Exhibit 3(a)2
                             AMENDED AND RESTATED

                          ARTICLES OF INCORPORATION

                                      OF

                     SOUTHWESTERN PUBLIC SERVICE COMPANY


      Pursuant to  Sections  53-13-4  and -7, New Mexico  Statutes  Annotated,
Southwestern   Public  Service   Company,   a  New  Mexico   corporation  (the
"Corporation"),  hereby amends and restates its Articles of Incorporation,  as
previously amended and restated, as follows:

      FIRST:  Name.  The  name  of  the  Corporation  is  Southwestern  Public
Service Company.

      SECOND:  Principal  New Mexico  Office.  The  location of the  principal
office of the  Corporation in New Mexico shall be at 111 East Fifth,  Roswell,
New Mexico.

      THIRD:  Purpose.  The purpose for which the  Corporation is organized is
to  transact  any  and all  lawful  business  for  which  corporations  may be
incorporated under the New Mexico Business Corporation Act (the "NMBCA").

      FOURTH:  Capital  Stock.  The total number of  authorized  shares of the
Corporation  shall be 10,000,200,  divided into  10,000,000  preferred  shares
having a par value of $1 per share  (the  "Preferred  Stock")  and 200  common
shares having a par value of $1 per share (the "Common Stock").

      The   designations,    voting   powers,   preferences,   and   relative,
participating,   optional,   or  other  special  rights,  and  qualifications,
limitations, or restrictions of the above classes of stock are as follows:

      (A)   Preferred Stock

            (1)   Issuance  in  Series.  Shares  of  Preferred  Stock  may  be
      issued  in one or  more  series  when  and  for  such  consideration  or
      considerations  as the Board of  Directors  determines.  All series will
      rank equally and be identical  in all  respects,  except as permitted by
      the following provisions of paragraph 2 of this Article Fourth (A).

            (2)   Authority  of the Board with  Respect  to Series.  The Board
      of Directors is authorized,  at any time, to provide for the issuance of
      the  shares  of  Preferred   Stock  in  one  or  more  series  with  the
      designations,  voting powers, preferences, and relative,  participating,
      optional, or other special rights, and qualifications,  limitations,  or
      restrictions  thereof as are  stated in the  resolution  or  resolutions
      providing for the issue thereof  adopted by the Board of Directors,  and
      as  are  not  stated  in  these   Amended  and   Restated   Articles  of
      Incorporation  or any amendment  hereto or not  otherwise  prescribed by
      law  including,  but  not  limited  to,  determination  of  any  of  the
      following:
<PAGE>

                  (i) The maximum  number of shares to constitute  the series,
            which may  subsequently  be increased or decreased  (but not below
            the  number  of  shares  of  such  series  then   outstanding)  by
            resolution  of  the  Board  of  Directors   and  the   distinctive
            designation thereof;

                  (ii)  Whether  the  shares  of the  series  shall  have  any
            voting powers,  in addition to the voting powers  provided by law,
            and, if any, the terms of the voting powers;

                  (iii) The dividend  rate or rates,  if any, on the shares of
            the  series  or the  manner in which  such rate or rates  shall be
            determined,  the  conditions  and dates upon  which the  dividends
            shall  be  payable,  and the  preference  or  relation  which  the
            dividends  shall bear to the dividends  payable on any other class
            or classes or on any other  series of capital  stock,  and whether
            the dividends shall be cumulative or noncumulative;

                  (iv)  Whether  the shares of the series  shall be subject to
            redemption   by  the   Corporation,   and,  if  made   subject  to
            redemption,  the  times,  prices,  and other  terms,  limitations,
            restrictions, or conditions of the redemption;

                  (v)  The  relative  amounts,  and  the  relative  rights  or
            preferences,  if any,  of  payment  in  respect  of  shares of the
            series,  which  the  holders  of  shares  of the  series  shall be
            entitled to receive upon the liquidation,  dissolution, or winding
            up of the Corporation;

