SPX Corporation, a Delaware corporation (the "Company" or "SPX") and JPMorgan Chase Bank, N.A. (as successor to The Chase Manhattan Bank), a national banking association organized and existing under the laws of the United States of America as depositary (the "Depositary"), relating to the Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior) of the Company (the "Securities"), that at the option of the holder thereof (the "Holder"), the Securities will be purchased by the Company for $645.97 per $1,000 principal amount at maturity of the Securities (the "Purchase Price"), subject to the terms and conditions of the Indenture, the Securities and this Company Notice and related offer materials, as amended and supplemented from time to time (the "Option"). Holders may surrender their Securities from April 8, 2005, through 5:00 p.m., New York City time, on May 9, 2005. This Company Notice is being sent pursuant to the provisions of Section 3.08 of the Indenture and paragraph 7 of the Securities. All capitalized terms used but not specifically defined herein shall have the meanings given to such terms in the Indenture.

        To exercise your option to have the Company purchase the Securities and receive payment of $645.97 per $1,000 principal amount at maturity of the Securities ("$1,000 principal amount"), you must validly surrender the Securities and the enclosed Purchase Notice to the Depositary (and not have withdrawn such surrendered Securities and Purchase Notice), prior to 5:00 p.m., New York City time, on Monday, May 9, 2005 (the "Purchase Date"); Securities surrendered for purchase may be withdrawn at any time prior to 5:00 p.m., New York City time, on Monday, May 9, 2005. The right of Holders to surrender Securities for purchase in the Option expires at 5:00 p.m., New York City time, on Monday, May 9, 2005. HOLDERS THAT SURRENDER THROUGH THE DEPOSITORY TRUST COMPANY ("DTC") NEED NOT SUBMIT A PHYSICAL PURCHASE NOTICE TO THE DEPOSITARY IF SUCH HOLDERS COMPLY WITH THE TRANSMITTAL PROCEDURES OF DTC.

        The addresses for the Depositary are as follows:


By Facsimile Transmission Certified:
 
If by Overnight Courier or Hand:
 
If by Registered or Certified Mail:
JPMorgan Chase Bank, N.A.
(214) 468-6494
(For Eligible Institutions Only)
Attention: Frank Ivins		   JPMorgan Chase Bank, N.A.
ITS Bond Events
2001 Bryan Street, 9th Floor
Dallas, TX 75201		   JPMorgan Chase Bank, N.A.
ITS Bond Events
PO Box 2320
Dallas, TX 75221

        Copies of this Company Notice may be obtained from the Depositary at its addresses set forth above.

The date of this Company Notice is April 8, 2005.

TABLE OF CONTENTS

 
    
   Page
SUMMARY TERM SHEET   1
IMPORTANT INFORMATION CONCERNING THE OPTION   4
1.   Information Concerning the Company   4
2.   Information Concerning the Securities   4
  2.1.       The Company's Obligation to Purchase the Securities   4
  2.2.       Purchase Price   4
  2.3.       Conversion Rights of the Securities   5
  2.4.       Market for the Securities and SPX Common Stock   5
  2.5.       Redemption   6
  2.6.       Change in Control   6
  2.7.       Ranking   6
3.   Procedures to Be Followed by Holders Electing to Surrender Securities for Purchase   6
  3.1.       Method of Delivery   7
  3.2.       Purchase Notice   7
  3.3.       Delivery of Securities.   7
4.   Right of Withdrawal   8
5.   Payment for Surrendered Securities   8
6.   Securities Acquired   8
7.   Plans or Proposals of the Company   8
8.   Interests of Directors, Executive Officers and Affiliates of the Company in the Securities   9
9.   Purchases of Securities by the Company and Its Affiliates   10
10.   Material United States Tax Considerations.   10
11.   Additional Information   12
12.   No Solicitations   12
13.   Definitions   12
14.   Conflicts   13

        No person has been authorized to give any information or to make any representations other than those contained in this Company Notice and accompanying Purchase Notice and, if given or made, such information or representations must not be relied upon as having been authorized. This Company Notice and accompanying Purchase Notice do not constitute an offer to buy or the solicitation of an offer to sell securities in any circumstances or jurisdiction in which such offer or solicitation is unlawful. The delivery of this Company Notice shall not under any circumstances, create any implication that the information contained herein is current as of any time subsequent to the date of such information. None of the Company or its board of directors or employees are making any representation or recommendation to any Holder as to whether or not to surrender such Holder's Securities. You should consult your own financial and tax advisors and must make your own decision as to whether to surrender your Securities for purchase and, if so, the amount of Securities to surrender.

i

SUMMARY TERM SHEET

        The following are answers to some of the questions that you may have about the Option. To understand the Option fully and for a more complete description of the terms of the Option, we urge you to read carefully the remainder of this Company Notice and the accompanying Purchase Notice because the information in this summary is not complete and those documents contain additional important information. We have included page references to direct you to a more complete description of the topics in this summary.

        SPX Corporation, a Delaware corporation (the "Company"), is offering to purchase your validly surrendered Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior) (the "Securities"). (Page 4)

        We are offering to purchase all of the Securities surrendered, at the option of the holder thereof (the "Holder"). As of April 8, 2005, there was approximately $27,650,000 aggregate principal amount at maturity of Securities outstanding. The Securities were issued under an Indenture, dated as of May 9, 2001 (the "Indenture"), between the Company and JPMorgan Chase Bank, N.A. (as successor to The Chase Manhattan Bank), a national banking association organized and existing under the laws of the United States of America (the "Depositary"). (Page 4)

        Pursuant to the terms of the Indenture, we will pay, in cash, a purchase price of $645.97 per $1,000 principal amount at maturity of the Securities (the "Purchase Price") with respect to any and all Securities validly surrendered for purchase and not withdrawn. (Page 4)

        There is no established reporting system or market for trading in the Securities. To the extent that the Securities are traded, prices of the Securities may fluctuate widely depending on trading volume, the balance between buy and sell orders, prevailing interest rates, the Company's operating results and the market for similar securities. To the extent available, Holders are urged to obtain current market quotations for the Securities prior to making any decision with respect to the Option. The Common Stock, $10 par value per share (the "Common Stock") of SPX into which the Securities are convertible is listed on the NYSE and the Pacific Stock Exchange under the symbol "SPW". On April 7, 2005, the last reported sales price of the Common Stock on the NYSE was $42.40 per share. (Pages 5-6)

        The Company is required to make the offer pursuant to the terms of the Securities and the Indenture. (Page 4)

        Although the board of directors for the Company has approved the terms of the Option included in the Indenture, the board of directors for the Company has not made any recommendation as to whether you should surrender your Securities for purchase in the offer. You must make your own decision whether to surrender your Securities for purchase in the offer and, if so, the amount of Securities to surrender. (Page 5)

1

        The Option expires at 5:00 p.m., New York City time, on May 9, 2005. The Company will not extend the period Holders have to accept the Option unless required to do so by the federal securities laws. (Page 4)

        The purchase by the Company of validly surrendered Securities is not subject to any conditions other than such purchase being lawful. (Page 4)

        To surrender your Securities for purchase pursuant to the Option, you must deliver the required documents to the Depositary no later than 5:00 p.m., New York City time, on May 9, 2005.

HOLDERS THAT SURRENDER THROUGH THE DEPOSITORY TRUST COMPANY ("DTC") NEED NOT SUBMIT A PHYSICAL PURCHASE NOTICE TO THE DEPOSITARY IF SUCH HOLDERS COMPLY WITH THE TRANSMITTAL PROCEDURES OF DTC.

        We will accept for payment all validly surrendered Securities promptly upon expiration of the Option. We will promptly forward to the Depositary, prior to 10:00 a.m., New York City time, on May 9, 2005, the appropriate amount of cash required to pay the Purchase Price for the surrendered Securities, and the Depositary will promptly distribute the cash to the Holders. (Pages 8)

        You can withdraw Securities previously surrendered for purchase at any time until 5:00 p.m., New York City time, on May 9, 2005. Securities not accepted for payment after the expiration of forty business days from the commencement of the offer to purchase the Securities may be withdrawn. (Page 8)

2

        To withdraw previously surrendered Securities, you must deliver an executed written notice of withdrawal substantially in the form attached, or a facsimile of one, to the Depositary prior to 5:00 p.m., New York City time, on May 9, 2005.

HOLDERS THAT WITHDRAW THROUGH DTC NEED NOT SUBMIT A PHYSICAL NOTICE OF WITHDRAWAL TO THE DEPOSITARY IF SUCH HOLDERS COMPLY WITH THE WITHDRAWAL PROCEDURES OF DTC. (Page 8)

        No. If you do not deliver a properly completed and duly executed Purchase Notice before the expiration of the Option, we will not purchase your Securities and such Securities will remain outstanding subject to their existing terms. (Page 6-7)

        No. You may surrender all of your Securities, a portion of your Securities or none of your Securities for purchase. If you wish to surrender a portion of your Securities for purchase, however, you must surrender your Securities in a principal amount at maturity of $1,000 (the "$1,000 principal amount") or an integral multiple thereof. (Page 6)

        Yes. If you do not surrender your Securities for purchase, your conversion rights will not be affected. You will continue to have the right to convert each $1,000 principal amount at maturity of a Security into 8.8588 shares of Common Stock (including preferred stock purchase rights) of SPX, subject to the terms, conditions and adjustments specified in the Indenture. (Page 5)

        The receipt of cash in exchange for Securities pursuant to the Option will be a taxable transaction for U.S. federal income tax purposes and you may recognize gain, income, loss or deduction. You should consult with your own tax advisor regarding the actual tax consequences to you. (Page 10-12)

        The JPMorgan Chase Bank, N.A., the trustee for the Securities, is serving as Depositary in connection with the Option. Its address and telephone number are set forth on the front cover page of this Company Notice. (Page 4)

        Questions and requests for assistance in connection with the surrender of Securities for purchase in this Option may be directed to JPMorgan Chase Bank, N.A. at (800) 275-2048.

