Exhibit 10.15**SECOND AMENDMENT TO CREDIT AGREEMENT**     THIS SECOND AMENDMENT TO CREDIT AGREEMENT (this “***Amendment***”) is entered into as ofJanuary 11, 2006, but shall be effective for all purposes as of the Effective Date (defined below)among Powell Industries, Inc., a Delaware corporation (“***Parent***”), Switchgear & InstrumentationLtd., an entity organized under the laws of England and Wales (formerly known as Inhoco 3210Limited, “***Inhoco***”), Switchgear & Instrumentation Properties Limited, an entity organized under thelaws of England and Wales (“***SI Properties***” and together with Inhoco, “***UK Borrower***”), Bank ofAmerica, N.A., a national banking association, as Agent, Swing Line Lender and L/C Issuer under theCredit Agreement (in such capacity as administrative agent, together with its successors in suchcapacity, “***Agent***”), and each lender from time to time party to the Credit Agreement (collectively,“***Lenders***” and individually, a “***Lender***”). Capitalized terms used but not defined in this Amendmenthave the meaning given them in the Credit Agreement (defined below).**RECITALS**     A. Parent, Inhoco, and SI Properties, as borrowers (each a “***Borrower***” and collectively“***Borrowers***”), Agent and Lenders entered into that certain Credit Agreement dated as of June 29,2005 (as amended by the First Amendment to Credit Agreement dated November 7, 2005, and as amended,restated or supplemented the “***Credit Agreement***”).     B. Borrowers, Agent and Lenders have agreed to amend the Credit Agreement, subject to theterms and conditions of this Amendment.     NOW THEREFORE, for good and valuable consideration, the receipt and sufficiency of which areacknowledged, the undersigned hereby agree as follows:     1. Amendment to Credit Agreement. The Credit Agreement is amended as set forth belowas of the Effective Date:     (a) The definition of “Fiscal Year” in ***Section 1.01***of the Credit Agreement is deletedin its entirety and is replaced with the following:***Fiscal Year***means, as to Parent and its Subsidiaries, their fiscal yearending October 31, 2005, and thereafter each fiscal year ending September30.     (b) ***Sections 6.******01(a)******and (b)***of the Credit Agreement are deleted in their entirety andreplaced with the following:     “(a) as soon as available, but in any event within 120 days after the end ofeach fiscal year of Parent, a consolidated balance sheet of Parent and itsSubsidiaries as at the end of such fiscal year, and the related consolidatedstatements of income or operations, Shareholders’ Equity and cash flows for suchfiscal year, setting forth in each case in comparative form the figures for theprevious fiscal year, all in reasonable detail and prepared in accordance with
 

 
GAAP, audited and accompanied by a report and opinion of an independentcertified public accountant of nationally recognized standing reasonably acceptableto the Agent, which report and opinion shall be prepared in accordance withgenerally accepted auditing standards and shall not be subject to any “goingconcern” or like qualification or exception or any qualification or exception as tothe scope of such audit; and     (b) as soon as available, but in any event within 45 days after the end of eachfiscal quarter of each fiscal year of Parent, a consolidated balance sheet of Parentand its Subsidiaries as at the end of such fiscal quarter, and the relatedconsolidated statements of income or operations, Shareholders’ Equity and cash flowsfor such fiscal quarter and for the portion of Parent’s fiscal year then ended,setting forth in each case in comparative form the figures for the correspondingfiscal quarter of the previous fiscal year and the corresponding portion of theprevious fiscal year, all in reasonable detail and certified by a ResponsibleOfficer of Parent as fairly presenting the financial condition, results ofoperations, Shareholders’ Equity and cash flows of Parent and its Subsidiaries inaccordance with GAAP, subject only to normal year-end audit adjustments and theabsence of footnotes.”     (c) ***Section 6.******02(a)*** of the Credit Agreement is deleted in its entirety and replacedwith “[Intentionally Omitted].”     (d) ***Section 7.