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                                                                   EXHIBIT: (C)



(Execution Version 8/21/01)

                      WAIVER - MINIMUM EXCESS AVAILABILITY
                             ULTRAK OPERATING, L.P.
                   FIRST AMENDED AND RESTATED CREDIT AGREEMENT

         THIS WAIVER (this "Waiver") is executed as of and effective as of July
20, 2001 (for the period of July 20-27, 2001), among ULTRAK OPERATING, L.P., a
Texas limited partnership ("Borrower"), ULTRAK, INC., a Delaware corporation
("Parent"), AMERICAN NATIONAL BANK AND TRUST COMPANY OF CHICAGO (as a "Lender"),
HARRIS TRUST AND SAVINGS BANK (as a "Lender"), and AMERICAN NATIONAL BANK AND
TRUST COMPANY OF CHICAGO (as "Administrative Agent" for present and future
Lenders).

                                    RECITALS

         Borrower, Parent, Administrative Agent and Lenders are parties to that
certain First Amended and Restated Credit Agreement (as previously, hereby or
hereafter renewed, extended, modified, supplemented, amended and restated, the
"Credit Agreement") dated as of May 17, 2000, providing for, among other things,
a secured revolving credit facility. The parties to this Waiver have agreed to
supplement the Credit Agreement as set forth herein.

                                   AGREEMENTS

         NOW THEREFORE, in consideration of the premises, and for other good,
fair and valuable consideration, the receipt, adequacy and reasonable
equivalency of which are hereby acknowledged, the parties hereto agree as
follows:

1. Defined Terms; References. Unless otherwise stated in this Waiver, terms
defined in the Credit Agreement have the same meanings when used in this Waiver.
This Waiver is a "Credit Document" referred to in the Credit Agreement, and the
provisions relating to Credit Documents in the Credit Agreement are incorporated
by reference, the same as if set forth verbatim in this Waiver. Each Subsidiary
signing the Subsidiary Joinder at the end of this Waiver is herein called a
"Ratifying Subsidiary".

2.       Waivers.

         (a) Administrative Agent and Lenders hereby grant a temporary,
         revocable waiver of the Event of Default existing under Section 10.5 of
         the Credit Agreement during the period July 20-27, 2001 as a result of
         the fact that the Excess Availability was less than Two Million Dollars
         ($2,000,000). The waiver herein granted is not applicable if the Excess
         Availability is less than Two Million Dollars ($2,000,000) at any time
         after July 27, 2001.


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         (b) Administrative Agent and Lenders hereby grant a temporary,
         revocable waiver (the "Fifth TROL Default Waiver") with respect to the
         Event of Default existing on the date hereof under Section 11.10 of the
         Credit Agreement as a result of the fact that a TROL Default has
         occurred because of the existence of the Event of Default described in
         paragraph 2(a) of this Waiver and because of the failure of the
         Companies to maintain as of June 30, 2001 the leverage ratio required
         by Section 6.01 of the Amended and Restated Guaranty dated as of March
         22, 2000 given by Parent under the TROL Financing for the benefit of
         the TROL Lenders (the "TROL Guaranty"), the debt service coverage ratio
         required by Section 6.02 of the TROL Guaranty, the minimum net worth
         required by Section 6.03 of the TROL Guaranty. The Fifth TROL Default
         Waiver will automatically expire and terminate on the earlier of (1)
         the date on which Administrative Agent or either Lender exercises its
         unconditional revocation right pursuant to the next sentence hereof,
         (2) the date on which the TROL Lenders accelerate the maturity of the
         Lease Obligations (as defined in the TROL Guaranty) and (3) the date on
         which the TROL Lenders commence the exercise of any remedies under the
         TROL Financing Documents. Administrative Agent and each Lender hereby
         reserve the absolute and unconditional right to revoke the Fifth TROL
         Default Waiver at any time, in the sole discretion of Administrative
         Agent or either Lender, with or without cause, by giving verbal or
         written notice of such revocation to Borrower, effective immediately at
         the time such notice is given (with any verbal notice to be followed by
         written notice, but effective as of the time of the verbal notice).