3

IMPORTANT INFORMATION CONCERNING THE OPTION

        1.    Information Concerning the Company.    SPX Corporation, a Delaware corporation (the "Company", "SPX", "we", "us" or "our"), is offering to purchase its Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior) (the "Securities").

        SPX is a global multi-industry company that is focused on profitably growing a number of platform businesses that have scale and growth potential. SPX is a global provider of thermal equipment and services, flow technology, test and measurement solutions and industrial products and services. SPX offers a diverse collection of products, which include, but are not limited to, cooling towers, air filtration products, valves, back-flow prevention and fluid handling equipment, metering and mixing solutions, specialty services tools, diagnostic systems, service equipment and technical information services, power transformers, high-tech die castings, dock products and systems, and TV and radio broadcast antennae and towers. Its products are used by a broad array of customers in various industries, including automotive, chemical processing, pharmaceuticals, infrastructure, mineral processing, petrochemical, telecommunications, transportation and power generation. SPX operates in over 20 countries and, as of December 31, 2005, had approximately 23,800 employees worldwide, which includes 5,700 employees related to businesses classified in its financial statements as "discontinued operations."

        SPX maintains its registered and principal executive offices at 13515 Ballantyne Corporate Place, Charlotte, North Carolina 28277. The telephone number there is (704) 752-4400.

        2.    Information Concerning the Securities.    The Securities were issued under an Indenture, dated as of May 9, 2001 (the "Indenture"), between the Company and JPMorgan Chase Bank, N.A. (as successor to The Chase Manhattan Bank), a national banking association organized and existing under the laws of the United States of America (the "Depositary"). The Securities mature on May 9, 2021.

        2.1.    The Company's Obligation to Purchase the Securities.    Pursuant to the terms of the Securities and the Indenture, unless earlier redeemed, the Company is obligated to purchase all Securities validly surrendered for purchase and not withdrawn, at the Holder's option on May 9, 2005 and May 9, 2009. The purchase price will be $645.97 per LYON on May 9, 2005 and $720.55 per LYON on May 9, 2009.

        This Option will expire at 5:00 p.m., New York City time, on May 9, 2005 (the "Purchase Date"). The Company will not extend the period Holders have to accept the Option unless required to do so by the federal securities laws. The purchase by the Company of validly surrendered Securities is not subject to any conditions other than such purchase being lawful.

        2.2.    Purchase Price.    Pursuant to the Indenture, the purchase price to be paid by the Company for the Securities on May 9, 2005 is $645.97 per $1,000 principal amount at maturity of the Securities (the "Purchase Price"). The Purchase Price will be paid in cash with respect to any and all Securities validly surrendered for purchase and not withdrawn prior to the Purchase Date. Securities surrendered for purchase will be accepted only in principal amounts at maturity equal to $1,000 (the "$1,000 principal amount") or integral multiples thereof. The Original Issue Discount (as defined in the Indenture) will cease to accrue on the Purchase Date unless the Company defaults in making payment on Securities validly surrendered for purchase and not withdrawn.

        The Purchase Price is based solely on the requirements of the Indenture and the Securities and bears no relationship to the market price of the Securities or the Common Stock. Thus, the Purchase Price may be significantly higher or lower than the current market price of the Securities. Holders of Securities are urged to obtain the best available information as to potential current market prices of the Securities, to the extent available, and the Common Stock before making a decision whether to surrender their Securities for purchase.

4


        None of the Company or its board of directors or employees are making any recommendation to Holders as to whether to surrender or refrain from surrendering Securities for purchase pursuant to this Company Notice. Each Holder must make his or her own decision whether to surrender his or her Securities for purchase and, if so, the principal amount of Securities to surrender based on such Holder's assessment of current market value of the Securities and the Common Stock and other relevant factors.

        2.3.    Conversion Rights of the Securities.    The Securities are convertible into SPX Common Stock (including preferred stock rights) in accordance with and subject to the terms of the Indenture and paragraphs 9 and 10 of the Securities. The conversion rate of the Securities as of May 9, 2005 is 8.8588 shares of Common Stock (including preferred stock purchase rights) per $1,000 principal amount of the Securities. The Depositary is currently acting as Conversion Agent for the Securities.

        Holders that do not surrender their Securities for purchase pursuant to the Option will maintain the right to convert their Securities into Common Stock (including preferred stock purchase rights), subject to the terms, conditions and adjustments specified in the Indenture. Any Securities as to which a Purchase Notice has been given may be converted in accordance with the terms of the Indenture only if the applicable Purchase Notice has been validly withdrawn prior to 5:00 p.m., New York City time, on the Purchase Date, as described in Section 4 hereto.

        2.4.    Market for the Securities and SPX Common Stock.    There is no established reporting system or trading market for trading in the Securities. However, we believe the Securities currently are traded over the counter. We have been advised that there is no practical way to determine the trading history of the Securities. We believe that trading in the Securities has been limited and sporadic. To the extent that the Securities are traded, prices of the Securities may fluctuate widely depending on trading volume, the balance between buy and sell orders, prevailing interest rates, the Company's operating results and the market for similar securities. Following the consummation of the offer, we expect that Securities not purchased in the offer will continue to be traded over the counter; however, we anticipate that the trading market for the Securities will be even more limited. A debt security with a smaller outstanding principal amount available for trading (a smaller "float") may command a lower price and trade with greater volatility than would a comparable debt security with a larger float. Consequently, our purchase of Securities pursuant to the offer will reduce the float and may negatively affect the liquidity, market value and price volatility of the Securities that remain outstanding following the offer. We cannot assure you that a market will exist for the Securities following the offer. The extent of the public market for the Securities following consummation of the offer will depend upon, among other things, the remaining outstanding principal amount at maturity of the Securities at such time, the number of holders of Securities remaining at that time and the interest on the part of securities firms in maintaining a market in the Securities. The Securities are held through the Depository Trust Company ("DTC"). As of April 8, 2005, there was approximately $27,650,000 aggregate principal amount at maturity of Securities outstanding and DTC was and is the sole record holder of the Securities.

        The Common Stock of SPX into which the Securities are convertible is listed on the NYSE and the Pacific Stock Exchange under the symbol "SPW." The following table sets forth, for the fiscal quarters indicated, the high and low sales prices of the Common Stock as reported on the NYSE. This table gives effect to the October 24, 2002 two-for-one split of the Common Stock of SPX. In December 2003, the board of directors for the Company approved the implementation of a quarterly dividend program that began in 2004. Pursuant to the program, the Company expects to declare a quarterly dividend payable early in each fiscal quarter. The first dividend payment was paid early in the second quarter 2004. The board of directors for the Company approved an initial target quarterly dividend level of $0.25 per share. The actual amount of each quarterly dividend, as well as each declaration date, record date and payment date, is subject to the discretion of the board of directors for the Company, and the target dividend level may be adjusted during the year at the discretion of the

5


board of directors for the Company. The factors the board of directors for the Company are expected to consider in determining the actual amount of each quarterly dividend will include the Company's financial performance and on-going capital needs, its ability to declare and pay dividends under the terms of its credit facility and indenture, and other factors deemed relevant.

 
   High
   Low
2005            
  2nd Quarter (through April 7, 2005)   $ 43.42     41.12
  1st Quarter     47.90     37.85
2004            
  4th Quarter   $ 46.80     35.34
  3rd Quarter     46.51     32.46
  2nd Quarter     49.50     40.92
  1st Quarter     63.16     41.51
2003            
  4th Quarter   $ 59.16   $ 43.70
  3rd Quarter     51.49     41.07
  2nd Quarter     45.40     30.73
  1st Quarter     41.40     31.35

        On April 7, 2005, the last reported sales price of the Common Stock on the NYSE was $42.40 per share. As of such date, there were approximately 75,181,196 shares of Common Stock outstanding. We urge you to obtain current market information for the Securities, to the extent available, and the Common Stock before making any decision to surrender your Securities pursuant to the Option.

        2.5.    Redemption.    The Securities are not redeemable by the Company prior to May 9, 2005. Beginning on May, 2005, the Securities are redeemable for cash at any time at the option of the Company, in whole or in part, at a redemption price equal to the Issue Price (as defined in the Indenture) plus accrued Original Issue Discount (as defined in the Indenture and as provided for in the Securities) to the date of redemption.

        2.6.    Change in Control.    The Holder may require the Company to redeem his or her securities if there is a Change in Control (as defined in the Indenture) at a redemption price equal to the Issue Price (as defined in the Indenture) plus accrued Original Issue Discount (as defined in the Indenture) to the date of redemption.

        2.7.    Ranking.    The Securities are unsecured and unsubordinated obligations of the Company. The Securities rank equal in right of payment with all of the Company's existing and future unsecured and unsubordinated indebtedness. The Securities are effectively subordinated to all existing and future indebtedness and other liabilities of the Company's subsidiaries and to the Company's obligations that are secured to the extent of the security, including the indebtedness under the Company's amended and restated credit agreement.

        3.    Procedures to Be Followed by Holders Electing to Surrender Securities for Purchase.    Holders will not be entitled to receive the Purchase Price for their Securities unless they validly surrender and do not withdraw the Securities on or before 5:00 p.m., New York City time, on the Purchase Date. Only registered Holders are authorized to surrender their Securities for purchase. Holders may surrender some or all of their Securities; however, any Securities surrendered must be in $1,000 principal amount or an integral multiple thereof.

        If Holders do not validly surrender their Securities on or before 5:00 p.m., New York City time, on May 9, 2005, their Securities will remain outstanding subject to the existing terms of the Securities.

6


        3.1.    Method of Delivery.    The method of delivery of Securities, the related Purchase Notice and all other required documents, including delivery through DTC and acceptance through DTC's Automatic Tenders over the Participant Terminal System ("PTS"), is at the election and risk of the person surrendering such Securities and delivering such Purchase Notice and, except as expressly otherwise provided in the Purchase Notice, delivery will be deemed made only when actually received by the Depositary. The date of any postmark or other indication of when a Security or the Purchase Notice was sent will not be taken into account in determining whether such materials were timely received. If such delivery is by mail, it is suggested that Holders use properly insured, registered mail with return receipt requested, and that Holders mail the required documents sufficiently in advance of the Purchase Date to permit delivery to the Depositary prior to 5:00 p.m., New York City time, on May 9, 2005.