******11(f)*** of the Credit Agreement is deleted in its entirety and replacedwith the following:     “(f) Capital Expenditures. Make or become legally obligated tomake any expenditure in respect of the purchase or other acquisition of anyfixed or capital asset (excluding normal replacements and maintenance whichare properly charged to current operations), except for capital expendituresin the ordinary course of business not exceeding, in the aggregate forParent and it Subsidiaries, for the most recently completed four fiscalquarters ending on each quarterly date below, the amount set forth oppositesuch period:     Period Ending Maximum Capital Expenditures Quarter Ending July 31, 2005 $6,000,000 Quarter Ending October 31, 2005 $7,000,000 Quarter Ending January 31, 2006 $7,000,000”     2. Conditions. This Amendment shall be effective as of October 31, 2005 (the“***Effective Date***”) once each of the following have been delivered to Agent and Lenders:     (a) this Amendment executed by Borrowers, Agent and Lenders;     (b) Guarantors’ Consent and Agreement;
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     (c) Officer’s Certificate from Milburn E. Honeycutt, as Assistant Secretary ofBorrowers and each Guarantor certifying that the prior certificates delivered to Agent aretrue and correct as of the date hereof; and     (d) such other documents as Agent or Lenders may reasonably request.     3. Representations and Warranties. Each Borrower represents and warrants to Agent andLenders that (a) it possesses all requisite power and authority to execute, deliver and comply withthe terms of this Amendment, (b) this Amendment has been duly authorized and approved by allrequisite corporate action on the part of Borrower, (c) no other consent of any Person (other thanLenders) is required for this Amendment to be effective, (d) the execution and delivery of thisAmendment does not violate its organizational documents, (e) the representations and warranties ineach Loan Document to which it is a party are true and correct in all material respects on and asof the date of this Amendment as though made on the date of this Amendment (*except*to the extentthat such representations and warranties speak to a specific date), (f) it is in full compliancewith all covenants and agreements contained in each Loan Document to which it is a party, and (g)no Default or Event of Default has occurred and is continuing. The representations and warrantiesmade in this Amendment shall survive the execution and delivery of this Amendment. Noinvestigation by Agent or Lenders is required for Agent or Lenders to rely on the representationsand warranties in this Amendment.     4. Scope of Amendment; Reaffirmation; Release. All references to the Credit Agreementshall refer to the Credit Agreement as amended by this Amendment. Except as affected by thisAmendment, the Loan Documents are unchanged and continue in full force and effect. However, in theevent of any inconsistency between the terms of the Credit Agreement (as amended by this Amendment)and any other Loan Document, the terms of the Credit Agreement shall control and such otherdocument shall be deemed to be amended to conform to the terms of the Credit Agreement. Borrowershereby reaffirm their obligations under the Loan Documents to which each is a party and agree thatall Loan Documents to which they are a party remain in full force and effect and continue to belegal, valid, and binding obligations enforceable in accordance with their terms (as the same areaffected by this Amendment). Borrowers hereby release Agent and Lenders from any liability foractions or omissions in connection with the Credit Agreement and the other Loan Documents prior tothe date of this Amendment.     5. Miscellaneous.     (a) No Waiver of Defaults. This Amendment does not constitute (i) a waiver of,or a consent to, (A) any provision of the Credit Agreement or any other Loan Document notexpressly referred to in this Amendment, or (B) any present or future violation of, ordefault under, any provision of the Loan Documents, or (ii) a waiver of Agent’s or Lenders’right to insist upon future compliance with each term, covenant, condition and provision ofthe Loan Documents.     (b) Form. Each agreement, document, instrument or other writing to befurnished to Lenders under any provision of this Amendment must be in form and substancesatisfactory to Agent and its counsel.
