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                                                                   EXHIBIT 3.7


                            ARTICLES OF INCORPORATION

                                       OF

                              ASTRA SERVICES, INC.


         The undersigned sole incorporator hereby undertakes to form and
establish a corporation FOR PROFIT under the laws of the State of Kansas.

         FIRST: The name of the Corporation is ASTRA SERVICES, INC.

         SECOND: The location of its registered office in this state is 818
Kansas Avenue, Topeka, Shawnee County, Kansas, 66612.

         THIRD: The name and address of its resident agent in this state is
Stacy F. Kramer, 818 Kansas Avenue, Topeka, Shawnee County, Kansas 66612.

         FOURTH: This Corporation is organized FOR PROFIT and the nature of its
business is to engage in any lawful act or activity for which corporations may
be organized under the Kansas General Corporation Code. Provided however, this
Corporation may not engage in the business of an electric or retail natural gas
utility.

         FIFTH: The Corporation is authorized to issue only one class of common
stock. The total number of shares of stock which the Corporation shall have
authority to issue shall be ONE THOUSAND (1,000) Shares of NO PAR VALUE COMMON
STOCK. Such shares may be issued for such consideration as is determined from
time to time by the Board of Directors of the Corporation.

         SIXTH: The business and affairs of the Corporation shall be managed by
its Board of Directors. The powers of the Incorporator are to terminate upon the
filing of the ARTICLES OF INCORPORATION with the Secretary of State. The name
and mailing address of the person who is to serve as sole Director until the
first meeting of Stockholders or until his successor is duly elected and
qualified is:



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                               Richard D. Terrill
                             6315 South Pointe Drive
                              Auburn, Kansas 66402

         The number of Directors, if more than one, shall be fixed by, or in the
manner provided in, the BYLAWS of the Corporation. Directors need not be
Stockholders of the Corporation.

         SEVENTH: The name and mailing address of the sole incorporator is:

                                 Stacy F. Kramer
                           3039 SW Staffordshire Road
                              Topeka, Kansas 66614

         EIGHTH: For the management of the business and for the conduct of the
affairs of the Corporation, and in further definition, limitation and regulation
of the powers of the Corporation and its Directors and Stockholders, it is
further provided:

         a. In furtherance, and not in limitation of the powers conferred by the
laws of the State of Kansas, the Board of Directors is expressly authorized and
empowered:

         (1) To make, alter, amend or repeal the Bylaws in any manner not
inconsistent with the laws of the State of Kansas or these Articles of
Incorporation, subject to the power of the Stockholders to amend, alter or
repeal the Bylaws made by the Board of Directors or to limit or restrict the
power of the Board of Directors so to make, alter, amend or repeal the Bylaws;

         (2) Without the assent or vote of the Stockholders, to authorize and
issue obligations of the Corporation, secured or unsecured, to include therein
such provisions as to redeemability, convertibility or otherwise, as the Board
of Directors in its sole discretion may determine, and to authorize the
mortgaging or pledging, as security therefor, of any property of the
Corporation, real or personal, including after-acquired property;

         (3) To determine the manner in which the votes of Stockholders for the
election of Directors shall be evidenced, which need not be by written ballot.




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         b. Any Director or any Officer elected or appointed by the Stockholders
or by the Board of Directors may be removed at any time in such manner as shall
be provided in the Bylaws of the Corporation.

         c. The holders of this Corporation's Common Stock shall not have
preemptive rights.

         d. Whenever a compromise or arrangement is proposed between this
Corporation and its creditors or any class of them or between this Corporation
and its Stockholders or any class of them, any court of competent jurisdiction
within the State of Kansas, on the application in a summary way of this
Corporation or of any creditor or Stockholder thereof or on the application of
any receiver or receivers appointed for this Corporation under the provisions of
K.S.A. 17-6901 or on the application of trustees in dissolution or of any
receiver or receivers appointed for this Corporation under the provisions of
K.S.A. 17-6808, may order a meeting of the creditors or class of creditors, or
of the Stockholders or class of Stockholders of this Corporation, as the case
may be, to be summoned in such manner as said court directs. If a majority in
number representing three-fourths in value of the creditors or class of
creditors, or of the Stockholders or class of Stockholders of this Corporation,
as the case may be, agree to any compromise or arrangement and to any
reorganization of this Corporation as consequence of such compromise or
arrangement, said reorganization, if sanctioned by the court to which said
application has been made, shall be binding on all the creditors or class of
creditors, or on all the Stockholders or class of Stockholders of this
Corporation, as the case may be, and also on this Corporation.