        3.2.    Purchase Notice.    Pursuant to the Indenture, the Purchase Notice must contain:

        3.3.    Delivery of Securities.    

        Securities in Certificated Form.    To receive the Purchase Price, Holders of Securities in certificated form must deliver to the Depositary the Securities to be surrendered for purchase and the accompanying Purchase Notice, or a copy thereof, on or before 5:00 p.m., New York City time, on the Purchase Date.

        Securities Held Through a Custodian.    A Holder whose Securities are held by a broker, dealer, commercial bank, trust company or other nominee must contact such nominee if such Holder desires to surrender his or her Securities and instruct such nominee to surrender the Securities for purchase on the Holder's behalf.

        Securities in Global Form.    A Holder who is a DTC participant, may elect to surrender to the Company his or her beneficial interest in the Securities by:

        Securities and the Purchase Notice must be delivered to the Depositary to collect payment. Delivery of documents to DTC or the Company does not constitute delivery to the Depositary.

HOLDERS THAT SURRENDER THROUGH DTC NEED NOT SUBMIT A PHYSICAL PURCHASE NOTICE TO THE DEPOSITARY IF SUCH HOLDERS COMPLY WITH THE TRANSMITTAL PROCEDURES OF DTC.

7


        4.    Right of Withdrawal.    Securities surrendered for purchase may be withdrawn at any time prior to 5:00 p.m., New York City time, on the Purchase Date. In order to withdraw Securities, Holders must deliver to the Depositary written notice, substantially in the form enclosed herewith, containing:

        The signature on the notice of withdrawal must be guaranteed by an Eligible Guarantor Institution (as defined in Rule 17Ad-15 of the Exchange Act) unless such Securities have been surrendered for purchase for the account of an Eligible Guarantor Institution. Any properly withdrawn Securities will be deemed not validly surrendered for purposes of the Option. Securities withdrawn from the Option may be resurrendered by following the surrender procedures described in Section 3 above. Securities not accepted for payment after the expiration of forty business days from the commencement of the offer to purchase the Securities may be withdrawn.

HOLDERS THAT WITHDRAW THROUGH DTC NEED NOT SUBMIT A PHYSICAL NOTICE OF WITHDRAWAL TO THE DEPOSITARY IF SUCH HOLDERS COMPLY WITH THE WITHDRAWAL PROCEDURES OF DTC.

        5.    Payment for Surrendered Securities.    We will promptly forward to the Depositary, prior to 10:00 a.m., New York City time, on May 9, 2005 the appropriate amount of cash required to pay the Purchase Price for the surrendered Securities, and the Depositary will promptly distribute the cash to each Holder that has validly delivered its Securities and not validly withdrawn such delivery prior to 5:00 p.m., New York City time, on the Purchase Date.

        The total amount of funds required by the Company to purchase all of the Securities is approximately $17.9 million (assuming all of the Securities are validly surrendered for purchase and accepted for payment). In the event any Securities are surrendered and accepted for payment, the Company intends to use cash to purchase the Securities. The Company does not have an alternative financing plan at this time.

        6.    Securities Acquired.    Any Securities purchased by the Company pursuant to the Option will be cancelled by the Trustee, pursuant to the terms of the Indenture.

        7.    Plans or Proposals of the Company.    Other than as publicly disclosed or as described below, the Company currently has no plans which would be material to a Holder's decision to surrender Securities for purchase in the Option, which relate to or which would result in:

8


        On March 16, 2005 the Company announced that Ross B. Bricker would become Senior Vice President, Secretary and General Counsel of the Company effective as of April 11, 2005.

        8.    Interests of Directors, Executive Officers and Affiliates of the Company in the Securities.    Except as otherwise disclosed below, to the knowledge of the Company:

        A list of the directors and executive officers of SPX is attached to this Company Notice as Annex A.

        On February 6, 2001, pursuant to the Indenture dated as of February 6, 2001, between the Company and The Chase Manhattan Bank, as Trustee, the Company issued Liquid Yield Option™ Notes ("February LYONs") at an original price of $579.12 per $1,000 principal amount at maturity, which represents an aggregate initial issue price of $576.1 million and an aggregate principal amount of $994.8 million due at maturity on February 6, 2021. The Company may redeem all or a portion of the February LYONs for cash at any time on or after February 6, 2006 at predetermined redemption prices. February LYONs holders may require the Company to purchase all or a portion of their February LYONs on February 6, 2006 for $663.86 per February LYON or February 6, 2011 for $761.00 per February LYON. In such case, the Company may choose to pay the purchase price for the February LYONs in cash, shares of Common Stock or a combination of cash and Common Stock.

        Except as described above, none of the Company, or to its knowledge, any of its affiliates, directors or executive officers, is a party to any contract, arrangement, understanding or agreement with any other person relating, directly or indirectly, to the Option or with respect to any of its securities, including, but not limited to, any contract, arrangement, understanding or agreement concerning the transfer or the voting of the securities, joint ventures, loan or option arrangements, puts or calls, guarantees of loans, guarantees against loss or the giving or withholding of proxies, consents or authorizations.

9


        9.    Purchases of Securities by the Company and Its Affiliates.    Each of the Company and its affiliates, including their executive officers and directors, are prohibited under applicable United States federal securities laws from purchasing Securities (or the right to purchase Securities) other than through the Option until at least the tenth business day after the Purchase Date. Following such time, if any Securities remain outstanding, the Company and its respective affiliates may purchase Securities in the open market, in private transactions, through a subsequent tender offer, or otherwise, any of which may be consummated at purchase prices higher or lower than the Purchase Price. Any decision to purchase Securities after the Option, if any, will depend upon many factors, including the market price of the Securities, the amount of Securities surrendered for purchase pursuant to the Option, the market price of the Common Stock, the business and financial position of the Company, and general economic and market conditions.

        10.    Material United States Tax Considerations.    

        U.S. Federal Income Tax Considerations.    The following discussion is a summary of the material U.S. federal income tax considerations relating to the surrender of Securities for purchase pursuant to the Option. This discussion does not purport to be a complete analysis of all potential tax effects of the Option. This summary is based upon laws, regulations, rulings and decisions currently in effect, all of which are subject to change or differing interpretations at any time, possibly with retroactive effect. Moreover, this summary applies only to Holders who hold Securities as "capital assets" within the meaning of Section 1221 of the Internal Revenue Code of 1986, as amended (the "Code"), and does not purport to deal with persons in special tax situations, such as financial institutions, insurance companies, regulated investment companies, tax exempt investors, dealers in securities and currencies, U.S. expatriates, persons holding Securities as a position in a "straddle," "hedge," "conversion" or other integrated transaction for tax purposes, persons who own, directly or indirectly, 10% or more of SPX's voting power, or U.S. Holders (as defined below) whose functional currency is not the U.S. dollar. Further, this discussion does not address the consequences under U.S. federal estate or gift tax laws or the laws of any U.S. state or locality or any foreign jurisdiction.

        For purposes of this discussion, a "U.S. Holder" means a beneficial owner of Securities that is, for U.S. federal income tax purposes: a citizen or resident of the United States as defined in Section 7701 of the Code; a corporation (or other entity treated as a corporation for U.S. federal income tax purposes) created or organized in or under the laws of the United States or any political subdivision thereof; an estate the income of which is subject to U.S. federal income tax regardless of its source; a trust if a court within the United States is able to exercise primary jurisdiction over its administration and one or more U.S. persons have authority to control all of its substantial decisions. As used herein, the term "non-U.S. Holder" means a beneficial owner of Securities, other than a partnership, that is not a U.S. Holder as defined above. The tax treatment of a partnership that holds Securities will generally depend on the status of the partners and the activities of the partnership. Holders that are partnerships should consult their own tax advisors about the U.S. federal income tax consequences of surrendering Securities pursuant to the Option.

        Sale of Securities Pursuant to the Option.    A U.S. Holder who receives cash in exchange for Securities pursuant to the Option will recognize taxable gain or loss equal to the difference between (i) the amount of cash received, and (ii) the U.S. Holder's adjusted tax basis in the Securities surrendered.

        A U.S. Holder will have an adjusted tax basis in the Securities that will generally be equal to the U.S. Holder's purchase price of the Securities, increased by any interest income previously accrued by the U.S. Holder, and increased or decreased by the amount of any positive or negative adjustment, respectively, that a U.S. holder has made as a result of a purchase of a Security for an amount other than the adjusted issue price, all as determined under the special regulations governing contingent payment debt instruments (the "CPDI regulations"). Under the CPDI regulations, the adjusted issue

10


price is the issue price of a Security increased by any interest income that has accrued with respect to the Security since the issuance of the Security, determined without regard to any adjustment described above. The issue price of a Security is the first price at which a substantial amount of the Securities were sold to the public, excluding bond houses, brokers or similar persons or organizations acting in the capacity of underwriters, placement agents or wholesalers.

        The CPDI regulations are complicated. Each Holder should consult a tax adviser regarding the accrual of interest, any positive and negative adjustments, and the calculation of adjusted tax basis with respect to each Holder's Securities.

        Gain recognized upon the surrender of Securities for cash pursuant to the Option will generally be treated as ordinary interest income; any loss will be ordinary loss to the extent of interest previously included in income, and thereafter, capital loss (which will be long-term if the Securities are held for more than one year). The deductibility of net capital losses by individuals and corporations is subject to limitations.

        A non-U.S. Holder who receives cash in exchange for Securities pursuant to the Option generally will not be subject to U.S. federal income tax on any gain recognized, provided that: (i) such non-U.S. Holder does not own, actually or constructively, 10 percent or more of the total combined voting power of all classes of the Company's stock entitled to vote for purposes of Section 871(h)(3) of the Code, is not a controlled foreign corporation related, directly or indirectly, to the Company through stock ownership, and is not a bank receiving interest described in section 881(c)(3)(A) of the Code; (ii) the non U.S. Holder certifies on IRS Form W-8BEN, under penalties of perjury, that it is not a United States person and provides its name and address; (iii) such non-U.S. Holder is not an individual who is present in the United States for 183 days or more in the taxable year of disposition, or such individual does not have a "tax home" (as defined in section 911(d)(3) of the Code) or an office or other fixed place of business in the United States; and (iv) such gain is not effectively connected with the conduct by such non-U.S. Holder of a trade or business in the United States.

