CENTRAL POWER AND LIGHT COMPANY


                                       AND


                              THE BANK OF NEW YORK,
                                   as Trustee

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


                          First Supplemental Indenture

                             Dated as of May 1, 1997


                                       TO


                                    INDENTURE


                             Dated as of May 1, 1997

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


       8.00% Junior Subordinated Deferrable Interest Debentures, Series A





<PAGE>






                  FIRST  SUPPLEMENTAL  INDENTURE,  dated as of the  first day of
May, 1997 (the "First Supplemental Indenture"),  between CENTRAL POWER AND LIGHT
COMPANY,  a corporation  duly organized and existing under the laws of the State
of Texas (hereinafter  sometimes referred to as the "Company" or "CPL"), and THE
BANK OF NEW  YORK,  a New York  banking  corporation,  as  trustee  (hereinafter
sometimes  referred to as the "Trustee") (under the Indenture dated as of May 1,
1997 between the Company and the Trustee (the "Indenture").


                  WHEREAS,  the Company  executed and delivered the Indenture to
the  Trustee  to  provide  for the future  issuance  of its junior  subordinated
debentures (the  "Debentures"),  which  Debentures are to be issued from time to
time in such series as may be determined by the Company under the Indenture,  in
an unlimited aggregate principal amount which may be authenticated and delivered
thereunder as in the Indenture provided; and

                  WHEREAS,  pursuant to the terms of the Indenture,  the Company
desires to provide for the establishment of a new series of its Debentures to be
known as its 8.00% Junior Subordinated Deferrable Interest Debentures,  Series A
(such series being hereinafter referred to as the "Series A Debentures"),  which
Series A Debentures will be issued to evidence a loan made to the Company of the
proceeds  from the  issuance  by CPL Capital I, a Delaware  business  trust (the
"Trust"), of preferred undivided beneficial interests in the assets of the Trust
(the "Preferred  Securities") and common undivided  beneficial  interests in the
assets  of the  Trust  (the  "Common  Securities")  pursuant  to the terms of an
Amended and Restated Trust Agreement (the "Trust  Agreement") dated as of May 1,
1997 among the Company, as Depositor, The Bank of New York, as Property Trustee,
The Bank of New York  (Delaware),  as Delaware  Trustee  and the  Administrative
Trustees named therein (the  "Administrative  Trustees"),  which Trust Agreement
shall be  substantially  in the form  attached  hereto  as Annex A, the form and
substance of such Series A Debentures  and the terms,  provisions and conditions
thereof to be set forth as provided in the Indenture and this First Supplemental
Indenture; and

                  WHEREAS,  the Company desires and has requested the Trustee to
join with it in the execution and delivery of this First Supplemental Indenture,
and all requirements necessary to make this First Supplemental Indenture a valid
instrument,  in accordance with its terms,  and to make the Series A Debentures,
when executed by the Company and authenticated and delivered by the Trustee, the
valid  obligations of the Company,  have been  performed and fulfilled,  and the
execution and delivery hereof have been in all respects duly authorized;

                  NOW,   THEREFORE,   in   consideration  of  the  purchase  and
acceptance  of the  Series A  Debentures  by the  holders  thereof,  and for the
purpose of setting forth,  as provided in the Indenture,  the form and substance
of the Series A Debentures and the terms, provisions and conditions thereof, the
Company covenants and agrees with the Trustee as follows:

                                   ARTICLE ONE
                             Additional Definitions

                  SECTION  1.01.  For all  purposes  of this First  Supplemental
Indenture,  capitalized  terms used  herein  without  definition  shall have the
meanings specified in the Indenture.

                  SECTION  1.02.  The terms  defined  in this  Section,  for all
purposes  of this  First  Supplemental  Indenture,  shall  have  the  respective
meanings specified in this Section.

                  "Additional Sums" has the meaning specified in Section 5.05 of
this First Supplemental Indenture.

                  "Additional  Taxes"  means  the sum of any  additional  taxes,
duties and other governmental charges to which the Trust has become subject from
time to time as a result of a Tax Event.

                  "Common  Securities"  has the meaning  specified in the second
recital of this First Supplemental Indenture.

                  "Distributions"  means  amounts  payable  in  respect  of  the
Preferred Securities and Common Securities as provided in the Trust Agreement.

                  "Extension  Period' has the meaning  specified in Section 4.01
of this First Supplemental Indenture.

                  "Guarantee"   means   the   guarantee   by  the   Company   of
Distributions on the Preferred Securities of the Trust to the extent provided in
the Guarantee Agreement, substantially in the form attached hereto as Annex B.