         NINTH: A Director of this Corporation shall have no personal liability
to the Corporation or its Stockholders for monetary damages for breach of
fiduciary duty as a Director except to the extent that K.S.A. 17-6002(b)(8) (or
any successor provision of the Kansas General Corporation Code), as amended from
time to time, expressly provides that the liability of a Director may not be
eliminated or limited.


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         TENTH: To the extent permitted by the Kansas General Corporation Code,
any action which may be taken at any annual or special meeting of either
stockholders or directors may be taken without a meeting, without prior notice
and without a vote if a consent in writing, setting forth the action taken is
signed by (i) all of the holders of the Corporation's issued and outstanding
shares in the case of the Stockholders or (ii) all of the duly elected and
serving Directors, in the case of the Directors.

         IN WITNESS WHEREOF, I have hereunto subscribed my name as sole
incorporator this 19th day of April, 1995.


                                 /s/ STACY F. KRAMER
                                 ----------------------------------
                                 Stacy F. Kramer

STATE OF KANSAS   )
                  ) ss:
COUNTY OF SHAWNEE )

         BE IT REMEMBERED, that on this 19th of April, 1995, before me, the 
undersigned, a Notary Public in and for the County and State aforesaid, came
Stacy F. Kramer who personally is known to me to be the same person who executed
the foregoing ARTICLES OF INCORPORATION and duly acknowledged the execution of
the same as her free and voluntary act and deed.

         IN WITNESS WHEREOF, I have hereto set my hand affixed my notarial seal
the day and year last above written.


                                 /s/ REGINA I. DeGARMO
                                 -----------------------------------
                                 Notary Public
My Appointment expires:
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                         CERTIFICATE OF AMENDMENT TO THE
                          ARTICLES OF INCORPORATION OF
                              ASTRA SERVICES, INC.

         We, Steven A. Millstein, President, and Robert J. Knott, Secretary of
the above named corporation, a corporation organized and existing under the laws
of the State of Kansas, do hereby certify that a unanimous written consent of
the Board of Directors of said corporation, was adopted setting forth the
following amendment to the Articles of Incorporation and declaring their
advisability:

                  Resolved, That the following amendment of the Company's
                  Articles of Incorporation be, and it hereby is proposed and
                  declared advisable:

                  The following paragraph be included as a replacement for the
                  existing paragraph of Article First of the Articles of
                  Incorporation and read as follows:

                  The name of the corporation is Westar Consumer Services, Inc.

         We further certify that thereafter, pursuant to said resolution, and in
accordance with the by-laws of the corporation and the laws of the State of
Kansas, the Board of Directors called a meeting of stockholders for
consideration of the proposed amendments, and thereafter, pursuant to notice and
in accordance with the statutes of the State of Kansas, the stockholders
convened and considered the proposed amendments.

         We further certify that at the meeting a majority of the stockholders
entitled to vote voted in favor of the proposed amendments.

         We further certify that the amendments were duly adopted in accordance
with the provision of K.S.A. 17-6602, as amended.

         We further certify that the capital of said corporation will not be
reduced under or by reason of said amendments.



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         IN WITNESS WHEREOF, we have hereunto set our hands and affixed the seal
of said corporation the 29th day of November, 1995.


                                        /s/ STEVEN A. MILLSTEIN
                                        ---------------------------------------
                                        Steven A. Millstein
                                        President


                                        /s/ Robert J. Knott
                                        ---------------------------------------
                                        Robert J. Knott
                                        Secretary


STATE OF KANSAS                     )
                                    )
COUNTY OF SHAWNEE                   )


         Be it remembered that before me, a Notary Public in and for the
aforesaid county and state, personally appeared Steven A. Millstein, President
and Robert J. Knott, Secretary of the corporation named in this document, who
are known to me to be the same persons who executed the foregoing certificate
and duly acknowledge the execution of the same this 29th day of November, 1995.



                                        /s/ Tracy E. Hill
                                        ---------------------------------------
                                        Notary Public



                                        2


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                         CERTIFICATE OF AMENDMENT TO THE
                          ARTICLES OF INCORPORATION OF
                         WESTAR CONSUMER SERVICES, INC.