        If a non-U.S. Holder of the Securities is engaged in a trade or business in the United States, and if the gain on the notes is effectively connected with the conduct of such trade or business, and, if required by an applicable tax treaty, the gain is attributable to a United States "permanent establishment" maintained by such non-U.S. Holder, the non-U.S. Holder, although exempt from the withholding tax discussed in the preceding paragraphs, will generally be subject to regular U.S. federal income tax on any gain realized on the sale or exchange of the Securities in the same manner as if it were a U.S. Holder. In lieu of the certificate described in the preceding paragraph, such a non-U.S. Holder will be required to provide to the withholding agent a properly executed IRS Form W-8ECI (or successor form) in order to claim an exemption from withholding tax. In addition, if such a non-U.S. Holder is a foreign corporation, such Holder may be subject to a branch profits tax equal to 30% (or such lower rate provided by an applicable treaty) of its effectively connected earnings and profits for the taxable year, subject to certain adjustments.

        Backup Withholding.    Under the backup withholding provisions of the Code, a U.S. Holder who surrenders Securities for purchase will generally be subject to backup withholding at the rate of 28% of any gross payment if such Holder fails to provide properly completed Form W-9 (or other acceptable substitute). U.S. Holders electing to surrender Securities should complete the Form W-9 which is part of the Purchase Notice and provide it with the Securities being surrendered. If you are a U.S. Holder exempt from backup withholding under the Code, please so indicate in the Form W-9. If a non-U.S. Holder holds Securities through the non-U.S. office of a non-U.S. related broker or financial institution, backup withholding and information reporting generally will not be required. Information reporting, and possibly backup withholding, may apply if the Securities are held by a non-U.S. Holder through a U.S. broker or financial institution or the U.S. office of a non-U.S. broker or financial institution and the non-U.S. Holder fails to provide appropriate information (on Form W-8BEN or

11


other applicable form). Non-U.S. Holders should consult their tax advisors with respect to the application of U.S. information reporting and backup withholding rules to the disposition of Securities pursuant to the Option.

        All descriptions of tax considerations are for Holders' guidance only and are not tax advice. The Company recommends that Holders consult with their tax and financial advisors with respect to the tax consequences of surrendering Securities for purchase, including the applicability and effect of state, local and foreign tax laws, before surrendering their Securities for purchase.

        11.    Additional Information.    SPX is subject to the reporting and other informational requirements of the Exchange Act and, in accordance therewith, files reports, proxy statements and other information with the SEC. Such reports, proxy statements and other information can be inspected and copied at the Public Reference Section of the SEC located at Room 1024, Judiciary Plaza, 450 Fifth Street, N.W., Washington D.C. 20549. Copies of such material can be obtained from the Public Reference Section of the SEC at prescribed rates. Such material may also be accessed electronically by means of the SEC's home page on the Internet at www.sec.gov. Such reports and other information concerning SPX may also be inspected at the offices of the NYSE located at 20 Broad Street, New York, New York 10005 and at the offices of the Pacific Stock Exchange located at 115 Sansome Street, San Francisco, California 94104.

        The Company has filed with the SEC a Tender Offer Statement on Schedule TO-I, pursuant to Section 13(e)(4) of the Exchange Act and Rule 13e-4 promulgated thereunder, furnishing certain information with respect to the Option. The Tender Offer Statement on Schedule TO-I, together with any exhibits and any amendments thereto, may be examined and copies may be obtained at the same places and in the same manner as set forth above.

        The documents listed below (as such documents may be amended from time to time) contain important information about the Company and its financial condition.

        In the event of conflicting information in these documents, the information in the latest filed documents should be considered correct.

        12.    No Solicitations.    The Company has not employed any persons to make solicitations or recommendations in connection with the Option.

        13.    Definitions.    All capitalized terms used but not specifically defined herein shall have the meanings given to such terms in the Indenture.

12


        14.    Conflicts.    In the event of any conflict between this Company Notice and the accompanying Purchase Notice on the one hand and the terms of the Indenture or any applicable laws on the other hand, the terms of the Indenture or applicable laws, as the case may be, will control.

        None of the Company or its board of directors or employees are making any recommendation to any Holder as to whether to surrender or refrain from surrendering Securities for purchase pursuant to this Company Notice. Each Holder must make his or her own decision whether to surrender his or her Securities for purchase and, if so, the principal amount of Securities to surrender based on their own assessment of current market value and other relevant factors.

    SPX CORPORATION

April 8, 2005

13

ANNEX A

BOARD OF DIRECTORS AND EXECUTIVE OFFICERS

        The following table sets forth the names of each of the members of SPX's board of directors and each of SPX's executive officers.

Name
   Position(s) Held
Charles E. Johnson II   Chairman of the Board
Christopher J. Kearney   President, Chief Executive Officer and Director
Patrick J. O'Leary   Executive Vice President, Treasurer and Chief Financial Officer
Ross B. Bricker   Senior Vice President, Secretary and General Counsel*
Robert B. Foreman   Senior Vice President, Human Resources
Jay Caraviello   Executive Vice President and Co-Chief Operating Officer
Thomas J. Riordan   Executive Vice President and Co-Chief Operating Officer
J. Kermit Campbell   Director
Emerson U. Fullwood   Director
Sarah R. Coffin   Director
Michael J. Mancuso   Director
David P. Williams   Director
*
Effective April 11, 2005.

        The business address of each person set forth above is c/o SPX Corporation, 13515 Ballantyne Corporate Place, Charlotte, North Carolina 28277. The telephone number there is (704) 752-4400.

14



QuickLinks

COMPANY NOTICE TO HOLDERS OF SPX CORPORATION LIQUID YIELD OPTION™ NOTES DUE MAY 9, 2021 (ZERO COUPON-SENIOR)

QuickLinks -- Click here to rapidly navigate through this document

Exhibit (a)(1)(B)


PURCHASE NOTICE
TO SURRENDER
SPX CORPORATION
LIQUID YIELD OPTION™ NOTES DUE FEBRUARY 6, 2021
(ZERO COUPON-SENIOR)

CUSIP Numbers: 784635 AF 1*

*
No representation is made with respect to the accuracy of the CUSIP number as printed on the Securities or as contained herein.

Pursuant to the Company Notice
Dated April 8, 2005

        This Purchase Notice relates to the purchase of Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior) (the "Securities") of SPX Corporation, a Delaware corporation (the "Company" or "SPX"), at the option of the holder thereof, pursuant to the terms and conditions specified in paragraph 7 of the Securities and as set forth in the Company Notice, dated April 8, 2005, and the Indenture, dated as of May 9, 2001 (the "Indenture"), between the Company and JPMorgan Chase Bank, N.A. (as successor to The Chase Manhattan Bank), as Trustee (the "Depositary").

By Facsimile Transmission Certified:   If by Overnight Courier or Hand:   If by Registered or Certified Mail:
JP Morgan Chase Bank, N.A.
(214) 468-6494
(For Eligible Institutions Only)
Attention: Frank Ivins		   JP Morgan Chase Bank, N.A.
ITS Bond Events
2001 Bryan Street, 9th Floor
Dallas, TX 75201		   JP Morgan Chase Bank, N.A.
ITS Bond Events
PO Box 2320
Dallas, TX 75221

        The instructions accompanying this Purchase Notice should be read carefully before this Purchase Notice is completed.

        This Purchase Notice can be used only if:

        Any beneficial owner whose Securities are registered in the name of a broker, dealer, commercial bank, trust company or other nominee and who wishes to surrender such Securities should contact such registered holder of the Securities promptly and instruct such registered holder to surrender on behalf of the beneficial owner.

        Delivery of this Purchase Notice and all other required documents to an address other than as set forth above does not constitute valid delivery to the Depositary. Delivery of documents to DTC or the Company does not constitute delivery to the Depositary. The method of delivery of all documents, including certificates representing Securities, is at the risk of the Holder. If delivery is by mail, registered mail with return receipt requested, properly insured, is recommended. You must sign this Purchase Notice in the appropriate space provided therefore, with signature guarantee if required, and complete the Form W-9 set forth below. See instructions 1, 2 and 12.

2

Ladies and Gentlemen:

        By execution of this Purchase Notice, each signatory hereof (the "undersigned") represents that the undersigned has received the Company Notice, dated April 8, 2005 (the "Company Notice"), of SPX Corporation, a Delaware corporation (the "Company" or "SPX"), which provides the notice to the holders (the "Holders") required pursuant to the Indenture, dated as of May 9, 2001 (the "Indenture"), between the Company and JPMorgan Chase Bank, N.A. (as successor to The Chase Manhattan Bank), a national banking association organized and existing under the laws of the United States of America as depositary (the "Depositary"). This Purchase Notice relates to the Company's Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior) (the "Securities"), and the Holder's right to surrender the Securities for purchase by the Company for $645.97 per $1,000 principal amount at maturity of the Securities (the "Purchase Price"), subject to the terms and conditions of the Indenture, paragraph 7 of the Securities and the Company Notice. Upon the terms and subject to the conditions set forth herein and the Indenture, and effective upon the acceptance for payment thereof, the undersigned hereby irrevocably sells, assigns and transfers all right and title to the Company in and to the Securities surrendered hereby.

        The undersigned hereby irrevocably constitutes and appoints the Depositary the true and lawful agent and attorney-in-fact of the undersigned (with full knowledge that the Depositary also acts as the agent of the Company) with respect to such Securities, with full power of substitution (such power-of-attorney being deemed to be an irrevocable power coupled with an interest) to (1) present such Securities and all evidences of transfer and authenticity to, or transfer ownership of, such Securities on the account books maintained by the Depository Trust Company ("DTC") to, or upon the order of, the Company, (2) present such Securities for transfer and cancellation on the books of the relevant security registrar, and (3) receive all benefits and otherwise exercise all rights of beneficial ownership of such Securities, all in accordance with the terms of and conditions to the Company Notice and the Indenture.

