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SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 11-K

Annual Report Pursuant to Section 15(d) of

The Securities Exchange Act of 1934

Commission file number  1-6948

A.                            Full title of the plan and the address of the plan, if different from that of the issuer named below: SPX Corporation Savings Plan

B.                            Name of the issuer of the securities held pursuant to the plan and the address of its principal executive office:

SPX Corporation

13515 Ballantyne Corporate Place

Charlotte, North Carolina 28277

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SPX Corporation Savings Plan

Financial Report

December 31, 2009

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Report of Independent Registered Public Accounting Firm

To the SPX Corporation Retirement and Welfare

Plan Administrative Committee

SPX Corporation Savings Plan

We have audited the accompanying statement of net assets available for benefits of the SPX Corporation Savings Plan as of December 31, 2009 and 2008 and the related statement of changes in net assets available for benefits for the year ended December 31, 2009.  These financial statements are the responsibility of the Plan’s management.  Our responsibility is to express an opinion on these financial statements based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States).  Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the financial statements are free of material misstatement.  The Plan is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. Our audit included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Plan’s internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation.  We believe that our audits provide a reasonable basis for our opinion.

In our opinion, the financial statements referred to above present fairly, in all material respects, the net assets of the SPX Corporation Savings Plan as of December 31, 2009 and 2008 and the changes in net assets for the year ended December 31, 2009, in conformity with accounting principles generally accepted in the United States of America.

Our audits were performed for the purpose of forming an opinion on the basic financial statements taken as a whole. The supplemental schedule of assets held at end of year as of December 31, 2009 is presented for the purpose of additional analysis and is not a required part of the basic financial statements but is supplementary information required by the Department of Labor’s Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. The supplemental schedule is the responsibility of the Plan’s management. The supplemental schedule has been subjected to the auditing procedures applied in the audits of the basic financial statements and, in our opinion, is fairly stated in all material respects in relation to the basic financial statements taken as a whole.

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SPX Corporation Savings Plan

Statement of Net Assets Available for Benefits

See Notes to Financial Statements

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SPX Corporation Savings Plan

Statement of Changes in Net Assets Available for Benefits

Year Ended December 31, 2009

See Notes to Financial Statements

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SPX Corporation Savings Plan

Notes to Financial Statements

December 31, 2009 and 2008

Note 1 - Description of the Plan

The following brief description of the SPX Corporation Savings Plan (the “Plan”) is provided for general information purposes only.  Participants should refer to the plan agreement for more complete information.

General - The Plan is a defined contribution plan and is subject to the provisions of the Employee Retirement Income Security Act of 1974 (“ERISA”).  The Plan benefits primarily employees of SPX Corporation (the “Employer” or the “Company”) who are covered by collective bargaining agreements and who have met eligibility requirements.

Contributions - Participants can elect to defer a portion of their compensation as a pretax contribution to the Plan, up to the maximum allowed under the Plan and the Internal Revenue Code.  Participants in the Plan are at all times 100 percent vested in their contributions and earnings thereon. Employer contributions are determined based on the participant’s business unit.

Participant Accounts - Each participant’s account is credited with the participant’s contributions, the Employer’s matching and supplemental contributions, if any, and an allocation of plan earnings.  Allocation of plan earnings to participant accounts is based on the participant’s proportionate share of funds in each of the investment accounts.  The benefit to which a participant is entitled is the benefit that can be provided from the participant’s account.

Participants elect to invest their account balance and contributions among various investment options provided by the SPX Corporation Retirement and Welfare Plan Administrative Committee (the “Committee”), including an option to invest in SPX Corporation common stock.

Vesting - Vesting in Employer contributions is dependent upon the participant’s business unit.  Generally, participants vest over a five to six year period.  Forfeitures reduce the Employer’s contributions in the year of forfeiture or future years.  Total forfeitures outstanding at December 31, 2009 and 2008 were $261,321 and $289,821, respectively.