3. Ratifications. Except as expressly supplemented by this Waiver, the Credit
Documents are ratified and confirmed and continue in full force and effect. The
Credit Documents continue to be legal, valid, binding and enforceable in
accordance with their respective terms. Without limiting the generality of the
foregoing, Borrower and Parent, and each Ratifying Subsidiary, hereby ratify and
confirm that all Liens heretofore granted to Administrative Agent for the
benefit of Lenders were intended to, do and continue to secure the full payment
and performance of the Obligation. Borrower and Parent agree to perform such
acts and duly authorize, execute, acknowledge, deliver, file and record such
additional assignments, security agreements, modifications or amendments to any
of the foregoing, and such other agreements, documents and instruments as
Administrative Agent may reasonably request in order to perfect and protect
those Liens and preserve and protect the Rights of Administrative Agent and
Lenders in respect of all present and future Collateral.

4. Representations and Warranties. Borrower and Parent hereby, jointly and
severally, represent and warrant to Administrative Agent and Lenders that (a)
this Waiver and any other Credit Documents to be delivered under this Waiver
have been duly executed and delivered by or on behalf of Borrower and each other
Company party to them, are valid and binding upon Borrower and the other
Companies and are enforceable against Borrower and the other Companies in
accordance with their respective terms, except as limited by any applicable
Debtor Relief Laws, (b) no action of, or filing with, any Governmental Authority
is required to authorize, or is otherwise required in connection with, the
execution, delivery and performance



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by Borrower or any other Company of this Waiver or any other Credit Document to
be delivered under this Waiver, (c) the execution, delivery and performance by
Borrower and the other Companies of this Waiver and any other Credit Documents
to be delivered under this Waiver do not require the consent of any other Person
and do not and will not constitute a violation of any Laws, agreements or
understandings to which Borrower or any other Company is a party or by which
Borrower or any other Company is bound, (d) the representations and warranties
contained in the Credit Agreement, as supplemented by this Waiver, and any other
Credit Documents are true and correct in all material respects as of the date of
this Waiver, (e) no Event of Default or Potential Default exists, other than the
Events of Default and Potential Defaults to which the First, Second, Third,
Fourth and Fifth TROL Default Waivers relate, (f) this Waiver does not and shall
not be deemed to be constitute a waiver of, consent to or acquiescence in any
Event of Default or Potential Default except as expressly stated herein, and (g)
each Company has performed all of its obligations under the Credit Agreement and
other Credit Documents.

5. Release of All Claims. Borrower, Parent and each Ratifying Subsidiary hereby,
jointly and severally, unconditionally release and forever discharge
Administrative Agent and each Lender and their respective successors, assigns,
agents, directors, officers, employees, affiliates, accountants, consultants,
contractors, advisors and attorneys (collectively, the "Benefited Parties") from
all Claims (as defined below) and jointly and severally agree to indemnify the
Benefited Parties, and hold them harmless from any and all claims, losses,
causes of action, costs and expenses of every kind or character in connection
with the Claims. As used in this Waiver, the term "Claims" means any and all
possible claims, demands, actions, causes of actions, costs, expenses and
liabilities whatsoever, known or unknown, at law or in equity, originating in
whole or in part, which Borrower, Parent or any Ratifying Subsidiary, or any of
their agents, employees or affiliates may now or hereafter have or claim against
any of the Benefited Parties and irrespective of whether any such Claims arise
out of contract, tort, violation of Law or otherwise in connection with any of
the Credit Documents, including any contracting for, charging, taking,
reserving, collecting or receiving interest in excess of the maximum rate on
interest chargeable under applicable Law and any loss, cost or damage, of any
kind or character, arising out of or in any way connected with or in any way
resulting from the actions or omissions of the Benefited Parties, including any
breach of fiduciary duty, breach of any duty of good faith or fair dealing,
breach of confidence, breach of funding commitment other than the express
funding commitments contained in the Credit Agreement, undue influence, duress,
economic coercion, conflict of interest, negligence, bad faith, malpractice,
violations of the Racketeer Influenced and Corrupt Organizations Act,
intentional or negligent infliction of mental distress, tortious interference
with contractual relations, tortious interference with corporate governance or
prospective business advantage, breach of contract, deceptive trade practices,
libel, slander, conspiracy or any claim for wrongfully accelerating any
obligations or wrongfully attempting to foreclose on any collateral. Borrower,
Parent and each Ratifying Subsidiary, jointly and severally, agree that none of
the Benefited Parties have fiduciary or similar obligations to Borrower, Parent
or any agents, employees or affiliates of Borrower or Parent and that their
relationships are strictly that of creditor and debtor. This release is accepted
by Administrative


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Agent and each Lender pursuant to this Waiver and shall not be construed as an
admission of liability by Administrative Agent, any Lender or any other
Benefited Party.