        The undersigned hereby represents and warrants that:

        The undersigned understands that surrender of the Securities is not made in acceptable form until receipt by the Depositary of this Purchase Notice, duly completed and signed, together with all accompanying evidence of authority in form satisfactory to the Company in its sole discretion (which may delegate power in whole or in part to the Depositary). All questions as to form of documents, eligibility, validity (including time of receipt) and acceptance for payment of any surrender of Securities for purchase hereunder will be determined by the Company in its sole discretion (which may delegate power in whole or in part to the Depositary) and such determination shall be final and binding on all parties.

3

        The undersigned understands that all Securities properly surrendered for purchase and not withdrawn prior to 5:00 p.m., New York City time, on Monday, May 9, 2005 (the "Purchase Date") will be purchased at the Purchase Price, in cash, upon the terms and conditions specified in the Indenture, paragraph 7 of the Securities and as set forth in the Company Notice. The undersigned understands that acceptance of the Securities by the Company for payment will constitute a binding agreement between the undersigned and the Company upon the terms and subject to the conditions of the Indenture, the Company Notice and this Purchase Notice.

        The check for the aggregate Purchase Price for such of the Securities surrendered hereby as are purchased will be issued to the order of the undersigned and mailed to the address indicated in the box entitled "Description of Securities Being Surrendered for Purchase," unless otherwise indicated in the boxes entitled "Special Issuance Instructions" or "Special Delivery Instructions" herein. In the event that the boxes entitled "Special Issuance Instructions" and/or "Special Delivery Instructions" are completed, the check will be issued in the name of, and the payment of the aggregate Purchase Price will be mailed to, the address so indicated.

        All authority conferred or agreed to be conferred in this Purchase Notice shall not be affected by and shall survive the death or incapacity of the undersigned, and any obligations of the undersigned under this Purchase Notice shall be binding upon the heirs, personal representatives, successors and assigns of the undersigned.

NOTE: SIGNATURES MUST BE PROVIDED

PLEASE READ THE ACCOMPANYING INSTRUCTIONS CAREFULLY

4
DESCRIPTION OF SECURITIES BEING SURRENDERED FOR PURCHASE

Name(s) and Address(es) of Registered Holder(s)
(Please fill in exactly as name(s) appear(s) on Securities)(1)

   Securities Surrendered for Purchase
(Attach additional signed list, if necessary)

 
    
   Security
Certificate
Number(s)(2)

   Principal Amount
Represented by
Securities

   Principal Amount
Surrendered for
Purchase(2)(3)

            
            
            
        Total Amount
Surrendered for
Purchase		        
(1)   Must correspond exactly to the name(s) that appear(s) on the certificate(s) for the Securities and the Depositary's record of registered holders or, if surrendered by a DTC participant, exactly as such participant's name(s) and address(es) appear(s) on the security position listing of DTC.
(2)   Need not be completed if Securities are being surrendered for purchase by book-entry transfer.
(3)   If you desire to surrender for purchase less than the entire principal amount evidenced by the Securities listed above, please indicate in this column the portion of the principal amount of such Securities that you wish to surrender for purchase, otherwise, the entire principal amount evidenced by such Securities will be deemed to have been surrendered for purchase.

METHOD OF DELIVERY

o
CHECK HERE IF SECURITIES ARE BEING PHYSICALLY DELIVERED HEREWITH.

o
CHECK HERE IF SECURITIES ARE BEING DELIVERED BY BOOK-ENTRY TRANSFER MADE TO THE ACCOUNT MAINTAINED BY THE DEPOSITARY WITH DTC, AND COMPLETE THE FOLLOWING:

Name of Surrendering Institution:    
DTC Account Number:    
Contact Person:    
Address:    
Telephone (with international dialing code):    
Facsimile (with international dialing code):    
Date Surrendered:    
Transaction Code Number:    

5

Name:       
(Please Print)

Address:
 
    

 
 
    
(Include Zip Code)

 
 
    
(Taxpayer Identification Number or
Social Security Number)
    
(DTC Account Number)

    
(Account Party)
Name:       
(Please Print)

Address:
 
    

 
 
    

 
 
    
(Include Zip Code)

NOTE: SIGNATURES MUST BE PROVIDED ON THE FOLLOWING PAGE.
PLEASE READ THE ACCOMPANYING INSTRUCTIONS CAREFULLY.

6

    

    
Signature(s) of Holder(s)
Date:    
 , 2005    
Name(s):       

    
(Please Print)
Capacity:       
Area Code(s) and Telephone Number(s):       
Tax Id./S.S. Number(s):       
(Taxpayer Identification Number(s) or Social Security Number(s))
Address(es):       
(Include Zip Code)
Authorized Signature:       
Name:       
Title:       
Name of Eligible Institution:       
Address:       
Area Code and Telephone Number:       
Date:    
 , 2005    

7

INSTRUCTIONS

Forming Part of the Terms and Conditions of this Purchase Notice

        1.    Delivery of Purchase Notice and Securities.    This Purchase Notice can be used only if Securities are to be delivered with it to the Depositary or a surrender of Securities is being made concurrently by book-entry transfer to the Depositary's account at DTC. Holders that surrender through DTC need not submit a physical Purchase Notice to the Depositary if such Holders comply with the transmittal procedures of DTC. Securities or confirmation of the delivery of Securities by book-entry transfer to the Depositary through DTC, together with a properly completed and duly executed Purchase Notice or agent's message and any other required documents, should be delivered to the Depositary at the appropriate address set forth on the first page of this Purchase Notice and must be received by the Depositary prior to 5:00 p.m., New York City time, on Monday, May 9, 2005. The term "agent's message" means a message, transmitted to DTC and received by the Depositary and forming a part of a book-entry transfer, that states that DTC has received an express acknowledgement that the undersigned agrees to be bound by this Purchase Notice and that the Company may enforce this Purchase Notice against the undersigned. Delivery of documents to DTC or the Company does not constitute delivery to the Depositary.

        The method of delivery of all documents, including Securities, this Purchase Notice and any other required documents, is at the election and risk of the surrendering Holder(s). If delivery is by mail, registered mail with return receipt requested, properly insured, is recommended.

        Each surrendering Holder, by execution of this Purchase Notice, waives any right to receive any notice of the acceptance of his or her surrender.

        2.    Guarantee of Signatures.    No signature guarantee is required if either:

        In all other cases an Eligible Institution must guarantee the signatures on this Purchase Notice. See Instruction 5.

        3.    Inadequate Space.    If the space provided in the box captioned "Description of Securities Being Surrendered for Purchase" is inadequate, the Security certificate numbers, the principal amount represented by the Securities and the principal amount surrendered should be listed on a separate signed schedule and attached to this Purchase Notice.

        4.    Partial Surrenders and Unpurchased Securities.    (Not applicable to Holders who surrender by book-entry transfer.) If less than all of the principal amount evidenced by the Securities is to be surrendered for purchase, fill in the portion of the principal amount of such Securities which is to be surrendered for purchase in the column entitled "Principal Amount Surrendered for Purchase" in the box captioned "Description of Securities Being Surrendered for Purchase." In such case, a new certificate for the remainder of the Securities evidenced by the old certificate will be issued and sent to the registered Holder(s), unless otherwise specified in the box entitled "Special Issuance Instructions" and/or "Special Delivery Instructions" in this Purchase Notice, as promptly as practicable following the Purchase Date; provided, however, that each Security purchased and each new Security issued shall be in a principal amount at maturity of $1,000 or integral multiples thereof. The full principal amount of

8


Securities listed and delivered to the Depositary is deemed to have been surrendered unless otherwise indicated.

        5.    Signatures on Purchase Notice and Endorsements.    

        6.    Special Payment and Special Delivery Instructions.    The surrendering Holder(s) signing this Purchase Notice should indicate in the applicable box or boxes the name and address to which Securities for principal amounts not surrendered or checks for payment of the aggregate Purchase Price are to be issued or sent, if different from the name(s) and address(es) of such Holder(s). In the case of issuance in a different name, the taxpayer identification number or social security number of the person named must also be indicated. If no instructions are given, Securities not surrendered will be returned to the Holder(s). Any Holder(s) surrendering by book-entry transfer may request that Securities not surrendered be credited to such account at DTC as such Holder(s) may designate under the caption "Special Issuance Instructions." If no such instructions are given, any such Securities not surrendered will be returned by crediting the account at DTC designated above.

        7.    Irregularities.    The Company will determine, in its sole discretion, all questions as to the form of documents, eligibility, validity (including time of receipt) and acceptance for payment of any surrender of Securities and its determinations shall be final and binding on all parties. The Company reserves the absolute right to reject any or all surrenders it determines not to be in proper form or the acceptance for payment of or payment for which may, in the opinion of the Company's counsel, be unlawful. The Company also reserves the absolute right to waive any defect or irregularity in the surrender of any particular Security. No surrender of Securities will be deemed to have been properly made until all defects and irregularities have been cured or waived. Unless waived, any defects or irregularities in connection with surrenders must be cured within such time as the Company shall determine. The Company's interpretation of the terms of the Purchase Notice (including these instructions) will be final and binding on all parties. None of the Company, the Depositary or any other person is or will be obligated to give notice of any defects or irregularities in surrenders of Securities and none of them will incur any liability for failure to give such notice.

9


        8.    Mutilated, Lost, Stolen or Destroyed Certificates for Securities.    Any Holder(s) whose certificates for Securities have been mutilated, lost, stolen or destroyed should write to or telephone the Depositary at the address or telephone number set forth on the front cover page of this Purchase Notice.

        The Holder will then be instructed by the Depositary as to the steps that must be taken in order to replace the certificates. This Purchase Notice and related documents cannot be processed until the procedures for replacing mutilated, lost, stolen or destroyed certificates have been followed.