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     (c) Headings. The headings and captions used in this Amendment are forconvenience only and will not be deemed to limit, amplify or modify the terms of thisAmendment, the Credit Agreement, or the other Loan Documents.     (d) Costs, Expenses and Attorneys’ Fees. Borrowers agree to pay or reimburseAgent on demand for all of their reasonable out-of-pocket costs and expenses incurred inconnection with the preparation, negotiation, and execution of this Amendment, including,without limitation, the reasonable fees and disbursements of Agent’s counsel.     (e) Successors and Assigns. This Amendment shall be binding upon and inure tothe benefit of each of the undersigned and their respective successors and permittedassigns.     (f) Multiple Counterparts. This Amendment may be executed in any number ofcounterparts with the same effect as if all signatories had signed the same document. Allcounterparts must be construed together to constitute one and the same instrument. ThisAmendment may be transmitted and signed by facsimile. The effectiveness of any suchdocuments and signatures shall, subject to applicable law, have the same force and effect asmanually-signed originals and shall be binding on Borrowers, Agent and Lenders. Agent mayalso require that any such documents and signatures be confirmed by a manually-signedoriginal; *provided that*the failure to request or deliver the same shall not limit theeffectiveness of any facsimile document or signature.     (g) Governing Law. This Amendment and the other Loan Documents must beconstrued, and their performance enforced, under Texas law.     (h) Entirety. **The Loan Documents (as amended hereby) Represent the FinalAgreement Between Borrowers, Agent and Lenders and May Not Be Contradicted by Evidence ofPrior, Contemporaneous, or Subsequent Oral Agreements by the Parties. There Are NoUnwritten Oral Agreements among the Parties.****[Signatures appear on the following pages.]**
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     The Amendment is executed as of the date set out in the preamble to this Amendment.        **BORROWERS:**         **POWELL INDUSTRIES, INC.**         By: /s/ Don R. Madison         Don R. MadisonVice President, Secretary and Treasurer       **SWITCHGEAR & INSTRUMENTATION LTD.**,formerly known as Inhoco 3210 Limited         By: /s/ Don R. Madison         Don R. MadisonDirector       **SWITCHGEAR & INSTRUMENTATION PROPERTIES LIMITED**         By: /s/ Don R. Madison         Don R. MadisonDirectorSignature Page to the Second Amendment to Credit Agreement
 

 
            **BANK OF AMERICA, N.A.**, as Agent             By: /s/ Daniel J. Lintner              Daniel J. Lintner      Senior Vice President           **BANK OF AMERICA, N.A.**, as a Lender, L/CIssuer and Swing Line Lender             By: /s/ Daniel J. Lintner              Daniel J. Lintner      Senior Vice PresidentSignature Page to the Second Amendment to Credit Agreement
 

 
**GUARANTORS’ CONSENT AND AGREEMENT TO SECOND AMENDMENT**     As an inducement to Agent and Lenders to execute, and in consideration of Agent’s and Lenders’execution of, this Amendment, the undersigned hereby consents to this Amendment and agrees thatthis Amendment shall in no way release, diminish, impair, reduce or otherwise adversely affect theobligations and liabilities of the undersigned under the Guaranty executed by each of theundersigned in connection with the Credit Agreement, or under any Loan Documents, agreements,documents or instruments executed by the undersigned to create liens, security interests or chargesto secure any of the Obligations (as defined in the Credit Agreement), all of which are in fullforce and effect. The undersigned further represents and warrants to Agent and Lenders that (a)the representations and warranties in each Loan Document to which it is a party are true andcorrect in all material respects on and as of the date of this Amendment as though made on the dateof this Amendment (except to the extent that such representations and warranties speak to aspecific date), (b) it is in full compliance with all covenants and agreements contained in eachLoan Document to which it is a party, and (c) no Default or Event of Default has occurred and iscontinuing. Guarantors hereby release Agent and Lenders from any liability for actions oromissions in connection with the Loan Documents prior to the date of this Amendment. ThisGuarantors’ Consent and Agreement shall be binding upon each of the undersigned, and its permittedassigns, and shall inure to the benefit of Agent, Lenders, and its successors and assigns.        **GUARANTORS:**           POWELL ELECTRICAL SYSTEMS, INC.,