Exhibit 5.1

           [FRIED, FRANK, HARRIS, SHRIVER & JACOBSON LETTERHEAD]



                                                                 212-859-8272
April 4, 2002                                             (FAX: 212-859-8589)
SPX Corporation
2300 One Wachovia Center
Charlotte, North Carolina  28202-6039

Ladies and Gentlemen:

          We are acting as counsel to SPX Corporation, a Delaware
corporation (the "Company"), in connection with the Registration Statement
on Form S-3, as amended (the "Registration Statement"), under the
Securities Act of 1933, as amended (the "Securities Act"), with respect to
the contemplated issuance by the Company from time to time of up to U.S.
$1,000,000,000 aggregate public offering price or the equivalent thereof in
one or more foreign currencies, currency units or composite currencies of
(i) shares of the Company's common stock, par value $10.00 per share (the
"Common Stock"); (ii) one or more series of senior or subordinated debt
securities of the Company (the "Debt Securities"), which may be issued
pursuant to a senior debt indenture (the "Senior Indenture") or a
subordinated debt indenture (the "Subordinated Indenture," and, together
with the Senior Indenture, each an "Indenture" and collectively, the
"Indentures") to be entered into between the Company and The Chase
Manhattan Bank, as trustee (in such capacity, the "Trustee"); (iii) shares
of the Company's Preferred Stock, no par value, (the "Preferred Stock); and
(iv) warrants to purchase Common Stock (the "Warrants"); stock purchase
contracts and stock purchase units (the "Stock Purchase Contracts" and
"Stock Purchase Units", respectively). All capitalized terms used herein
that are defined in the Registration Statement have the meanings assigned
to such terms therein, unless otherwise defined herein. With your
permission, all assumptions and statements of reliance herein have been
made without any independent investigation or verification on our part
except to the extent otherwise expressly stated, and we express no opinion
with respect to the subject matter or accuracy of such assumptions or items
relied upon.

          In connection with this opinion, we have (i) investigated such
questions of law, (ii) examined originals or certified, conformed or
reproduction copies of such agreements, instruments, documents and records
of the Company, such certificates of public officials and such other
documents, and (iii) received such information from officers and
representatives of the Company as we have deemed necessary or appropriate
for the purposes of this opinion. We have examined, among other documents,
the Registration Statement and the Indentures.

          In all such examinations, we have assumed the legal capacity of
all natural persons, the genuineness of all signatures, the authenticity of
original and certified documents and the conformity to original or
certified documents of all copies submitted to us as conformed or
reproduction copies. As to various questions of fact relevant to the
opinions expressed herein, we have relied upon, and assume the accuracy of,
certificates and oral or written statements and other information of or
from representatives of the Company and others and assume compliance on the
part of all parties to the Indentures with their covenants and agreements
contained therein.

          To the extent it may be relevant to the opinions expressed below,
we have assumed that (i) the Company will have sufficient authorized but
unissued shares of Common Stock on the date of any issuance of Common Stock
or warrants registered pursuant to the Registration Statement, (ii) the
Company will have sufficient authorized but unissued shares of Preferred
Stock on the date of any issuance of Preferred Stock registered pursuant to
the Registration Statement and (iii) the Trustee will have the power and
authority to enter into and perform the Indentures and to consummate the
transactions contemplated thereby, that the Indentures will be duly
authorized, executed and delivered by, and will constitute the legal, valid
and binding obligations of, the Trustee, enforceable against the Trustee in
accordance with their terms, and that the Trustee will comply with all of
its obligations under the Indentures and all laws applicable thereto.

          Based upon the foregoing and subject to the limitations,
qualifications and assumptions set forth herein, we are of the opinion
that:

          1. When (i) the Registration Statement has become effective under
the Securities Act, (ii) the terms of the issuance and sale by the Company
of the shares of Common Stock registered pursuant to the Registration
Statement have been duly approved by the Board of Directors of the Company
in conformity with the Company's Certificate of Incorporation (the
"Certificate of Incorporation"), and (iii) such shares are issued and
delivered against payment therefor for an amount in excess of the par value
thereof and in accordance with the terms of the agreement under which they
are sold, such shares of Common Stock to be sold by the Company will be
validly issued, fully paid and non-assessable.

          2. When (i) the Registration Statement has become effective under
the Securities Act, (ii) the applicable Indenture and any relevant
supplemental indenture is duly executed and delivered by the Company, (iii)
the terms of the Debt Securities and their issue and sale have been duly
established in conformity with the applicable Indenture, do not violate any
applicable law or agreement or instrument then binding on the Company and
comply with any requirement or restriction imposed by any court or
governmental body having jurisdiction over the Company, and (iv) the Debt
Securities have been duly executed and authenticated in accordance with the
terms of the applicable Indenture and issued and sold as contemplated in
the Registration Statement, the Debt Securities will constitute valid and
binding obligations of the Company, enforceable against the Company in
accordance with the terms of the Debt Securities.