                  "Investment Company Event" means, in respect of the Trust, the
receipt by the Trust of an Opinion of  Counsel,  rendered by a law firm having a
recognized national tax and securities practice, to the effect that, as a result
of the occurrence of a change in law or regulation or a change in interpretation
or application of law or regulation by any legislative body, court, governmental
agency or regulatory authority (a "Change in 1940 Act Law), the Trust is or will
be considered an  "investment  company" that is required to be registered  under
the 1940 Act,  which  Change in 1940 Act Law becomes  effective  on or after the
date of original issuance of the Preferred Securities of the Trust.

                  "1940  Act"  means  the  Investment  Company  Act of 1940, as
amended.

                  "Preferred Securities" has the meaning specified in the second
recital of this First Supplemental Indenture.

                  "Property  Trustee"  means,  in  respect  of  the  Trust,  the
commercial bank or trust company identified as the Property Trustee in the Trust
Agreement,  solely in its  capacity as  Property  Trustee of the Trust under the
Trust Agreement and not in its individual capacity, or its successor in interest
in such  capacity,  or any  successor  property  trustee  appointed  as  therein
provided.

                  "Special  Event" means  a Tax Event or an  Investment  Company
Event.

                  "Tax  Event"  means the  receipt by the Trust of an Opinion of
Counsel,  rendered by a law firm having a recognized national tax and securities
practice,  to the  effect  that,  as a result  of any  amendment  to,  or change
(including any announced  prospective  change) in, the laws (or any  regulations
thereunder)  of  the  United  States  or any  political  subdivision  or  taxing
authority  thereof or  therein,  or as a result of any  official  administrative
pronouncement  or  judicial  decision  interpreting  or  applying  such  laws or
regulations,  which amendment or change is effective or which  pronouncement  or
decision  is  announced  on or  after  the  date of  issuance  of the  Preferred
Securities of the Trust,  there is more than an insubstantial  risk that (i) the
Trust  is, or will be within  90 days of the date of such  Opinion  of  Counsel,
subject to United States federal  income tax with respect to income  received or
accrued on the corresponding  Series A Debentures,  (ii) interest payable by the
Company on the Series A Debentures is not, or within 90 days of the date of such
Opinion of Counsel,  will not be,  deductible  by CPL, in whole or in part,  for
United  States  federal  income tax  purposes  or (iii) the Trust is, or will be
within 90 days of the date of such Opinion of Counsel, subject to more than a de
minimis amount of other taxes, duties or other governmental charges.

                  "Trust"  has  the meaning  specified in  the second recital of
this First Supplemental Indenture.

                  "Trust  Agreement"  has the  meaning  specified  in the second
recital of this First Supplemental Indenture.


                                   ARTICLE TWO
                         General Terms and Conditions of
                             the Series A Debentures

                  SECTION 2.01. There shall be and is hereby authorized a series
of Debentures  designated  the "8.00% Junior  Subordinated  Deferrable  Interest
Debentures,  Series A," limited in aggregate  principal  amount to $154,639,200,
which amount  shall be as set forth in any written  order of the Company for the
authentication  and  delivery of Series A  Debentures.  The Series A  Debentures
shall  mature and the  principal  shall be due and  payable,  together  with all
accrued  and unpaid  interest  thereon,  on April 30,  2037,  provided  that the
Company may shorten such  maturity date at any time and from time to time at the
election of the  Company,  but in no event shall such  maturity  date be earlier
than April 30, 2002,  and further  provided  that if the Company  exercises  its
right to liquidate  the Trust and  distribute  the  Debentures to holders of the
Preferred  Securities  pursuant  to  Section  904 of the  Trust  Agreement,  the
maturity  date of such  Debentures  may be shortened to any date selected by the
Company  that is (i) no  earlier  than the date five  years  after  the  initial
issuance of the Preferred  Securities and (ii) no later than April 30, 2037. The
Series  A  Debentures  shall  be  issued  in the  form of  registered  Series  A
Debentures without coupons.