Payment of Benefits - Participants in the Plan are able to receive benefits in a lump-sum, monthly or yearly installments, or through annuity payments in the event of death, disability, or termination of employment. Terminated participants with account balances over $1,000 can also elect to wait to receive benefits until retirement age. In addition, participants are also able to obtain their contributions and/or their pretax account balances if, subject to Employer approval, they are able to demonstrate financial hardship, as defined by the Plan.  All withdrawal payments are made by Fidelity Management Trust Company (the “Trustee”).

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Note 1 - Description of the Plan (Continued)

Participant Loans - A participant in the Plan can borrow from the Plan an amount not to exceed amounts as described in the Plan.  The term of the loan may not exceed five years unless the loan is used in the purchase of a primary residence, in which case the term may be for up to 15 years.  Loans bear rates of interest as outlined in the plan document.

Voting Rights - Each participant is entitled to exercise voting rights attributable to the shares allocated to his or her account. The Trustee is required to vote shares of common stock that have been allocated to participants but for which the Trustee received no voting instructions in the same manner and in the same proportion as the shares for which the Trustee received timely voting instructions.

Administration - The Company is the sponsor of the Plan. The Committee, as provided in the plan agreement, is the plan administrator and has responsibility for the administration of the Plan. The Trustee also functions as the investment manager.

Investment management fees and trustee fees are paid by the Plan in accordance with the plan agreement.

Termination - Although it has not expressed any intent to do so, the Company has the right to discontinue its contributions at any time and to terminate the Plan subject to the provisions of ERISA.  Upon termination, all participants become 100 percent vested in their account balances.

Note 2 - Summary of Significant Accounting Policies

The accompanying financial statements have been prepared on the accrual basis of accounting.

Investments - The Plan’s investments are stated at fair value.  The fair value of the Plan’s interest in the SPX Corporation Savings Trust (the “Master Trust”) is based on the beginning of the year value of the Plan’s interest in the Master Trust plus actual contributions and allocated income less actual distributions (see Note 3).  The Master Trust’s investments are stated at fair value.  Common collective trust funds that invest in fully benefit-responsive investment contracts (commonly known as stable value funds) within the Master Trust are adjusted to contract value in the financial statements.  Contract value represents contributions made under the contract, plus interest at the contract rate, less funds used to pay plan benefits. The fair value of the common collective trust fund is based on discounting the related cash flows of the underlying guaranteed investment contracts based on current yields of similar instruments with comparable durations. Quoted market prices are used to value all other investments in the Master Trust. The value of participant loans is the outstanding value, which approximates fair value.  Dividend income is accrued on the ex-dividend date.

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Note 2 - Summary of Significant Accounting Policies (Continued)

The methods described above may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values.  Furthermore, while the Plan believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different fair value measurement at the reporting date.

Benefit Payments - Benefits are recorded when paid.

Income Tax Status - The Plan constitutes a qualified plan under Sections 401(a) and 401(k) of the Internal Revenue Code (the “Code”), and the related trust is exempt from federal income tax under Section 501(a) of the Code. The Plan obtained a determination letter on December 4, 2003, in which the Internal Revenue Service stated that the Plan, as then designed, was in compliance with the applicable requirements of the Code.  Since the date of the determination letter, the Plan has been amended and restated. The plan administrator believes the Plan is currently designed and being operated in compliance with the applicable requirements of the Code.  Therefore, no provision for income taxes has been included in the Plan’s financial statements.

Use of Estimates - The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of additions and deductions during the reporting period.  Actual results could differ from those estimates.

Risks and Uncertainties - The Plan invests in various investment securities. Investment securities are exposed to various risks such as interest rate, market, and credit risks. Due to the level of risk associated with certain investment securities, it is at least reasonably possible that changes in the values of investment securities will occur in the near term and that such changes could materially affect participants’ account balances and the amounts reported in the statement of net assets available for benefits.