         We, Steven A. Millstein, President, and Marilyn K. Dalton, Secretary of
the above named corporation, a corporation organized and existing under the laws
of the State of Kansas, do hereby certify that a unanimous written consent of
the Board of Directors of said corporation, was adopted setting forth the
following amendment to the Articles of Incorporation and declaring their
advisability

                  Resolved, that the following amendment of the Company's
                  Articles of Incorporation be, and hereby is, proposed and
                  declared advisable

                  Article First of the Articles of Incorporation be amended in
                  its entirety to read as follows:

                  The name of the corporation is Westar Security, Inc.

         We further certify that thereafter, pursuant to said resolution, and in
accordance with the by-laws of the corporation and the laws of the State of
Kansas, the Board of Directors called a meeting of shareholders for
consideration of the proposed amendments, and thereafter, pursuant to notice and
in accordance with the statutes of the State of Kansas, the shareholders
convened and considered the proposed amendments.

         We further certify that at the meeting a majority of the shareholders
entitled to vote voted in favor of the proposed amendments.

         We further certify that the amendments were duly adopted in accordance
with the provision of K.S.A. 17-6602, as amended.

         We further certify that the capital of said corporation will not be
reduced under or by reason of said amendments.



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         IN WITNESS WHEREOF, we have hereunto set our hands and affixed the seal
of said corporation the 22nd day of July, 1996.





                                        /s/ STEVEN A. MILLSTEIN               
                                        ---------------------------------------
                                        Steven A. Millstein
                                        President


                                        /s/ MARILYN K. DALTON
                                        ---------------------------------------
                                        Marilyn K. Dalton
                                        Secretary


STATE OF KANSAS                     )
                                    )
COUNTY OF SHAWNEE                   )


         Be it remembered that before me, a Notary Public in and for the
aforesaid county and state, personally appeared Steven A. Millstein, President
and Marilyn K. Dalton, Secretary of the corporation named in this document, who
are known to me to be the same persons who executed the foregoing certificate
and duly acknowledge the execution of the same this 22nd day of July, 1996.




                                        /s/ Tracy E. Hill
                                        ---------------------------------------
                                        Notary Public



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                       CERTIFICATE OF OWNERSHIP AND MERGER
                                       OF
                       CENTENNIAL SECURITY HOLDINGS, INC.
                                  WITH AND INTO
                              WESTAR SECURITY, INC.

                   (UNDER K.S.A. 17-6703 OF THE KANSAS GENERAL
                 CORPORATION CODE AND SECTION 253 OF THE GENERAL
                    CORPORATION LAW OF THE STATE OF DELAWARE)

         --------------------------------------------------------------


WESTAR SECURITY, INC. hereby certifies that:

         (1) The name and state of incorporation of each of the constituent
corporations are:

                  (a)      Centennial Security Holdings, Inc., a Delaware
                           corporation and a wholly-owned subsidiary of Westar
                           Security, Inc. ("Subsidiary"), and
                  (b)      Westar Security, Inc., a Kansas corporation ("Parent"
                           or the "Surviving Corporation").

         (2) Parent owns one hundred percent (100%) of the issued and
outstanding shares of capital stock of Subsidiary.

         (3) Pursuant to K.S.A. 17-6703 of the Kansas General Corporation Code
and Section 253 of the General Corporation Law of the State of Delaware, the
Board of Directors of Parent adopted resolutions authorizing the merger of
Subsidiary with and into Parent by unanimous written consent. A copy of such
resolutions dated as of March 27, 1998 is attached as Exhibit A hereto.

         (4) The name of the surviving corporation is Westar Security, Inc.

         (5) The Certificate of Incorporation of Westar Security, Inc. shall be
the Certificate of Incorporation of the surviving corporation.

         (6) The Surviving Corporation hereby agrees that it may be served with
process in the State of Delaware in any proceeding for enforcement of any
obligation of Centennial Security Holdings, Inc., as well as for enforcement of
any obligation of the Surviving Corporation arising from the merger, including
any suit or other proceeding to enforce the right of any stockholders as
determined in appraisal procedures pursuant to Section 262 of



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the DGCL, and shall irrevocably appoint the Secretary of State of Delaware as
its agent to accept service of process in any such suit or other proceedings. A
copy of such service of process shall be mailed to Protection One, Inc., 4221 W.
John Carpenter Freeway, Irving, Texas 75063-2924, Attn: Legal Department.

         (7) The effective date of the merger shall be 4:00 p.m. Central
Standard Time, on March 31, 1998.




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         IN WITNESS WHEREOF, Parent has caused this certificate to be signed by
Steve Millstein, its President, on the 27th day of March, 1998.

                                         WESTAR SECURITY, INC.


