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                                                                   EXHIBIT 10.10


                        FIRST AMENDMENT TO LOAN AGREEMENT

         This First Amendment to Loan Agreement (this "First Amendment") is made
and entered into as of the 30th day of September, 2002, by and between POWELL
INDUSTRIES, INC., a Nevada corporation ("Borrower"), and BANK OF AMERICA, N.A.,
a national banking association ("Lender").

                                   WITNESSETH:

         WHEREAS, pursuant to that certain Amended and Restated Loan Agreement
(the "Loan Agreement") dated October 25, 2001, Lender agreed to make certain
loans to Borrower upon the terms and conditions therein contained; and

         WHEREAS, Borrower and Lender desire to modify and amend certain terms
and provisions of the Loan Agreement.

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, Borrower and Lender agree as
follows:

         1. Amendments to Loan Agreement. Subject to and upon the full and
complete satisfaction of the terms and conditions of numerical Section 3 below,
the Loan Agreement is amended and modified as follows:

         1.1. The definition of the following term in Section 1.1 of the Loan
Agreement is deleted in its entirety and the following is substituted in place
thereof:

         "TERMINATION DATE" shall mean the earlier to occur of (a) February 28,
         2005, or (b) an Event of Default.

         2. Reaffirmation of Representations and Warranties. To induce the
Lender to enter into this First Amendment, Borrower hereby reaffirms, as of the
date hereof, its representations and warranties in their entirety contained in
the Loan Agreement and in all other Loan Documents executed by Borrower pursuant
thereto (except to the extent such representations and warranties relate solely
to an earlier date in which case they shall have been true and accurate in all
respects as of such earlier date) and additionally represents and warrants as
follows:

         2.1. The execution and delivery of this First Amendment and the
performance by Borrower of its obligations under this First Amendment and the
Loan Agreement as amended hereby are within Borrower's powers, have been duly
authorized by all necessary action, have received all necessary governmental and
other approvals (if any shall be required), and do not and will not contravene
or conflict with the governance documents of Borrower or any provision of law,
any presently existing requirement or restriction imposed by any judicial,
arbitral, regulatory or governmental instrumentality or constitute a default
under, or result in the creation or imposition of any lien other than a lien
permitted by the terms of the Loan Agreement upon any property or assets of


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Borrower or any Guarantor under, any agreement, instrument or indenture by which
Borrower or any Guarantor is bound;

         2.2. This First Amendment has been duly executed and delivered on
behalf of Borrower and this First Amendment and the Loan Agreement, as amended
hereby, are the legal, valid and binding obligations of Borrower, enforceable in
accordance with their terms subject as to enforcement only to bankruptcy,
insolvency, reorganization, moratorium or other similar laws and equitable
principles affecting the enforcement of creditors' rights generally; and

         2.3. No Default or Event of Default has occurred and is continuing
after giving effect to this First Amendment.

         3. Conditions. The effectiveness of this First Amendment is subject to
the following conditions, all in form and substance satisfactory to the Lender:

         3.1. The Lender shall have received and approved:

                  (a) First Amendment. A counterpart of this First Amendment
         executed by Borrower and Guarantors;

                  (b) Other Documents. Such other documents as the Lender may
         reasonably request (which shall include without limitation, partnership
         certificates, and other authorization documents required by Lender in
         connection with the foregoing); and

                  (c) Expenses. Reimbursement for all of Lender's fees and
         expenses (including attorneys' fees) incurred in connection with the
         preparation, negotiation, and execution of this First Amendment.

         3.2. All legal matters incident to the execution and delivery of this
First Amendment shall be satisfactory to the Lender.

         3.3. No Default or Event of Default shall be then continuing.

         4. Arbitration and Waiver of Jury Trial.

                  (a) THIS SECTION CONCERNS THE RESOLUTION OF ANY CONTROVERSIES
         OR CLAIMS BETWEEN THE BORROWER AND THE LENDER, WHETHER ARISING IN
         CONTRACT, TORT OR BY STATUTE, INCLUDING BUT NOT LIMITED TO
         CONTROVERSIES OR CLAIMS THAT ARISE OUT OF OR RELATE TO: (i) THIS FIRST
         AMENDMENT AND THE LOAN AGREEMENT (INCLUDING ANY RENEWALS, EXTENSIONS OR
         MODIFICATIONS); OR (II) ANY DOCUMENT RELATED TO THIS FIRST AMENDMENT
         AND THE LOAN AGREEMENT (COLLECTIVELY A "CLAIM").