                  SECTION  2.02.  The  Series A  Debentures  shall be  issued in
certificated  form and  registered  in the name of the  Property  Trustee or its
nominee,  subject to the exchange of such certificated Series A Debentures for a
Global  Debenture  as  provided  in the  Trust  Agreement.  Series A  Debentures
represented  by a Global  Debenture will not be  exchangeable  for, and will not
otherwise be issuable as, Series A Debentures in  certificated  form,  except as
provided in this First  Supplemental  Indenture.  Principal  and interest on the
Series A  Debentures  will be payable,  the transfer of such Series A Debentures
will be registrable and such Series A Debentures will be exchangeable for Series
A Debentures  bearing  identical terms and provisions at the office or agency of
the Company maintained for that purpose in the Borough of Manhattan, The City of
New York; provided,  however, that payment of interest may be made at the option
of the Company by check mailed to the registered holder at such address as shall
appear in the  Debenture  Register or, with  respect to a  registered  holder of
$1,000,000 or more in aggregate  principal amount of Series A Debentures who has
delivered  a  written  request  to the  Trustee  at least  14 days  prior to the
relevant  Interest  Payment Date (as defined in Section 2.03 below)  electing to
have  payments  made by wire  transfer  to a  designated  account  in the United
States,  by wire  transfer of  immediately  available  funds to such  designated
account. The Company and the Trustee will act as co-paying agents for the Series
A  Debentures.  Payments of principal of and interest on the Series A Debentures
issued as a Global  Debenture  will be made to the  Depositary.  The  Depository
Trust Company (55 Water Street,  New York) will  initially act as the Depositary
for the Global Debenture.

                  A  Global   Debenture  shall  be  exchangeable  for  Series  A
Debentures  registered in the names of persons other than the  Depositary or its
nominee only if (i) the Depositary  notifies the Company that it is unwilling or
unable to continue as a depositary  for such Global  Debenture  and no successor
depositary shall have been appointed, or if at any time the Depositary ceases to
be a clearing agency  registered  under the Securities  Exchange Act of 1934, as
amended, at a time when the Depositary is required to be so registered to act as
such  depositary,  (ii) the Company in its sole discretion  determines that such
Global  Debenture  shall be so  exchangeable  or (iii) the Global  Debenture was
issued  pursuant  to Section  904 of the Trust  Agreement  and there  shall have
occurred  and be  continuing  an Event of Default  with  respect to such  Global
Debenture and the holders of at least a majority of the beneficial  interests in
such Global  Debenture  advise the Trustee in writing that the continuation of a
book-entry  system  through the  Depositary is no longer in their best interest,
then the Trustee shall notify the Depositary and the Depositary shall notify all
holders of  beneficial  interests in the Global  Debenture of the  occurrence of
such event and the  availability  of Series A Debentures  to such  holders.  Any
Global Debenture that is exchangeable  pursuant to the preceding  sentence shall
be  exchangeable  for  definitive  certificates  registered in such names as the
Depositary shall direct.

                  SECTION  2.03.  Each Series A Debenture  will bear interest at
the rate of 8.00% per annum from and  including the original date of issuance or
from the most recent  Interest  Payment Date referred to below to which interest
has been paid or duly provided for until the principal  thereof  becomes due and
payable,  and on any overdue  principal  and (to the extent that payment of such
interest is  enforceable  under  applicable  law) on any overdue  installment of
interest at the same rate per annum,  payable  quarterly in arrears on March 31,
June 30,  September 30 and December 31 of each year (each, an "Interest  Payment
Date"),  commencing  on June 30, 1997, to the person in whose name such Series A
Debenture or any  predecessor  Series A Debenture is  registered at the close of
business on the Business Day next preceding that Interest  Payment Date (each, a
"Record Date"); provided,  however, that if the Series A Debentures shall not be
in the form of a Global Debenture,  the record date shall be the 15th day of the
month in which the relevant  Interest  Payment Date  occurs.  Any such  interest
installment  not  punctually  paid or duly provided for on any Interest  Payment
Date  shall  forthwith  cease to be  payable  to the  registered  holder  on the
relevant  Record Date,  and may be paid to the person in whose name the Series A
Debenture (or one or more predecessor  Debentures) is registered at the close of
business on a special  record date to be fixed by the Trustee for the payment of
such defaulted interest, notice whereof shall be given to the registered holders
of the Series A Debentures  not less than 10 days prior to such  special  record
date,  or may be paid at any time in any other  lawful  manner not  inconsistent
with  the  requirements  of any  securities  exchange  on  which  the  Series  A
Debentures  may be  listed,  and upon  such  notice as may be  required  by such
exchange, all as more fully provided in the Indenture;  provided,  however, that
interest  (other than  interest  described  in the next  sentence)  shall not be
considered payable by the Company on any Interest Payment Date falling within an
Extension  Period,  unless  the  Company  has  elected to make a full or partial
payment of interest  accrued on the Series A Debentures on that Interest Payment
Date. Any partial payment of interest  accrued on the Series A Debentures on any
Interest  Payment Date falling within an Extension Period shall be paid pro rata
to such  registered  holders  based  upon  the  principal  amount  of  Series  A
Debentures then held by such registered holders.