                  (vi)  Whether  the shares of the series  shall be subject to
            the  operation  of a  retirement  or sinking  fund and, if so, the
            extent to which and the manner in which any  retirement or sinking
            fund shall be applied to the purchase or  redemption of the shares
            of the series for retirement or for other corporate purposes,  and
            the  terms  and  provisions  relative  to  the  operation  of  the
            retirement or sinking fund;

                  (vii)   Whether   the   shares  of  the   series   shall  be
            convertible  into, or exchangeable for, shares of any other class,
            classes, or series, or other securities,  whether or not issued by
            the Corporation, and if so convertible or exchangeable,  the price
            or prices or the rate or rates of  conversion  or exchange and the
            method, if any, of adjusting them;

                  (viii)  The  limitations  and  restrictions,  if any,  to be
            effective while any shares of the series are outstanding  upon the
            payment of dividends or the making of other  distributions on, and
            upon  the  purchase,  redemption,  or  other  acquisition  by  the
            Corporation  of, the Common Stock or any other class or classes of
            stock of the  Corporation  ranking  junior  to the  shares  of the
            series  either as to dividends or upon  liquidation,  dissolution,
            or winding up of the Corporation;
                                       2

<PAGE>

                  (ix)  The  conditions  or  restrictions,  if any,  upon  the
            creation of  indebtedness  of the Corporation or upon the issuance
            of any  additional  stock  (including  additional  shares  of such
            series or of any other  class)  ranking on a parity  with or prior
            to the shares of the series as to  dividends  or  distribution  of
            assets  upon  liquidation,  dissolution,  or  winding  up  of  the
            Corporation; and

                  (x)   Any   other   preference,   relative,   participating,
            optional,   or  other  special  rights,  and  the  qualifications,
            limitations,  or restrictions  thereof, not inconsistent with law,
            this Article  Fourth,  or any resolution of the Board of Directors
            pursuant hereto.

            (3)   Preemptive  Rights.  The  holders  of  the  Preferred  Stock
      shall have no  preemptive  rights to subscribe to any issue of shares or
      other securities of any class of the Corporation.

      (B)   Common Stock

            (1)   Dividends.  Subject  to the  preferential  rights of holders
      of the Preferred Stock,  dividends may be paid or declared and set apart
      for payment  upon the Common  Stock out of any funds  legally  available
      for the  declaration  of  dividends,  but only when and as determined by
      the Board of Directors.

            (2)   Liquidation,  Dissolution,  or  Winding  Up.  Subject to the
      preferential  rights of holders of the  Preferred  Stock in the event of
      any voluntary or involuntary liquidation,  dissolution, or winding up of
      the  Corporation,  the  holders of shares of the Common  Stock  shall be
      entitled to receive all of the assets of the  Corporation  available for
      distribution to its shareholders  ratably in proportion to the number of
      shares of the Common Stock they hold.

            (3)   Voting  Rights.  Except as may be otherwise  required by the
      NMBCA or these  Amended and  Restated  Articles of  Incorporation,  each
      holder  of Common  Stock has one vote for each  share of stock he or she
      holds of record on the books of the  Corporation  on all  matters  voted
      upon  by  the  shareholders.  Cumulative  voting  for  the  election  of
      directors shall not be permitted.

            (4)   Preemptive  Rights.  The  holders of the Common  Stock shall
      have no  preemptive  rights to subscribe to any issue of shares or other
      securities of any class of the Corporation.

      FIFTH:  Duration.  The duration of the Corporation shall be perpetual.