                  (b) AT THE REQUEST OF THE BORROWER OR LENDER, ANY CLAIM SHALL
         BE RESOLVED BY BINDING ARBITRATION IN ACCORDANCE WITH THE FEDERAL
         ARBITRATION ACT (TITLE 9, U. S. CODE) (THE "ACT"). THE ACT WILL
         APPLY EVEN THOUGH THIS


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         AGREEMENT PROVIDES THAT IT IS GOVERNED BY THE LAW OF A SPECIFIED
         STATE.

                  (c) ARBITRATION PROCEEDINGS WILL BE DETERMINED IN ACCORDANCE
         WITH THE ACT, THE APPLICABLE RULES AND PROCEDURES FOR THE ARBITRATION
         OF DISPUTES OF JAMS OR ANY SUCCESSOR THEREOF ("JAMS"), AND THE TERMS OF
         THIS SECTION. IN THE EVENT OF ANY INCONSISTENCY, THE TERMS OF THIS
         PARAGRAPH SHALL CONTROL.

                  (d) THE ARBITRATION SHALL BE ADMINISTERED BY JAMS AND
         CONDUCTED IN ANY U. S. STATE WHERE REAL OR TANGIBLE PERSONAL PROPERTY
         COLLATERAL FOR THIS CREDIT IS LOCATED OR IF THERE IS NO SUCH
         COLLATERAL, IN TEXAS. ALL CLAIMS SHALL BE DETERMINED BY ONE ARBITRATOR;
         HOWEVER, IF CLAIMS EXCEED $5,000,000, UPON THE REQUEST OF ANY PARTY,
         THE CLAIMS SHALL BE DECIDED BY THREE ARBITRATORS. ALL ARBITRATION
         HEARINGS SHALL COMMENCE WITHIN 90 DAYS OF THE DEMAND FOR ARBITRATION
         AND CLOSE WITHIN 90 DAYS OF COMMENCEMENT AND THE AWARD OF THE
         ARBITRATOR(S) SHALL BE ISSUED WITHIN 30 DAYS OF THE CLOSE OF THE
         HEARING. HOWEVER, THE ARBITRATOR(S), UPON A SHOWING OF GOOD CAUSE, MAY
         EXTEND THE COMMENCEMENT OF THE HEARING FOR UP TO AN ADDITIONAL 60 DAYS.
         THE ARBITRATOR(S) SHALL PROVIDE A CONCISE WRITTEN STATEMENT OF REASONS
         FOR THE AWARD. THE ARBITRATION AWARD MAY BE SUBMITTED TO ANY COURT
         HAVING JURISDICTION TO BE CONFIRMED AND ENFORCED.

                  (e) THE ARBITRATOR(S) WILL HAVE THE AUTHORITY TO DECIDE
         WHETHER ANY CLAIM IS BARRED BY THE STATUTE OF LIMITATIONS AND, IF SO,
         TO DISMISS THE ARBITRATION ON THAT BASIS. FOR PURPOSES OF THE
         APPLICATION OF THE STATUTE OF LIMITATIONS, THE SERVICE ON JAMS UNDER
         APPLICABLE JAMS RULES OF A NOTICE OF CLAIM IS THE EQUIVALENT OF THE
         FILING OF A LAWSUIT. ANY DISPUTE CONCERNING THIS ARBITRATION PROVISION
         OR WHETHER A CLAIM IS ARBITRABLE SHALL BE DETERMINED BY THE
         ARBITRATOR(S). THE ARBITRATOR(S) SHALL HAVE THE POWER TO AWARD LEGAL
         FEES PURSUANT TO THE TERMS OF THIS FIRST AMENDMENT AND THE LOAN
         AGREEMENT.