                  The amount of interest payable for any period will be computed
on the basis of a 360-day  year of twelve  30-day  months  and,  for any  period
shorter than a full  calendar  month,  on the basis of the actual number of days
elapsed in such period.  In the event that any date on which interest is payable
on the Series A  Debentures  is not a Business  Day,  then  payment of  interest
payable on such date will be made on the next  succeeding day that is a Business
Day (and  without any  interest or other  payment in respect of any such delay),
except that, if such Business Day is in the next succeeding  calendar year, such
payment shall be made on the  immediately  preceding  Business Day, in each case
with  the  same  force  and  effect  as if made on the  date  such  payment  was
originally payable.


                                  ARTICLE THREE
                      Redemption of the Series A Debentures

                  SECTION  3.01.  Subject to the terms of  Article  Three of the
Indenture,  the Company  shall have the right to redeem the Series A Debentures,
in whole,  at any time,  or in part,  from time to time,  on or after  April 30,
2002, at a redemption  price equal to 100% of the  principal  amount of Series A
Debentures  to be redeemed plus any accrued and unpaid  interest  thereon to the
date of such redemption.  If the Series A Debentures are only partially redeemed
pursuant to this Section,  the Series A Debentures will be redeemed by lot or by
any other method utilized by the Trustee, such method to be determined solely in
the  discretion  of the  Trustee.  The  Company  may not  redeem  the  Series  A
Debentures in part unless all accrued and unpaid  interest has been paid in full
on all outstanding  Series A Debentures for all interest periods  terminating on
or prior to the date of redemption.

                  SECTION 3.02. If a Special Event in respect of the Trust shall
occur and be  continuing,  the Company  may, at its option,  redeem the Series A
Debentures at any time within 90 days of the  occurrence of such Special  Event,
in whole,  but not in part,  subject to the  provisions  of the  Indenture.  The
redemption  price for any Series A Debenture so redeemed  shall be equal to 100%
of the  principal  amount of the Series A  Debentures  to be  redeemed  plus any
accrued and unpaid interest thereon to the date of redemption.


                                  ARTICLE FOUR
                      Extension of Interest Payment Period

                  SECTION  4.01.  Subject to Section 4.06 of the  Indenture  and
Section 5.06 of this First  Supplemental  Indenture,  the Company shall have the
right,  at any time  during  the term of the Series A  Debentures,  to defer the
payment of  interest on such  Series A  Debentures  at any time and from time to
time for a period not to exceed 20 consecutive  calendar  quarters from the last
Interest Payment Date to which interest was paid in full (but in no event beyond
the maturity of the Series A Debentures) (each, an "Extension  Period"),  during
which  periods  the  Company  shall have the right to make  partial  payments of
interest on any Interest  Payment Date, and at the end of such Extension  Period
the Company shall pay all interest then accrued and unpaid thereon. Prior to the
termination  of any such  Extension  Period,  the Company may further extend the
interest  payment period,  provided that such Extension Period together with all
such previous and further  extensions of such Extension  Period shall not exceed
20  consecutive  quarters  or  extend  beyond  the  maturity  of  the  Series  A
Debentures.  No such Extension Period shall end on a date other than an Interest
Payment Date. Upon termination of any such Extension Period and upon the payment
of all accrued and unpaid  interest  then due,  the Company may elect to begin a
new Extension Period,  subject to the above  requirements.  No interest shall be
due and payable during an Extension Period, except at the end thereof.

                  SECTION  4.02.  The  Company  shall give the  Trustee  and the
Administrative  Trustees  written  notice of (i) any  election by the Company to
initiate an Extension Period and the duration thereof,  (ii) any election by the
Company to extend an Extension  Period beyond the Interest Payment Date on which
that  Extension  Period is then  scheduled to terminate and the duration of such
extension  and (iii)  any  election  by the  Company  to make a full or  partial
payment of interest  accrued on the Series A Debentures on any Interest  Payment
Date  during an  Extension  Period and the amount of such  payment.  In no event
shall such  notice by the Company be given less than one  Business  Day prior to
the earlier of (A) the date the  Administrative  Trustees  are  required to give
notice  to The New  York  Stock  Exchange  or other  applicable  self-regulatory
organization or to the holders of the Preferred Securities of the record date or
the date  Distributions  are payable but in any event not less than one Business
Day prior to such  record  date or (B) one  Business  Day prior to such date the
Distributions on the Preferred Securities would have been payable except for the
election to begin such Extension  Period.  Upon receipt of any such notice,  the
Trustee  shall give  written  notice of the  Company's  election  by mail to the
Series A  Debentureholders  within five Business  Days. The Company shall make a
public  announcement  of any such  election  in  accordance  with New York Stock
Exchange rules not less than five Business Days prior to such Record Date.