                                         By:  /s/ STEVEN A. MILLSTEIN
                                            -----------------------------------
                                                  Steven A. Millstein, President


                                         ATTEST:


                                         By:  /s/ JOHN HESSE
                                            -----------------------------------
                                                  John Hesse, Secretary


STATE OF TEXAS                      )
                                    )
COUNTY OF DALLAS                    )


         Before me, a Notary Public in and for the aforesaid county and state,
personally appeared Steven A. Millstein and John Hesse, President and Secretary,
respectively, of Westar Security, Inc., a Kansas corporation, who are known to
me to be the same persons who executed the foregoing Certificate and duly
acknowledge the execution of the same this 27th day of March, 1998.



                                        /s/ WENDY WILKES
                                        ---------------------------------------
                                        Notary Public

                                        Commission expires:

                                        10-11-2000
                                        ---------------------------------------




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                                    EXHIBIT A

                             RESOLUTIONS ADOPTED BY
                 THE BOARD OF DIRECTORS OF WESTAR SECURITY, INC.
                              AS OF MARCH 27, 1998

         BE IT RESOLVED, that the Board of Directors of Westar Security, Inc., a
Kansas corporation (the "Corporation"), in its best business judgment deems it
advisable and in the best interests of the Corporation and its sole shareholder
that Centennial Security Holdings, Inc., a Delaware corporation ("Subsidiary")
and a wholly-owned subsidiary of the Corporation, shall be merged with and into
the Corporation (the "Merger"), and hereby approves the Merger in all respects.

         RESOLVED FURTHER, that Subsidiary shall be merged with and into the
Corporation pursuant to the provisions of K.S.A. 17-6703 of the Kansas General
Corporation Code ("KGCC") Section 253 of the Delaware General Corporation Law
(the "DGCL"), and that in the Merger the Corporation shall be the surviving
corporation.

         RESOLVED FURTHER, that the effective date (the "Effective Date") of the
Merger shall be 4:00 p.m., Central Standard Time, on March 31, 1998.

         RESOLVED FURTHER, that in accordance with the KGCC and the DGCL, on the
Effective Date of the Merger the separate existence of Subsidiary shall cease,
and the Corporation and Subsidiary shall then and thereafter together comprise a
single corporation, which shall be the Corporation; the Corporation shall have
all the rights and privileges, immunities and powers and shall be subject to all
of the duties and liabilities of a corporation organized under the KGCC; the
Corporation shall thereupon and thereafter possess all the rights, privileges
and franchises of the Corporation and Subsidiary; all property (real, personal
and mixed), all debts due on whatever account, all claims and all other
interests of or belonging to or due to Subsidiary shall be taken and deemed to
be transferred to and vested in the Corporation without further act or deed; the
Corporation shall thenceforth be responsible and liable for all liabilities and
obligations of Subsidiary; any claim existing or action or proceeding pending by
or against Subsidiary may be prosecuted as if the Merger had not taken place, or
the Corporation may be substituted in the place of Subsidiary; and neither the
rights of creditors nor any liens upon the property of the Corporation or
Subsidiary shall be impaired by the Merger.



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         RESOLVED FURTHER, that each outstanding share of the capital stock of
the Corporation shall continue to be an outstanding share of capital stock of
the Corporation after the Effective Date of the Merger.

         RESOLVED FURTHER, that all of the outstanding shares of capital stock
of Subsidiary owned by the Corporation on the Effective Date of the Merger
shall, by virtue of the Merger, be canceled and retired; all certificates
representing such share shall be canceled; and no cash, securities or other
property shall be issued in respect of such shares by reason of the Merger.

         RESOLVED FURTHER, that no changes in the Articles of Incorporation, the
By-laws, the directors or the officers of the Corporation shall be effected by
the Merger.

         RESOLVED FURTHER, the officers of the Corporation are hereby authorized
in the name and on behalf of the Corporation to execute and file with the
Secretary of State of Kansas and the Secretary of State of Delaware appropriate
Articles of Merger or other statement for the purpose of effectuating the Merger
in accordance with the preceding resolutions.

         RESOLVED FURTHER, that the proper officers of the Corporation are
hereby authorized and directed in the name and on behalf of the Corporation to
execute, acknowledge, certify, deliver, file, record and accept all such further
instruments and documents and to do or cause to be done any and all other acts
which in their judgment may be necessary or appropriate in order to effectuate
the Merger in accordance with the preceding resolutions and the applicable
provisions of the KGCC and the DGCL.




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