                  (f) THIS SECTION DOES NOT LIMIT THE RIGHT OF THE BORROWER OR
         THE LENDER TO: (i) EXERCISE SELF-HELP REMEDIES, SUCH AS BUT NOT LIMITED
         TO, SETOFF; (ii) INITIATE JUDICIAL OR NONJUDICIAL FORECLOSURE AGAINST
         ANY REAL OR PERSONAL PROPERTY COLLATERAL; (iii) EXERCISE ANY JUDICIAL
         OR POWER OF SALE RIGHTS, OR (iv) ACT IN A COURT OF LAW TO OBTAIN AN
         INTERIM REMEDY, SUCH AS BUT NOT LIMITED TO, INJUNCTIVE RELIEF, WRIT OF
         POSSESSION OR


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         APPOINTMENT OF A RECEIVER, OR ADDITIONAL OR SUPPLEMENTARY REMEDIES.

                  (g) BY AGREEING TO BINDING ARBITRATION, THE PARTIES
         IRREVOCABLY AND VOLUNTARILY WAIVE ANY RIGHT THEY MAY HAVE TO A TRIAL BY
         JURY IN RESPECT OF ANY CLAIM. FURTHERMORE, WITHOUT INTENDING IN ANY WAY
         TO LIMIT THIS AGREEMENT TO ARBITRATE, TO THE EXTENT ANY CLAIM IS NOT
         ARBITRATED, THE PARTIES IRREVOCABLY AND VOLUNTARILY WAIVE ANY RIGHT
         THEY MAY HAVE TO A TRIAL BY JURY IN RESPECT OF SUCH CLAIM. THIS
         PROVISION IS A MATERIAL INDUCEMENT FOR THE PARTIES ENTERING INTO THIS
         FIRST AMENDMENT.

         5. NO CONTROL BY LENDER. BORROWER AGREES AND ACKNOWLEDGES THAT ALL OF
THE COVENANTS AND AGREEMENTS PROVIDED FOR AND MADE BY BORROWER IN THIS FIRST
AMENDMENT, THE LOAN AGREEMENT, AND IN THE OTHER LOAN DOCUMENTS ARE THE RESULT OF
EXTENSIVE AND ARMS-LENGTH NEGOTIATIONS BETWEEN BORROWER AND LENDER. LENDER'S
RIGHTS AND REMEDIES PROVIDED FOR IN THE LOAN AGREEMENT AND IN THE OTHER LOAN
DOCUMENTS ARE INTENDED TO PROVIDE LENDER WITH A RIGHT TO OVERSEE BORROWER'S
ACTIVITIES AS THEY RELATE TO THE LOAN TRANSACTIONS PROVIDED FOR IN THE LOAN
AGREEMENT, WHICH RIGHT IS BASED ON LENDER'S VESTED INTEREST IN BORROWER'S
ABILITY TO PAY THE NOTES AND PERFORM THE OTHER OBLIGATIONS. NONE OF THE
COVENANTS OR OTHER PROVISIONS CONTAINED IN THE LOAN AGREEMENT SHALL, OR SHALL BE
DEEMED TO, GIVE LENDER THE RIGHT OR POWER TO EXERCISE CONTROL OVER, OR OTHERWISE
IMPAIR, THE DAY-TO-DAY AFFAIRS, OPERATIONS, AND MANAGEMENT OF BORROWER; PROVIDED
THAT IF LENDER BECOMES THE OWNER OF ANY STOCK OF ANY ENTITY, WHICH ENTITY OWNS
AN INTEREST IN BORROWER, WHETHER THROUGH FORECLOSURE OR OTHERWISE, LENDER
THEREAFTER SHALL BE ENTITLED TO EXERCISE SUCH LEGAL RIGHTS AS IT MAY HAVE BY
BEING A SHAREHOLDER OF SUCH ENTITY.