                                  ARTICLE FIVE

              Additional Terms Relating to the Preferred Securities

                  SECTION  5.01.  (a) For so long  as any  Preferred  Securities
remain  outstanding,  if,  upon an Event of Default,  the  Trustee  fails or the
holders of not less than 33% in aggregate  principal  amount of the  outstanding
Series  A  Debentures  fail to  declare  the  principal  of all of the  Series A
Debentures  to be  immediately  due and payable,  the holders of at least 33% in
aggregate  liquidation  preference of the Preferred  Securities then outstanding
(determined in accordance with the Trust  Agreement)  shall have such right by a
notice in writing to the Company and the Trustee;  and upon any such declaration
such  principal  amount  of and the  accrued  interest  on all of the  Series  A
Debentures shall become  immediately due and payable (subject to Section 6.01(c)
of the  Indenture),  provided that the payment of principal and interest on such
Series A Debentures  shall  remain  subordinated  to the extent  provided in the
Indenture.

                  (b)   For  so  long  as  any   Preferred   Securities   remain
outstanding,  if,  upon an Event of  Default,  the  Trustee  fails to proceed to
enforce any right  available  to the holders of the Series A  Debentures  for 60
days,  the holders of at least 33% in aggregate  liquidation  preference  of the
Preferred  Securities then outstanding  (determined in accordance with the Trust
Agreement)  shall have the right,  to the fullest  extent  permitted  by law, to
directly institute proceedings for enforcement of such rights.

                  (c)   For  so  long  as  any   Preferred   Securities   remain
outstanding,  to the fullest extent  permitted by law, upon the occurrence of an
Event of Default described in Section 6.01(a)(1) or 6.02(a)(2) of the Indenture,
any  holder  of  Preferred  Securities  shall  have  the  right to  institute  a
proceeding  directly  against  the Company  for  enforcement  of payment to such
holder of the  principal  of or  interest  on the Series A  Debentures  having a
principal  amount equal to the aggregate  liquidation  preference of the related
Preferred  Securities  held by such holder after the due date specified for such
payment in the Series A Debentures.

                  SECTION 5.02. For so long as any Preferred  Securities  remain
outstanding,  if the holders of a majority in aggregate  principal amount of the
Series A Debentures fail to waive an Event of Default in accordance with Section
6.06 of the  Indenture,  the  holders of a  majority  in  aggregate  liquidation
preference  of  the  Preferred   Securities  then  outstanding   (determined  in
accordance with the Trust Agreement) have such right.

                  SECTION 5.03. For so long as any Preferred  Securities  remain
outstanding,  the  Company  shall not  consolidate  with or merge into any other
corporation or convey, transfer or lease its properties and assets substantially
as an entirety to any Person, and no Person shall consolidate with or merge into
the Company or convey, transfer or lease its properties and assets substantially
as an entirety to the Company,  unless such consolidation,  merger,  conveyance,
transfer or lease is permitted  under the Trust  Agreement and the Guarantee and
does not give rise to any  breach or  violation  of the Trust  Agreement  or the
Guarantee.

                  SECTION 5.04. For so long as any Preferred  Securities  remain
outstanding,  the  Company  shall  not  terminate  the  Indenture  or  amend  or
supplement  the Indenture in any manner that  materially  adversely  affects the
interests  of the holders of the  Preferred  Securities,  and subject to Section
6.01(c) of the Indenture,  no waiver of any Event of Default or compliance  with
any covenant under the Indenture shall be effective without the prior consent to
such waiver of the holders of at least a majority of the  aggregate  liquidation
preference  of  such  Preferred  Securities  then  outstanding   (determined  in
accordance  with the Trust  Agreement)  unless  and until the  principal  of the
Series A Debentures and all accrued and unpaid  interest  thereon have been paid
in full.