6. Counterparts. This Waiver may be executed in any number of counterparts with
the same effect as if all signatories had signed the same document.

7. Parties Bound. This Waiver binds and inures to the benefit of Borrower,
Lenders and Administrative Agent and, subject to Section 14.12 of the Credit
Agreement, their respective successors and assigns.

8. ENTIRETY. THIS WAIVER, THE CREDIT AGREEMENT AS SUPPLEMENTED BY THIS WAIVER,
AND THE OTHER CREDIT DOCUMENTS REPRESENT THE FINAL AGREEMENT BETWEEN THE PARTIES
FOR THE TRANSACTIONS HEREIN AND THEREIN, AND MAY NOT BE CONTRADICTED BY EVIDENCE
OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENT BETWEEN THE PARTIES.
THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

         Executed as of and effective as of July 20, 2001.

                  ULTRAK, INC., as Parent

                  By:  /s/ CHRIS T. SHARNG
                     --------------------------------------------------
                           Chris T. Sharng, Senior Vice President
                           and Chief Financial Officer

                  ULTRAK OPERATING, L.P. as Borrower
                  By: Ultrak GP, Inc. its General Partner

                  By:  /s/ CHRIS T. SHARNG
                     --------------------------------------------------
                           Chris T. Sharng, Senior Vice President
                           and Chief Financial Officer

                  AMERICAN NATIONAL BANK AND TRUST COMPANY OF CHICAGO
                           as Administrative Agent and a Lender

                  By:  /s/ DONNA H. EVANS
                     --------------------------------------------------
                           Donna H. Evans, Vice President

                  HARRIS TRUST AND SAVINGS BANK, as a Lender

                  By:  /s/ JAMES ANDRICOPULOS
                     --------------------------------------------------
                           James Andricopulos, Vice President




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                               SUBSIDIARY JOINDER

         To induce Administrative Agent and Lenders to enter into this Waiver,
each Subsidiary named below (a) consents and agrees to this Waiver's execution
and delivery, (b) ratifies and confirms that all guaranties, assurances and
Liens granted, conveyed or assigned to Administrative Agent for the benefit of
Lenders under the Credit Documents are not released, diminished, impaired,
reduced or otherwise adversely affected by this or any prior amendment, and
continue to guarantee, assure and secure the full payment and performance of the
Obligation, (c) agrees to perform such acts and duly authorize, execute,
acknowledge, deliver, file and record such additional guaranties, assignments,
security agreements, deeds of trust, mortgages and other agreements, documents,
instruments and certificates as Administrative Agent may reasonably deem
necessary or appropriate in order to create, perfect, preserve and protect those
guaranties, assurances and Liens, and (d) waives notice of acceptance of this
consent and agreement, which consent and agreement binds each of the undersigned
and their respective successors and permitted assigns and inures to the benefit
of Administrative Agent and Lenders and their respective successors and
permitted assigns.

                  ULTRAK GP, INC.

                  By:            /s/ CHRIS T. SHARNG
                     --------------------------------------------------
                           Chris T. Sharng, Senior Vice President
                           and Chief Financial Officer

                  ULTRAK, LP, INC.

                  By:            /s/ CHRIS T. SHARNG
                     --------------------------------------------------
                           Chris T. Sharng, Senior Vice President
                           and Chief Financial Officer

                  DIAMOND ELECTRONICS, INC.

                  By:            /s/ CHRIS T. SHARNG
                     --------------------------------------------------
                           Chris T. Sharng, Senior Vice President
                           and Chief Financial Officer

                  MONITOR DYNAMICS, INC.

                  By:            /s/ CHRIS T. SHARNG
                     --------------------------------------------------
                           Chris T. Sharng, Senior Vice President
                           and Chief Financial Officer

                  ABM DATA SYSTEMS, INC.

                  By:            /s/ CHRIS T. SHARNG
                     --------------------------------------------------
                           Chris T. Sharng, Senior Vice President
                           and Chief Financial Officer

                  SECURITY WARRANTY, INC.

                  By:            /s/ CHRIS T. SHARNG
                     --------------------------------------------------
                           Chris T. Sharng, Senior Vice President
                           and Chief Financial Officer

                  SECURITY WARRANTY (BVI) LTD.

                  By:            /s/ CHRIS T. SHARNG
                     --------------------------------------------------
                           Chris T. Sharng, Director




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