        9.    Questions and Requests for Assistance and Additional Copies.    Questions and requests for assistance may be directed to the Depositary and additional copies of the Company Notice and this Purchase Notice may also be obtained from the Depositary.

        10.    Withdrawal Rights.    You may withdraw previously surrendered Securities at any time until 5:00 p.m., New York City time, on May 9, 2005. Securities not accepted for payment after the expiration of forty business days from the commencement of the offer to purchase the Securities may be withdrawn. See Section 4 of the Company Notice for a more detailed description of withdrawal rights.

        11.    Transfer Taxes.    If payment of the Purchase Price is to be made to, or if Securities not surrendered or purchased are to be registered in the name of, any persons other than the registered Holder(s), or if surrendered Securities are registered in the name of any person other than the person(s) signing this Purchase Notice, the amount of any transfer taxes (whether imposed on the registered Holder(s) or such other person) payable on account of the transfer to such other person will be deducted from the Purchase Price unless satisfactory evidence of the payment of such taxes or an exemption therefrom is submitted.

        12.    Important Tax Information.    Under U.S. federal income tax law, a Holder that surrenders Securities is required to provide the Depositary with such Holder's current taxpayer identification number ("TIN") on a properly completed Form W-9, or, alternatively, to establish another basis for an exemption from backup withholding. If such Holder is an individual, the TIN is his or her Social Security number. If the Depositary is not provided with the correct TIN, the Holder may be subject to a $50 penalty imposed by the Internal Revenue Service. In addition, any payment made to such Holder with respect to Securities purchased pursuant to the Company Notice may be subject to 28% backup withholding.

        Certain Holders (including, among others, all corporations and certain foreign individuals) are not subject to these backup withholding and reporting requirements. In order for a foreign individual to qualify as an exempt recipient, that Holder must submit to the Depositary a properly completed Internal Revenue Service Form W-8 BEN (a "Form W-8 BEN"), signed under penalties of perjury, attesting to that individual's exempt status. A Form W-8 BEN can be obtained from the Depositary. See the enclosed Form W-9 for additional instructions.

        If backup withholding applies, the Depositary is required to withhold 28% of any payment made to the Holder or other payee. Backup withholding is not an additional tax. Rather, the federal income tax liability of persons subject to backup withholding will be reduced by the amount of tax withheld. If withholding results in an overpayment of taxes, a refund may be obtained from the Internal Revenue Service. The Depositary cannot refund amounts withheld by reason of backup withholding.

10



QuickLinks

PURCHASE NOTICE TO SURRENDER SPX CORPORATION LIQUID YIELD OPTION™ NOTES DUE FEBRUARY 6, 2021 (ZERO COUPON-SENIOR)

QuickLinks -- Click here to rapidly navigate through this document

Exhibit (a)(1)(C)


NOTICE OF WITHDRAWAL
OF SURRENDER OF
SPX CORPORATION'S LIQUID YIELD OPTION™ NOTES DUE May 9, 2021
(ZERO COUPON-SENIOR)

CUSIP Numbers: 784635 AF 1*

Pursuant to the Company Notice
dated April 8, 2005

*
No representation is made with respect to the accuracy of the CUSIP number as printed on the Securities or as contained herein.

THIS OFFER WILL EXPIRE AT 5:00 P.M., NEW YORK CITY TIME, ON MAY 9, 2005 (THE "PURCHASE DATE"). REGISTERED HOLDERS OF SECURITIES MUST SURRENDER THEIR SECURITIES ON OR PRIOR TO 5:00 P.M., NEW YORK CITY TIME, ON THE PURCHASE DATE IN ORDER TO RECEIVE THE PURCHASE PRICE. SECURITIES SURRENDERED FOR PURCHASE MAY BE WITHDRAWN IF THE REGISTERED HOLDER SUBMITS AND THE DEPOSITARY RECEIVES THIS COMPLETED AND SIGNED NOTICE OF WITHDRAWAL NO LATER THAN 5:00 P.M., NEW YORK CITY TIME, ON MAY 9, 2005. SECURITIES NOT ACCEPTED FOR PAYMENT AFTER THE EXPIRATION OF FORTY BUSINESS DAYS FROM THE COMMENCEMENT OF THE OFFER TO PURCHASE THE SECURITIES MAY BE WITHDRAWN. HOLDERS THAT SURRENDER THROUGH DTC NEED NOT SUBMIT A PHYSICAL PURCHASE NOTICE TO THE DEPOSITARY IF SUCH HOLDERS COMPLY WITH THE TRANSMITTAL PROCEDURES OF DTC.

The Depositary is:
JPMorgan Chase Bank, N.A.

JPMorgan Chase Bank, N.A.
ITS Bond Events 2001 Bryan Street, 9th Floor Dallas, TX 75201

        All capitalized terms used but not defined herein shall have the meanings ascribed to them in the Company Notice, dated April 8, 2005 and the accompanying Purchase Notice, of SPX Corporation, a Delaware corporation, (the "Company" or "SPX"), relating to the purchase by the Company, at the option of the holder thereof, of the Company's Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior) (the "Securities") for $645.97 per $1,000 principal amount at maturity of the Securities, subject to the terms and conditions of the Indenture and the Option.

        This Notice of Withdrawal is to be completed by registered holders of Securities desiring to withdraw the surrender of such Securities in the Option if (i) Securities have been previously surrendered to the Depositary, or (ii) delivery of such Securities has been previously made by book-entry transfer to the Depositary's account at the Depository Trust Company ("DTC") pursuant to the book-entry transfer procedures described under the caption "Procedures to be Followed by Holders Electing to Surrender Securities for Purchase" in the Company Notice.

Ladies and Gentlemen:

        The undersigned hereby withdraws the undersigned's surrender for purchase to the Company of the Securities described below, which Securities were previously surrendered for purchase pursuant to the Company Notice.

        The undersigned understands that the withdrawal of Securities previously surrendered in this Option, effected by this Notice of Withdrawal, may not be rescinded and that such Securities will no longer be deemed to be validly surrendered for purchase for purposes of the undersigned's Purchase Notice. Such withdrawn Securities may be resurrendered for purchase only by following the procedures for surrendering set forth in the Company Notice and in the accompanying Purchase Notice.

        All authority conferred or agreed to be conferred in this Notice of Withdrawal shall not be affected by and shall survive the death or incapacity of the undersigned, and any obligations of the undersigned under this Notice of Withdrawal shall be binding upon the heirs, personal and legal representatives, trustees in bankruptcy, successors and assigns of the undersigned.

* * *


DESCRIPTION OF SECURITIES BEING WITHDRAWN

Name(s) and Address(es) of Registered Holder(s)
(Please fill in exactly as name(s) appear(s) on Securities)(1)

   Securities Being Withdrawn
(Attach additional signed list, if necessary)

 
    
   Security
Certificate
Number(s)(2)

   Principal Amount
Represented by
Securities

   Principal Amount
Being
Withdrawn(2)(3)

            
            
            
            
        Total Amount
Being Withdrawn		        
(1)   Must correspond exactly to the name(s) that appear(s) on the certificate(s) for the Securities and the Depositary's record of registered holders or, if surrendered by a DTC participant, exactly as such participant's name(s) and address(es) appear(s) on the security position listing of DTC.
(2)   Need not be completed if Securities are being surrendered by book-entry transfer.
(3)   Unless otherwise specified, the entire aggregate principal amount evidenced by such Securities will be deemed to have been withdrawn.

METHOD OF DELIVERY

o
CHECK HERE IF SECURITIES WERE PHYSICALLY DELIVERED TO THE DEPOSITARY.

o
CHECK HERE IF SECURITIES WERE DELIVERED BY BOOK-ENTRY TRANSFER MADE TO THE ACCOUNT MAINTAINED BY THE DEPOSITARY WITH DTC AND COMPLETE THE FOLLOWING:

Name of Surrendering Institution:    
Address:    
Telephone:    
Facsimile:    
Contact Person:    
Date Surrendered:    
DTC Account Number:    
Transaction Code Number:    


    
(Signature(s) of Registered Holder(s) or Authorized Signatory)
Dated:    
 , 2005    
Name(s):       

    
(Please Print)
Capacity (full title):       
Address(es):       

    
(Include Zip Code)
Area Code(s) and Telephone Number(s):       
Authorized Signature:       
Name:       
Title:       
Name of Eligible Institution:       
Address:       

    
(Include Zip Code)
Area Code and Telephone Number:       
Dated:    
 , 2005    



QuickLinks

NOTICE OF WITHDRAWAL OF SURRENDER OF SPX CORPORATION'S LIQUID YIELD OPTION™ NOTES DUE May 9, 2021 (ZERO COUPON-SENIOR)

QuickLinks -- Click here to rapidly navigate through this document


Exhibit (a)(1)(D)

 

Form       W-9
(Rev. January 2005)
  
Department of the Treasury
Internal Revenue Service
Request for Taxpayer
Identification Number and Certification
  
Give form to the
requester. Do not
send to the IRS.

Print or type
See Specific Instructions on page 2.

  Name (as shown on your income tax return)                                   

 
  Business name, if different from above

 
  Check appropriate box:   o Individual/
    Sole proprietor		   o Corporation   o Partnership   o Other   > .............................   o Exempt from backup
    withholding

 
  Address (number, street, and apt. or suite no.)   Requester's name and address (optional)

 

 
 
 
 
  City, state, and ZIP code    

 
  List account number(s) here (optional)
    		    

  Part I Taxpayer Identification Number (TIN)

Enter your TIN in the appropriate box. The TIN provided must match the name given on Line 1 to avoid backup withholding. For individuals, this is your social security number (SSN). However, for a resident alien, sole proprietor, or disregarded entity, see the Part I instructions on page 3. For other entities, it is your employer identification number (EIN). If you do not have a number, see How to get a TIN on page 3.

Note. If the account is in more than one name, see the chart on page 4 for guidelines on whose number to enter.