                  SECTION 5.05. In the event that (i) the Trust is the holder of
all of the Outstanding  Series A Debentures,  (ii) a Tax Event in respect of the
Trust shall have occurred and be continuing and (iii) the Company shall not have
(a)  redeemed  the Series A  Debentures  pursuant to Section  3.02 of this First
Supplemental Indenture or (b) terminated the Trust pursuant to Section 902(b) of
the Trust  Agreement,  the  Company  shall pay to the Trust  (and its  permitted
successors  or assigns under the Trust  Agreement)  for so long as the Trust (or
its permitted  successor or assignee) is the  registered  holder of any Series A
Debentures, such additional amounts as may be necessary in order that the amount
of  Distributions  (including  any  Additional  Amounts (as defined in the Trust
Agreement))  then  due  and  payable  by  the  Trust  on the  related  Preferred
Securities  and  Common  Securities  that  at any  time  remain  outstanding  in
accordance  with the  terms  thereof  shall  not be  reduced  as a result of any
Additional  Taxes (the  "Additional  Sums").  Whenever in the  Indenture  or the
Series A  Debentures  there is a  reference  in any  context  to the  payment of
principal  of or  interest on the Series A  Debentures,  such  mention  shall be
deemed to include mention of the payments of the Additional Sums provided for in
this paragraph to the extent that, in such context, Additional Sums are, were or
would be payable in respect thereof pursuant to the provisions of this paragraph
and express  mention of the payment of Additional  Sums (if  applicable)  in any
provisions  hereof shall not be construed as excluding  Additional Sums in those
provisions  hereof where such express  mention is not made,  provided,  however,
that the  deferral of the payment of interest  pursuant to Section  4.01 of this
First  Supplemental  Indenture  or the Series A  Debentures  shall not defer the
payment of any Additional  Sums that may be due and payable during such interest
payment period.

                  SECTION 5.06. For so long as any Preferred  Securities  remain
outstanding,  the  Company  covenants  and agrees  with each  holder of Series A
Debentures  issued to the Trust  that it will not,  and it will not  permit  any
Subsidiary  of the Company  to, (i)  declare,  set aside or pay any  dividend or
distribution on, or repurchase, redeem, or otherwise acquire or make any sinking
fund payment with respect to, any shares of the Company's  capital stock or (ii)
make any  payment  of  principal,  interest  or  premium,  if any,  on or repay,
repurchase or redeem any debt  securities that rank pari passu with or junior in
interest to the Series A Debentures or make any guarantee  payments with respect
to the  foregoing  (other than (a) dividends or  distributions  in shares of its
capital  stock  or in  rights  to  acquire  shares  of its  capital  stock,  (b)
conversions  into or exchanges for shares of its capital stock, (c) redemptions,
purchases  or other  acquisitions  of shares of its  capital  stock made for the
purpose of an employee  incentive  plan or benefit plan of the Company or any of
its subsidiaries and mandatory redemptions or sinking fund payments with respect
to any series of  Preferred  Stock of the Company  that are subject to mandatory
redemption or sinking fund  requirements,  provided  that the  aggregate  stated
value of all such series  outstanding  at the time of any such  payment does not
exceed five percent of the  aggregate of (1) the total  principal  amount of all
bonds or other securities representing secured indebtedness issued or assumed by
the Company and then  outstanding and (2) the capital and surplus of the Company
to be stated on the books of account of the Company  after giving effect to such
payment,  provided,  however,  that any moneys deposited in any sinking fund and
not in violation of this  provision may thereafter be applied to the purchase or
redemption of such Preferred  Stock in accordance with the terms of such sinking
fund without regard to the  restrictions  contained in this  provision,  and (d)
payments  under any guarantee by the Company with respect to any securities of a
subsidiary of the Company,  provided that the proceeds from the issuance of such
securities  were used to purchase  Debentures of any series) if at such time (i)
there shall have  occurred  any event of which the Company has actual  knowledge
that  (a)  with the  giving  of  notice  or the  lapse  of time or  both,  would
constitute an Event of Default hereunder and (b) in respect of which the Company
shall not have taken  reasonable  steps to cure,  (ii) the  Company  shall be in
default with respect to its payment of any  obligations  under the  Guarantee or
(iii) the Company  shall have given notice of its election to begin an Extension
Period as provided  herein and shall not have  rescinded  such  notice,  or such
period, or any extension thereof, shall be continuing.

                  SECTION 5.07. For so long as any Preferred  Securities  remain
outstanding,  the Company also covenants with each holder of Series A Debentures
issued to the Trust (i) to maintain directly or indirectly 100% ownership of the
Common Securities of the Trust; provided,  however, that any permitted successor
of the Company under the  Indenture  may succeed to the  Company's  ownership of
such Common Securities, (ii) not to voluntarily terminate,  wind-up or liquidate
the  Trust,  except  (a) in  connection  with a  distribution  of the  Series  A
Debentures to the holders of Preferred Securities in liquidation of the Trust or
(b)  in  connection  with  certain  mergers,   consolidations  or  amalgamations
permitted  by the  Trust  Agreement  and  (iii) to use its  reasonable  efforts,
consistent  with the terms and provisions of the Trust  Agreement,  to cause the
Trust to remain  classified as a "grantor  trust" and not to be classified as an
association  taxable as a  corporation  for  United  States  federal  income tax
purposes.