          3. When (i) the Registration Statement has become effective under
the Securities Act, (ii) the Board of Directors of the Company has fixed
the designations, relative rights, preferences and limitations of any
series of Preferred Stock and filed with the Office of the Secretary of
State of the State of Delaware, Division of Corporations, a Certificate of
Designations or an amendment to the Company's Certificate of Incorporation
setting forth the powers, designations, preferences and relative,
participating, optional or other rights, if any, or the qualifications,
limitations or restrictions thereof, if any, with respect to such series of
Preferred Stock, all in accordance with Section 151 of the General
Corporation Law of the State of Delaware and in conformity with the
Certificate of Incorporation, (iii) the Board of Directors of the Company
has approved the specific terms of the issuance and all necessary corporate
action on the part of the Company has been taken to authorize the issuance
and sale of such series of Preferred Stock, and (iv) when such shares of
Preferred Stock are issued and delivered against payment therefor, such
shares will be validly issued, fully paid and non-assessable.

          4. When (i) the Registration Statement has become effective under
the Securities Act, (ii) the issuance, execution and delivery by the
Company of any of the Warrants has been duly authorized by all necessary
corporate action of the Company, (iii) the warrant agreement relating
thereto has been executed and delivered by the respective parties thereto
and such Warrants have been duly executed and delivered by the Company,
countersigned by the warrant agent relating thereto, (iv) the terms of the
Warrants and their issue and sale have been duly established in conformity
with the applicable warrant agreements, do not violate any applicable law
or agreement or instrument then binding on the Company and comply with any
requirement or restriction imposed by any court or governmental body having
jurisdiction over the Company, and (v) such warrants are issued and
delivered against payment in accordance with the warrant agreement relating
thereto, assuming that the terms of such Warrants are in compliance with
then applicable law, such Warrants will be validly issued and enforceable
against the Company in accordance with their terms.

          5. When (i) the Registration Statement has become effective under
the Securities Act, (ii) the Stock Purchase Contracts and Stock Purchase
Units have been authorized, executed, and delivered by the Company, and if
in an underwritten offering, in accordance with the terms and conditions of
the applicable underwriting agreement, and in a manner contemplated by the
Registration Statement, and (iii) the terms of the Stock Purchase Contracts
and Stock Purchase Units and their issue and sale have been duly
established in conformity with the applicable stock purchase contract
agreements and stock purchase unit agreements, do not violate any
applicable law or agreement or instrument then binding on the Company and
comply with any requirement or restriction imposed by any court or
governmental body having jurisdiction over the Company, the Stock Purchase
Contracts and Stock Purchase Units will constitute valid and binding
obligations of the Company, enforceable in accordance with their terms.

          We express no opinion as to the enforceability of any provision
of the Indentures, warrant agreements, stock purchase contract agreements
or stock purchase unit agreements (i) providing for indemnification,
exculpation or contribution, (ii) specifying that provisions thereof may be
waived only in writing, to the extent that an oral agreement or an implied
agreement by trade practice or course of conduct has been created that
modifies any provision of the Indentures , warrant agreements, stock
purchase contract agreements or stock purchase unit agreements, (iii) as to
the legality, validity, binding effect or enforceability of any provision
of the Debt Securities, Indentures, Warrants, warrant agreements, Stock
Purchase Contracts, stock purchase contract agreements, Stock Purchase
Units or stock purchase unit agreements providing for payments thereunder
in a currency other than currency of the United States of America to the
extent that a court of competent jurisdiction, under applicable law, will
convert any judgment rendered in such other currency into currency of the
United States of America or to the extent that payment in a currency other
than currency of the United States of America is contrary to applicable
law, (iv) which waive or violate any usury law, (v) related to forum
selection, submission to jurisdiction or to choice of governing law, to the
extent that the validity, binding effect or enforceability of any such
provision is to be determined by any court other than a court of the State
of New York or a federal district court sitting in the State of New York
and applying the law of the State of New York, or (vi) purporting to give
any person or entity the power to accelerate obligations without any notice
to the obligor.

          The opinions set forth above are subject to (i) applicable
bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance,
fraudulent transfer, fraudulent obligation or preferential transfer law and
other similar laws affecting creditors' rights and remedies generally, and
(ii) general principles of equity including, without limitation, standards
of materiality, good faith, fair dealing and reasonableness, equitable
defenses and limits as to the availability of equitable remedies, whether
such principles are considered in a proceeding at law or in equity.

          The opinions expressed herein are limited to the federal laws of
the United States of America, the laws of the State of New York and, to the
extent relevant to the opinions expressed herein, the General Corporation
Law of the State of Delaware (the "DGCL") and applicable provisions of the
Delaware Constitution, in each case as currently in effect, and reported
judicial decisions interpreting the DGCL and such provisions of the
Delaware Constitution. The opinion expressed herein is given as of the date
hereof, and we undertake no obligation to supplement this letter if any
applicable laws change after the date hereof or if we become aware of any
facts that might change the opinion expressed herein after the date hereof
or for any other reason.

          We hereby consent to the use of our name on the front cover of
the Registration Statement, the filing of this opinion as an exhibit to the
Registration Statement and to the references to this firm under the
captions "Legal Matters" in the prospectus contained in the Registration
Statement and "Legal Matters" in any prospectus supplement forming a part
of the Registration Statement. In giving these consents, we do not hereby
admit that we are in the category of persons whose consent is required
under Section 7 of the Securities Act.

                                    Very truly yours,

                                    FRIED, FRANK, HARRIS, SHRIVER & JACOBSON

                                    By: /s/ Stuart H. Gelfond