Social security number
[  ][  ][  ]- [  ][  ]- [  ][  ][  ][  ]		 or       Employer identification number
[  ][  ]- [  ][  ][  ][  ][  ][  ]

  Part II Certification

Under penalties of perjury, I certify that:

1.
The number shown on this form is my correct taxpayer identification number (or I am waiting for a number to be issued to me), and
    

2.
I am not subject to backup withholding because: (a) I am exempt from backup withholding, or (b) I have not been notified by the Internal Revenue Service (IRS) that I am subject to backup withholding as a result of a failure to report all interest or dividends, or (c) the IRS has notified me that I am no longer subject to backup withholding, and
    

3.
I am a U.S. person (including a U.S. resident alien).

Certification instructions. You must cross out item 2 above if you have been notified by the IRS that you are currently subject to backup withholding because you have failed to report all interest and dividends on your tax return. For real estate transactions, item 2 does not apply. For mortgage interest paid, acquisition or abandonment of secured property, cancellation of debt, contributions to an individual retirement arrangement (IRA), and generally, payments other than interest and dividends, you are not required to sign the Certification, but you must provide your correct TIN. (See the instructions on page 4.)

Sign
Here		   Signature of
U.S. person		   Date >

Purpose of Form

A person who is required to file an information return with the IRS, must obtain your correct taxpayer identification number (TIN) to report, for example, income paid to you, real estate transactions, mortgage interest you paid, acquisition or abandonment of secured property, cancellation of debt, or contributions you made to an IRA.

U.S. person. Use Form W-9 only if you are a U.S. person (including a resident alien), to provide your correct TIN to the person requesting it (the requester) and, when applicable, to:

    1.     Certify that the TIN you are giving is correct (or you are waiting for a number to be issued),

    2.     Certify that you are not subject to backup withholding, or

    3.     Claim exemption from backup withholding if you are a U.S. exempt payee.

Note. If a requester gives you a form other than Form W-9 to request your TIN, you must use the requester's form if it is substantially similar to this Form W-9.

    For federal tax purposes you are considered a person if you are:

    Foreign person. If you are a foreign person, do not use Form W-9. Instead, use the appropriate Form W-8 (see Publication 515, Withholding of Tax on Nonresident Aliens and Foreign Entities).

Nonresident alien who becomes a resident alien.
Generally, only a nonresident alien individual may use the terms of a tax treaty to reduce or eliminate U.S. tax on certain types of income. However, most tax treaties contain a provision known as a "saving clause." Exceptions specified in the saving clause may permit an exemption from tax to continue for certain types of income even after the recipient has otherwise become a U.S. resident alien for tax purposes.

    If you are a U.S. resident alien who is relying on an exception contained in the saving clause of a tax treaty to claim an exemption from U.S. tax on certain types of income, you must attach a statement to Form W-9 that specifies the following five items:

    1.     The treaty country. Generally, this must be the same treaty under which you claimed exemption from tax as a nonresident alien.

    2.     The treaty article addressing the income.

    3.     The article number (or location) in the tax treaty that contains the saving clause and its exceptions.

    4.     The type and amount of income that qualifies for the exemption from tax.

    5.     Sufficient facts to justify the exemption from tax under the terms of the treaty article.

Example. Article 20 of the U.S.-China income tax treaty allows an exemption from tax for scholarship income received by a Chinese student temporarily present in the United States. Under U.S. law, this student will become a resident alien for tax purposes if his or her stay in the United States exceeds 5 calendar years. However, paragraph 2 of the first Protocol to the U.S.-China treaty (dated April 30, 1984) allows the provisions of Article 20 to continue to apply even after the Chinese student becomes a resident alien of the United States. A Chinese student who qualifies for this exception (under paragraph 2 of the first protocol) and is relying on this exception to claim an exemption from tax on his or her scholarship or fellowship income would attach to Form W-9 a statement that includes the information described above to support that exemption.

    If you are a nonresident alien or a foreign entity not subject to backup withholding, give the requester the appropriate completed Form W-8.

What is backup withholding? Persons making certain payments to you must under certain conditions withhold and pay to the IRS 28% of such payments (after December 31, 2002). This is called "backup withholding." Payments that may be subject to backup withholding include interest, dividends, broker and barter exchange transactions, rents, royalties, nonemployee pay, and certain payments from fishing boat operators. Real estate transactions are not subject to backup withholding.

    Cat. No. 10231X   Form W-9 (Rev. 1-2005)

Form W-9 (Rev. 1-2005)                                                                                                                           Page 2

    You will not be subject to backup withholding on payments you receive if you give the requester your correct TIN, make the proper certifications, and report all your taxable interest and dividends on your tax return.

Payments you receive will be subject to backup withholding if:

    1.     You do not furnish your TIN to the requester, or

    2.     You do not certify your TIN when required (see the Part II instructions on page 4 for details), or

    3.     The IRS tells the requester that you furnished an incorrect TIN, or

    4.     The IRS tells you that you are subject to backup withholding because you did not report all your interest and dividends on your tax return (for reportable interest and dividends only), or

    5.     You do not certify to the requester that you are not subject to backup withholding under 4 above (for reportable interest and dividend accounts opened after 1983 only).

    Certain payees and payments are exempt from backup withholding. See the instructions below and the separate Instructions for the Requester of Form W-9.

Penalties

Failure to furnish TIN. If you fail to furnish your correct TIN to a requester, you are subject to a penalty of $50 for each such failure unless your failure is due to reasonable cause and not to willful neglect.

Civil penalty for false information with respect to withholding. If you make a false statement with no reasonable basis that results in no backup withholding, you are subject to a $500 penalty.

Criminal penalty for falsifying information. Willfully falsifying certifications or affirmations may subject you to criminal penalties including fines and/or imprisonment.

Misuse of TINs. If the requester discloses or uses TINs in violation of federal law, the requester may be subject to civil and criminal penalties.

Specific Instructions

Name

If you are an individual, you must generally enter the name shown on your social security card. However, if you have changed your last name, for instance, due to marriage without informing the Social Security Administration of the name change, enter your first name, the last name shown on your social security card, and your new last name.

    If the account is in joint names, list first, and then circle, the name of the person or entity whose number you entered in Part I of the form.

Sole proprietor. Enter your individual name as shown on your social security card on the "Name" line. You may enter your business, trade, or "doing business as (DBA)" name on the "Business name" line.

Limited liability company (LLC). If you are a single-member LLC (including a foreign LLC with a domestic owner) that is disregarded as an entity separate from its owner under Treasury regulations section 301.7701-3, enter the owner's name on the "Name" line. Enter the LLC's name on the "Business name" line. Check the appropriate box for your filing status (sole proprietor, corporation, etc.), then check the box for "Other" and enter "LLC" in the space provided.

Other entities. Enter your business name as shown on required Federal tax documents on the "Name" line. This name should match the name shown on the charter or other legal document creating the entity. You may enter any business, trade, or DBA name on the "Business name" line.

Note. You are requested to check the appropriate box for your status (individual/sole proprietor, corporation, etc.).

Exempt From Backup Withholding

If you are exempt, enter your name as described above and check the appropriate box for your status, then check the "Exempt from backup withholding" box in the line following the business name, sign and date the form.

    Generally, individuals (including sole proprietors) are not exempt from backup withholding. Corporations are exempt from backup withholding for certain payments, such as interest and dividends.

Note. If you are exempt from backup withholding, you should still complete this form to avoid possible erroneous backup withholding.

Exempt payees. Backup withholding is not required on any payments made to the following payees:

    1.     An organization exempt from tax under section 501(a), any IRA, or a custodial account under section 403(b)(7) if the account satisfies the requirements of section 401(f)(2),

    2.     The United States or any of its agencies or instrumentalities,

    3.     A state, the District of Columbia, a possession of the United States, or any of their political subdivisions or instrumentalities,

    4.     A foreign government or any of its political subdivisions, agencies, or instrumentalities, or

    5.     An international organization or any of its agencies or instrumentalities.

    Other payees that may be exempt from backup withholding include:

    6.     A corporation,

    7.     A foreign central bank of issue,

    8.     A dealer in securities or commodities required to register in the United States, the District of Columbia, or a possession of the United States,

    9.     A futures commission merchant registered with the Commodity Futures Trading Commission,

    10.   A real estate investment trust,

    11.   An entity registered at all times during the tax year under the Investment Company Act of 1940,

    12.   A common trust fund operated by a bank under section 584(a),

    13.   A financial institution,

    14.   A middleman known in the investment community as a nominee or custodian, or

    15.   A trust exempt from tax under section 664 or described in section 4947.

    The chart below shows types of payments that may be exempt from backup withholding. The chart applies to the exempt recipients listed above, 1 through 15.

IF the payment is for…   THEN the payment is exempt for…
Interest and dividend payments   All exempt recipients except for 9
Broker transactions   Exempt recipients 1 through 13. Also, a person registered under the Investment Advisers Act of 1940 who regularly acts as a broker
Barter exchange transactions and patronage dividends   Exempt recipients 1 through 5
Payments over $600 required to be reported and direct sales over $5,0001   Generally, exempt recipients 1 through 72

1 See Form 1099-MISC, Miscellaneous Income, and its instructions.

2 However, the following payments made to a corporation (including gross proceeds paid to an attorney under section 6045(f), even if the attorney is a corporation) and reportable on Form 1099-MISC are not exempt from backup withholding: medical and health care payments, attorneys' fees; and payments for services paid by a Federal executive agency.

Part I. Taxpayer Identification Number (TIN)

Enter your TIN in the appropriate box. If you are a resident alien and you do not have and are not eligible to get an SSN, your TIN is your IRS individual taxpayer identification number (ITIN). Enter it in the social security number box. If you do not have an ITIN, see How to get a TIN below.

    If you are a sole proprietor and you have an EIN, you may enter either your SSN or EIN. However, the IRS prefers that you use your SSN.

    If you are a single-owner LLC that is disregarded as an entity separate from its owner (see Limited liability company (LLC) on page 2), enter your SSN (or EIN, if you have one). If the LLC is a corporation, partnership, etc., enter the entity's EIN.

Note. See the chart on page 4 for further clarification of name and TIN combinations.