                                   ARTICLE SIX
                           Form of Series A Debenture

                  The  Series A  Debentures  and the  Trustee's  Certificate  of
Authentication  to be endorsed  thereon are to be substantially in the following
forms:

                           (FORM OF FACE OF DEBENTURE)

                  [If the  Debenture  is to be  issued  as a  Global  Debenture,
insert--This Debenture is a Global Debenture within the meaning of the Indenture
hereinafter  referred  to and is  registered  in the name of a  Depositary  or a
nominee  of  a  Depositary.   This  Debenture  is  exchangeable  for  Debentures
registered in the name of a person other than the Depositary or its nominee only
in the limited circumstances described in the Indenture, and no transfer of this
Debenture  (other than a transfer of this Debenture as a whole by the Depositary
to a  nominee  of  the  Depositary  or by a  nominee  of the  Depositary  to the
Depositary or another nominee of the Depositary, or to a successor Depositary or
to a nominee of such successor  Depositary) may be registered  except in limited
circumstances.

                  Unless  this   Debenture  is   presented   by  an   authorized
representative  of The Depository  Trust Company (55 Water Street,  New York) to
the issuer or its agent for registration of transfer,  exchange or payment,  and
any Debenture  issued is registered in the name of Cede & Co. or such other name
as requested by an authorized representative of The Depository Trust Company and
any  payment  hereon is made to Cede & Co.,  ANY  TRANSFER,  PLEDGE OR OTHER USE
HEREOF FOR VALUE OR OTHERWISE BY A PERSON IS WRONGFUL inasmuch as the registered
owner hereof, Cede & Co., has an interest herein.]


No.___________                                                       $__________


                         CENTRAL POWER AND LIGHT COMPANY

                                      8.00%
               JUNIOR SUBORDINATED DEFERRABLE INTEREST DEBENTURE,
                                    SERIES A

                  CENTRAL POWER AND LIGHT COMPANY,  a corporation duly organized
and  existing  under the laws of the State of Texas  (herein  referred to as the
"Company",  which term includes any successor  corporation under the Indenture),
for  value  received,   hereby  promises  to  pay  to  _____________________  or
registered assigns, the principal sum of $154,639,200,  on April 30, 2037, or on
such earlier date as the Company may elect  subject to the terms of Section 2.01
of the First  Supplemental  Indenture and to pay interest on such  principal sum
from and  including May 14, 1997 or from the most recent  interest  payment date
(each such date, an "Interest  Payment Date") to which interest has been paid or
duly provided for, payable  quarterly in arrears on March 31, June 30, September
30 and December 31 of each year,  commencing  on June 30,  1997,  at the rate of
8.00% per annum,  until the principal  hereof shall have become due and payable,
and on any  overdue  principal  and  premium,  if any,  and (to the extent  that
payment of such interest is  enforceable  under  applicable  law) on any overdue
installment  of  interest  at the same rate per annum.  The  amount of  interest
payable on any Interest Payment Date shall be computed on the basis of a 360-day
year of twelve  30-day  months and, for any period  shorter than a full calendar
month, on the basis of the actual number of days elapsed in such period.  In the
event that any date on which  interest  is payable  on this  Debenture  is not a
Business Day, then payment of interest  payable on such date will be made on the
next  succeeding  day which is a Business Day (and without any interest or other
payment in respect of any such delay),  except that,  if such Business Day is in
the next succeeding calendar year, such payment shall be made on the immediately
preceding  Business  Day, in each case with the same force and effect as if made
on such date. The interest  installment so payable,  and punctually paid or duly
provided for on any Interest Payment Date will, as provided in the Indenture, be
paid to the  person in whose  name this  Debenture  (or one or more  Predecessor
Debentures,  as defined in the Indenture) is registered at the close of business
on the Business Day next  preceding  that Interest  Payment Date (each a "Record
Date"); provided,  however, that if this Debenture shall not be in the form of a
Global Debenture the record date shall be the 15th day of the month in which the
relevant  Interest  Payment  Date  occurs.  Any such  interest  installment  not
punctually  paid  or  duly  provided  for on any  Interest  Payment  Date  shall
forthwith  cease to be payable to the registered  holder on the relevant  Record
Date, and may be paid to the person in whose name this Debenture (or one or more
Predecessor  Debentures)  is  registered  at the close of  business on a special
record  date to be  fixed  by the  Trustee  for the  payment  of such  defaulted
interest, notice whereof shall be given to the registered holders of this series
of Debentures not less than 10 days prior to such special record date, or may be
paid  at any  time  in  any  other  lawful  manner  not  inconsistent  with  the
requirements  of any  securities  exchange on which the  Debentures  may then be
listed,  and upon such notice as may be required by such  exchange,  all as more
fully provided in the Indenture hereinafter referred to; provided, however, that
interest shall not be considered  payable by the Company on any Interest Payment
Date falling within an Extension  Period (as defined below),  unless the Company
has  elected  to make a full or  partial  payment  of  interest  accrued on this
Debenture on that Interest Payment Date. Any partial payment of interest accrued
on this series of  Debentures  on any Interest  Payment  Date falling  within an
Extension  Period  shall  be paid  pro  rata to the  registered  holder  of this
Debenture  based upon the principal  amount of this Debenture in relation to the
aggregate  principal  amount of all Debentures of this series then  outstanding.
The principal of (and premium,  if any) and the interest on this Debenture shall
be payable at the office or agency of the Company maintained for that purpose in
the Borough of  Manhattan,  The City of New York, in any coin or currency of the
United  States of  America  which at the time of  payment  is legal  tender  for
payment of public and private debts; provided, however, that payment of interest
may be made at the  option of the  Company  by check  mailed  to the  registered
holder at such  address  as shall  appear in the  Debenture  Register  or,  with
respect to a registered  holder of  $1,000,000  or more in  aggregate  principal
amount of Debentures who has delivered a written request to the Trustee at least
14 days prior to the relevant  Interest  Payment Date  electing to have payments
made by wire  transfer to a  designated  account in the United  States,  by wire
transfer of immediately available funds to such designated account.