6. Release. Borrower and Guarantors on their own behalf and on behalf of their
predecessors, successors and assigns (collectively, the "RELEASING PARTIES"),
hereby acknowledge and stipulate that as of the date of the execution of this
First Amendment, none of the Releasing Parties has any claims or causes of
action of any kind whatsoever against Lender or any of its officers, directors,
employees, agents, attorneys, or representatives, or against any of their
respective predecessors, successors, or assigns. Each of the Releasing Parties
hereby forever releases, remises, discharges and holds harmless Lender and all
of its officers, directors, employees, agents, attorneys, and representatives,
and all of their respective predecessors, successors, and assigns, from any and
all claims, causes of action, demands, and liabilities of any kind whatsoever,
whether direct or indirect, fixed or contingent, liquidated or non-liquidated,
disputed or undisputed, known or unknown, which any of the Releasing Parties has
or may acquire in the future relating in any way


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to any event, circumstance, action, or failure to act from the beginning of time
through the date of the execution of this First Amendment.

         7. Lien Continuation: Miscellaneous. The liens granted in the Loan
Documents are hereby ratified and confirmed as continuing to secure the payment
of the Notes. Nothing herein shall in any manner diminish, impair or extinguish
the Notes, as may be modified and increased under the Loan Agreement or the
liens securing the Notes. The liens granted in the Loan Documents are not
waived. The Security Agreement is specifically amended to secure Term Note B and
each other Note and all Swap Contracts. Borrower ratifies and acknowledges the
Loan Documents as valid, subsisting, and enforceable and agrees that the
indebtedness evidenced by the Notes is just, due, owing and unpaid, and is
subject to no offsets, deductions, credits, charges or claims of whatsoever kind
or character, and further agrees that all offsets, credits, charges and claims
of whatsoever kind or character are fully settled and satisfied.

         8. Defined Terms. Words and terms used herein which are defined in the
Loan Agreement are used herein as defined therein, except as specifically
modified by the terms of this First Amendment. Terms used in this First
Amendment which are not defined in the Loan Agreement are used therein as herein
defined.

         9. Miscellaneous.

         9.1. Preservation of the Loan Agreement. Except as specifically amended
and modified by the terms of this First Amendment, all of the terms, provisions,
covenants, warranties, and agreements contained in the Loan Agreement and in the
other Loan Documents shall remain in full force and effect (any irreconcilable
conflicts or inconsistencies between the terms of this First Amendment and the
Loan Agreement, or any other Loan Document, shall be governed and controlled by
this First Amendment).

         9.2. Counterparts. This First Amendment may be executed in two or more
counterparts, and it shall not be necessary that any one of the counterparts be
executed by all of the parties hereto. Each fully or partially executed
counterpart shall be deemed an original, but all such counterparts taken
together shall constitute but one and the same instrument.

         9.3. Joinder. Each of the Guarantors join in the execution of this
First Amendment to join in the release set forth in numerical section 6 above
and to evidence that their Guaranty remains in full force and effect and is not
limited or impaired as a result of the execution and delivery of this First
Amendment by Borrower.

         9.4. NO ORAL AGREEMENTS. THIS WRITTEN AGREEMENT AND THE OTHER WRITTEN
LOAN DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES AND MAY NOT BE
CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL
AGREEMENTS OF THE PARTIES. THERE ARE NOT UNWRITTEN ORAL AGREEMENTS BETWEEN THE
PARTIES.

         9.5. ACKNOWLEDGMENT. BORROWER HAS BEEN ADVISED BY LENDER TO SEEK THE
ADVICE OF AN ATTORNEY AND AN ACCOUNTANT IN CONNECTION WITH THE COMMERCIAL LOANS
EVIDENCED BY THE NOTES;


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AND BORROWER HAS HAD THE OPPORTUNITY TO SEEK THE ADVICE OF AN ATTORNEY AND
ACCOUNTANT OF BORROWER'S CHOICE IN CONNECTION WITH THE COMMERCIAL LOANS
EVIDENCED BY THE NOTES.

         IN WITNESS WHEREOF, the parties have executed this First Amendment as
of the date first above written.

                                     POWELL INDUSTRIES, INC.


                                     By: /s/ DON R. MADISON
                                         ---------------------------------
                                         Don R. Madison
                                         Vice President
                                         Chief Financial Officer

                                                                   BORROWER

                                     BANK OF AMERICA, N.A.


                                     By: /s/ DANIEL J. LINTNER
                                         ---------------------------------
                                     Name: Daniel J. Litner
                                           -------------------------------
                                     Title: Vice President
                                            ------------------------------


                                                                   LENDER




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