      SIXTH:  Number of Directors.  The number of directors  shall be fixed as
provided in the Bylaws of the  Corporation  (the  "Bylaws")  or, if the Bylaws
fail to fix the number,  by resolution  adopted from time to time by the Board
of Directors.
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<PAGE>

      SEVENTH:  Limitations of Liability;  Indemnification.  A director of the
Corporation  shall  not be  personally  liable  to the  Corporation  or to its
shareholders  for  monetary  damages  for a  breach  of  fiduciary  duty  as a
director  unless (a) he or she has breached or failed to perform the duties of
his or her office in accordance with the NMBCA,  and (b) the breach or failure
to perform constitutes  negligence,  willful misconduct,  or recklessness.  If
the NMBCA is amended to permit the further  elimination  or  limitation of the
personal  liability  of  directors,  then the  liability  of a director of the
Corporation  shall be eliminated or limited to the fullest extent permitted by
the NMBCA, as amended.

      To the maximum extent permitted by law, the Corporation  shall indemnify
any person who is or was a director,  officer,  agent,  fiduciary, or employee
of the  Corporation  against any claim,  liability,  loss, or expense  arising
against  or  incurred  by such  person as a result of  circumstances,  events,
actions,  and omissions  occurring in such capacity.  The Corporation  further
shall have the authority to maintain  insurance at the  Corporation's  expense
providing  for such  indemnification,  including  insurance  with  respect  to
claims, liabilities,  losses, and expenses against which the Corporation would
not otherwise have the power to indemnify such persons.

      Any repeal or modification  of this Article Seventh by the  shareholders
of the  Corporation  shall not  adversely  affect any right or protection of a
director,  officer,  agent,  fiduciary,  or  employee  of the  Corporation  in
respect of any act or  omission  occurring  prior to the time of the repeal or
modification.

      EIGHTH:  Bylaws.  In  furtherance  and not in  limitation  of the powers
conferred by statute,  the Board of Directors is  authorized to make and alter
the Bylaws,  subject to the power of the  shareholders to alter and repeal the
Bylaws made by the Board of Directors.

                                  * * * * *

      The foregoing  Amended and Restated  Articles of  Incorporation  include
amendments  to  the  Corporation's  previous  Articles  of  Incorporation,  as
amended.  These  amendments  were duly  approved  and  adopted by the Board of
Directors of the Corporation effective August 26, 1997.

      The sole  shareholder  of the  Corporation,  owning 100 shares of common
stock of the  Corporation,  duly approved the  foregoing  Amended and Restated
Articles of  Incorporation  (including  the amendments  reflected  therein) by
written  consent  effective  August 26, 1997. All such shares were eligible to
vote on the  amendment as a single  class,  and all such shares were voted for
and none against  such  amendments.  No other  shares of capital  stock of the
Corporation were or are outstanding.
                                       4

<PAGE>

      These  Amended and  Restated  Articles of  Incorporation  correctly  set
forth  the  corresponding  provisions  of the  Articles  of  Incorporation  as
amended and supersede  the original  Articles of  Incorporation  and all prior
amendments thereto.

      Dated:  September 30, 1997.

                                           SOUTHWESTERN PUBLIC SERVICE COMPANY



                                    By               /s/ David M. Wilks       
                                                David M. Wilks, President


                                    By                /s/ Mary Pullum         
                                                 Mary Pullum, Secretary


STATE OF TEXAS          )
                        ) ss.
COUNTY OF POTTER  )

      David M. Wilks,  being first duly sworn,  states that he is President of
Southwestern  Public  Service  Company,  that  he  has  read  and  signed  the
foregoing  document,  and that every  statement  in the  document  is true and
correct to the best of his information and belief.


                                                /s/ David M. Wilks            
                                                  David M. Wilks


SWORN  AND  SUBSCRIBED  TO  BEFORE  ME BY  David M.  Wilks,  as  President  of
Southwestern Public Service Company, on this 30th day of September 1997.



                                                /s/ Teresa Joan Parker        
                                    Teresa Joan Parker
                                    Notary Public, State of Texas
                                    My commission expires:  May 19, 2001


[NOTARIAL SEAL]

[Filed in the office of the State
 Corporation Commission of
 New Mexico and made effective
 on October 1, 1997.]

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