Note 3 - Master Trust Fund

The investments of certain defined contribution plans sponsored by SPX Corporation, including the Plan, are combined in the Master Trust. Under the terms of a trust agreement between the Trustee and the Company, the Trustee manages trust funds of the Master Trust on behalf of the Plan. These transactions qualify as party-in-interest transactions as defined under ERISA guidelines. The Plan’s assets in the Master Trust represented approximately 1.3 percent of the total assets in the Master Trust as of December 31, 2009 and 1.6 percent of the total assets in the Master Trust as of December 31, 2008.  Investment income and administrative expenses related to the Master Trust are allocated to the individual plans based upon average monthly balances invested by each plan.

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Note 3 - Master Trust Fund (Continued)

The total assets held in the Master Trust at December 31, 2009 and 2008 are as follows:

The investment gain for the Master Trust for the year ended December 31, 2009 is as follows:

Note 4 - Reconciliation of Financial Statements to Form 5500 (Annual Return/Report of Employee Benefit Plan)

The net assets on the financial statements differ from the net assets on the Form 5500 due to a common collective trust fund being recorded at contract value on the financial statements and at fair value on the Form 5500. The net assets on the financial statements were higher than Form 5500 at December 31, 2009 and 2008 by $27,736 and $110,248, respectively.  Additionally, the net increase in the net assets available for benefits on the Form 5500 for the year ended December 31, 2009 is higher by $82,512.

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Note 5 - Fair Value Measurements

Accounting standards require certain assets and liabilities be reported at fair value in the financial statements and provide a framework for establishing that fair value.  The framework for determining fair value is based on a hierarchy that prioritizes the inputs and valuation techniques used to measure fair value.

The Plan utilizes market data or assumptions that it believes market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs can be readily observable quoted prices in active markets for identical assets or liabilities (Level 1), significant other observable inputs (Level 2) or significant unobservable inputs (Level 3). The Plan’s assessment of the significance of particular inputs to these fair value measurements requires judgment and considers factors specific to each asset or liability.

During 2009, the Plan adopted, on a prospective basis, new accounting standards which require disclosure of fair value by major class of investments.

Disclosures concerning assets measured at fair value are as follows:

*                                         The common collective trust fund is a stable value fund which invests in investment contracts (wrap contracts) issued by insurance companies and other financial institutions, fixed income securities, and money market funds to provide daily liquidity. Wrap contracts are purchased in conjunction with an investment in fixed income securities, which may include, but are not limited to, U.S. Treasury and agency bonds, corporate bonds, mortgage-backed securities, commercial mortgage-backed securities, asset-backed securities and bond funds. The fair value of the common collective trust fund is based on discounting the related cash flows of the underlying guaranteed investment contracts based on current yields of similar instruments with comparable durations.

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Note 5 - Fair Value Measurements (Continued)

The table below sets forth a summary of changes in the fair value of the Plan’s Level 3 investment assets for the year ended December 31, 2009:

The Plan also holds other assets and liabilities not measured at fair value on a recurring basis, including accrued income, accrued liabilities and payables and unsettled trades.  The fair value of these assets and liabilities is equal to the carrying amounts in the accompanying financial statements due to the short maturity of such items.

Note 6 - Subsequent Event

Effective July 1, 2010, the SPX Corporation Savings Plan shall merge with and into the SPX Corporation Retirement Savings and Stock Ownership Plan.

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SPX Corporation Savings Plan

Schedule of Assets Held at End of Year

Form 5500, Schedule H, Item 4i

EIN 38-1016240, Plan 403

December 31, 2009

Note -               In compliance with the Department of Labor’s Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974, investments in Master Trust assets are omitted from this schedule.

Schedule 1

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SIGNATURES

The Plan. Pursuant to the requirements of the Securities Exchange Act of 1934, the trustees (or other persons who administer the employee benefit plan) have duly caused this annual report to be signed on its behalf by the undersigned hereunto duly authorized.

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Exhibit Index

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the registration statement (No. 333-106897) on Form S-8 of our report dated June 21, 2010 appearing in the Annual Report on Form 11-K of SPX Corporation Savings Plan as of December 31, 2009 and 2008 and for the year ended December 31, 2009.