How to get a TIN. If you do not have a TIN, apply for one immediately. To apply for an SSN, get Form SS-5, Application for a Social Security Card, from your local Social Security Administration office or get this form online at www.socialsecurity.gov/online/ss-5.pdf. You may also get this form by calling 1-800-772-1213. Use Form W-7, Application for IRS Individual Taxpayer Identification Number, to apply for an ITIN, or Form SS-4, Application for Employer Identification Number, to apply for an EIN. You can apply for an EIN online by accessing the IRS website at www.irs.gov/businesses/ and clicking on Employer ID Numbers under Related Topics. You can get Forms W-7 and SS-4 from the IRS by visiting www.irs.gov or by calling 1-800-TAX-FORM (1-800-829-3676).

    If you are asked to complete Form W-9 but do not have a TIN, write "Applied For" in the space for the TIN, sign and date the form, and give it to the requester. For interest and dividend payments, and certain payments made with respect to readily tradable instruments, generally you will have 60 days to get a TIN and give it to the requester before you are subject to backup withholding on payments. The 60-day rule does not apply to other types of payments. You will be subject to backup withholding on all such payments until you provide your TIN to the requester.

Note. Writing "Applied For" means that you have already applied for a TIN or that you intend to apply for one soon.

Caution: A disregarded domestic entity that has a foreign owner must use the appropriate Form W-8.

Part II. Certification

To establish to the withholding agent that you are a U.S. person, or resident alien, sign Form W-9. You may be requested to sign by the withholding agent even if items 1, 4, and 5 below indicate otherwise.

    For a joint account, only the person whose TIN is shown in Part I should sign (when required). Exempt recipients, see Exempt From Backup Withholding on page 2.

Signature requirements. Complete the certification as indicated in 1 through 5 below.

    1.     Interest, dividend, and barter exchange accounts opened before 1984 and broker accounts considered active during 1983. You must give your correct TIN, but you do not have to sign the certification.

    2.     Interest, dividend, broker, and barter exchange accounts opened after 1983 and broker accounts considered inactive during 1983. You must sign the certification or backup withholding will apply. If you are subject to backup withholding and you are merely providing your correct TIN to the requester, you must cross out item 2 in the certification before signing the form.

    3.     Real estate transactions. You must sign the certification. You may cross out item 2 of the certification.

    Cat. No. 10231X   Form W-9 (Rev. 1-2005)

Form W-9 (Rev. 1-2005)                                                                                                                           Page 3

    4.     Other payments. You must give your correct TIN, but you do not have to sign the certification unless you have been notified that you have previously given an incorrect TIN. "Other payments" include payments made in the course of the requester's trade or business for rents, royalties, goods (other than bills for merchandise), medical and health care services (including payments to corporations), payments to a nonemployee for services, payments to certain fishing boat crew members and fishermen, and gross proceeds paid to attorneys (including payments to corporations).

    5.     Mortgage interest paid by you, acquisition or abandonment of secured property, cancellation of debt, qualified tuition program payments (under section 529), IRA, Coverdell ESA, Archer MSA or HSA contributions or distributions, and pension distributions. You must give your correct TIN, but you do not have to sign the certification.

What Name and Number To Give the Requester

For this type of account:   Give name and SSN of:
1.   Individual   The individual
2.   Two or more individuals (joint account)   The actual owner of the account or, if combined funds, the first individual on the account 1

3.
 
Custodian account of a minor (Uniform Gift to Minors Act)
 
The minor 2

4.
 
a.
 
The usual revocable savings trust (grantor is also trustee)
 
The grantor-trustee 1
    b.   So-called trust account that is not a legal or valid trust under state law   The actual owner 1

5.
 
Sole proprietorship or single-owner LLC
 
The owner 3
For this type of account:   Give name and EIN of:
6.   Sole proprietorship or single-owner LLC   The owner 3

7.
 
A valid trust, estate, or pension trust
 
Legal entity 4

8.
 
Corporate or LLC electing corporate status on Form 8832
 
The corporation

9.
 
Association, club, religious, charitable, educational, or other tax-exempt organization
 
The organization

10.
 
Partnership or multi-member LLC
 
The partnership

11.
 
A broker or registered nominee
 
The broker or nominee

12.
 
Account with the Department of Agriculture in the name of a public entity (such as a state or local government, school district, or prison) that receives agricultural program payments
 
The public entity

1 List first and circle the name of the person whose number you furnish. If only one person on a joint account has an SSN, that person's number must be furnished.

2 Circle the minor's name and furnish the minor's SSN.

3 You must show your individual name and you may also enter your business or "DBA" name on the second name line. You may use either your SSN or EIN (if you have one). If you are a sole proprietor, IRS encourages you to use your SSN.

4 List first and circle the name of the legal trust, estate, or pension trust. (Do not furnish the TIN of the personal representative or trustee unless the legal entity itself is not designated in the account title.)

Note. If no name is circled when more than one name is listed, the number will be considered to be that of the first name listed.

Privacy Act Notice

Section 6109 of the Internal Revenue Code requires you to provide your correct TIN to persons who must file information returns with the IRS to report interest, dividends, and certain other income paid to you, mortgage interest you paid, the acquisition or abandonment of secured property, cancellation of debt, or contributions you made to an IRA, or Archer MSA or HSA. The IRS uses the numbers for identification purposes and to help verify the accuracy of your tax return. The IRS may also provide this information to the Department of Justice for civil and criminal litigation, and to cities, states, and the District of Columbia to carry out their tax laws. We may also disclose this information to other countries under a tax treaty, to federal and state agencies to enforce federal nontax criminal laws, or to federal law enforcement and intelligence agencies to combat terrorism.

    You must provide your TIN whether or not you are required to file a tax return. Payers must generally withhold 28% of taxable interest, dividend, and certain other payments to a payee who does not give a TIN to a payer. Certain penalties may also apply.



QuickLinks


QuickLinks -- Click here to rapidly navigate through this document

Exhibit (a)(5)(A)

Contact: Jeremy W. Smeltser (Investors)
               704-752-4478
               E-mail: investor@spx.com

               Tina L. Betlejewski (Media)
               704-752-4454
               E-mail: spx@spx.com


SPX ELECTS TO USE CASH FOR TENDERED LYONS DUE MAY 9, 2021

        CHARLOTTE, NC—April 8, 2005—SPX Corporation (NYSE: SPW) today announced that holders of its Liquid Yield Option™ Notes due May 9, 2021 (Zero Coupon-Senior) (the "LYONs") have the right to surrender their LYONs for purchase as of today. Each holder of the LYONs has the right to require SPX to purchase on May 9, 2005 all or any part of such holder's LYONs at a price equal to the issue price plus the accrued original issue discount. Under the terms of the LYONs, SPX had the option to pay for the LYONs with cash, SPX common stock, or a combination of cash and stock, and has elected to pay for the LYONs solely with cash. If all outstanding LYONs are surrendered for purchase, the aggregate cash purchase price will be approximately $17.9 million.

        In order to surrender LYONs for purchase, a purchase notice must be delivered to JPMorgan Chase Bank, the trustee for the LYONs, on or before 5:00 p.m. New York City time, on May 9, 2005. Holders of LYONs complying with the transmittal procedures of the Depository Trust Company need not submit a physical purchase notice to JPMorgan Chase Bank. Holders may withdraw any LYONs previously surrendered for purchase at any time prior to 5:00 p.m., New York City time, on May 9, 2005.

        SPX will file a Tender Offer Statement on Schedule TO with the Securities and Exchange Commission later today. SPX will make available to LYONs holders, through the Depository Trust Company, documents specifying the terms, conditions and procedures for surrendering and withdrawing LYONs for purchase. LYONs holders are encouraged to read these documents carefully before making any decision with respect to the surrender of LYONs, because these documents contain important information regarding the details of SPX's obligation to purchase the LYONs.

        The LYONs are convertible under certain circumstances into 8.8588 shares of SPX common stock per $1,000 principal amount at maturity of LYONs, subject to adjustment under certain circumstances (approximately 244,946 shares in the aggregate). The LYONs are not currently convertible.

        SPX Corporation is a leading global provider of thermal equipment and services, flow technology, test and measurement solutions and industrial products and services. For more information visit the company's web site at www.spx.com.

        Certain statements in this press release are forward-looking statements within the meaning of Section 21E of the Securities Exchange Act of 1934, as amended, and are subject to the safe harbor created thereby. Please refer to our public filings for discussion of certain important factors that relate to forward-looking statements contained in this press release. The words "believe," "expect," "anticipate," "estimate," "guidance," "target" and similar expressions identify forward-looking statements. Although the company believes that the expectations reflected in its forward-looking statements are reasonable, it can give no assurance that such expectations will prove to be correct. The safe harbor for forward-looking statements, however, does not apply to forward-looking statements made in connection with a tender offer, including LYONs holders' right to surrender LYONs for purchase.

        SPX Corporation shareholders are strongly advised to read the proxy statement relating to SPX Corporation's 2005 annual meeting of shareholders when it becomes available, as it will contain important information. Shareholders will be able to obtain this proxy statement, any amendments or


supplements to the proxy statement and any other documents filed by SPX Corporation with the Securities and Exchange Commission for free at the Internet website maintained by the Securities and Exchange Commission at www.sec.gov. In addition, SPX Corporation will mail the proxy statement to each shareholder of record on the record date to be established for the shareholders' meeting. Copies of the proxy statement and any amendments and supplements to the proxy statement will also be available for free at SPX Corporation's Internet website at www.spx.com or by writing to Investor Relations, SPX Corporation, 13515 Ballantyne Corporate Place, Charlotte, North Carolina 28277, telephone (704) 752-4400.

        SPX Corporation, its executive officers and directors may be deemed to be participants in the solicitation of proxies for SPX Corporation's 2005 annual meeting of shareholders. Information regarding these participants is contained in a filing under Rule 14a-12 filed by SPX Corporation with the Securities and Exchange Commission on March 16, 2005.

# # #



QuickLinks

SPX ELECTS TO USE CASH FOR TENDERED LYONS DUE MAY 9, 2021