                  The indebtedness evidenced by this Debenture is, to the extent
provided in the  Indenture,  subordinated  and junior in right of payment to the
prior payment in full of all Senior  Indebtedness,  and this Debenture is issued
subject to the provisions of the Indenture with respect thereto.  Each holder of
this Debenture,  by accepting the same, (a) agrees to and shall be bound by such
provisions,  (b)  authorizes  and directs the Trustee on its behalf to take such
action as may be necessary or  appropriate  to  acknowledge  or  effectuate  the
subordination so provided and (c) appoints the Trustee its  attorney-in-fact for
any and all such purposes.  Each holder hereof, by its acceptance hereof, hereby
waives all notice of the acceptance of the  subordination  provisions  contained
herein and in the Indenture by each holder of Senior  Indebtedness,  whether now
outstanding or hereafter incurred,  and waives reliance by each such holder upon
those provisions.

                  This Debenture  shall not be entitled to any benefit under the
Indenture hereinafter referred to, be valid or become obligatory for any purpose
until the Certificate of  Authentication  hereon shall have been signed by or on
behalf of the Trustee.

                  The  provisions of this Debenture are contained on the reverse
side hereof and such continued  provisions  shall for all purposes have the same
effect as though fully set forth at this place.



<PAGE>


                  IN WITNESS WHEREOF,  the Company has caused this Instrument to
be executed.

                                                 CENTRAL POWER AND LIGHT COMPANY



                                                 By
                                                    Wendy G. Hargus, Treasurer

Attest:




Marilyn Kirkland, Secretary


                          CERTIFICATE OF AUTHENTICATION

                  This is one of the  Debentures  of the  series  of  Debentures
described in the within-mentioned Indenture.

Dated:


THE BANK OF NEW YORK
as Trustee or as Authenticating Agent



By
   Authorized Signatory


<PAGE>



                                    (REVERSE)

            8.00% JUNIOR SUBORDINATED DEFERRABLE INTEREST DEBENTURE,
                                    SERIES A
                                   (continued)

                  This  Debenture  is  one  of  a  duly  authorized   series  of
debentures of the Company (herein  sometimes  referred to as the  "Debentures"),
specified in the Indenture (as defined below), all issued or to be issued in one
or more series under and  pursuant to an Indenture  dated as of May 1, 1997 duly
executed and delivered  between the Company and THE BANK OF NEW YORK, a New York
banking  corporation,  as Trustee  (herein  referred  to as the  "Trustee"),  as
supplemented by the First Supplemental Indenture dated as of May 1, 1997 between
the Company and the Trustee (such Indenture as so supplemented being hereinafter
referred  to  as  the  "Indenture"),  to  which  Indenture  and  all  indentures
supplemental  thereto  reference is hereby made for a description of the rights,
limitations  of rights,  obligations,  duties and  immunities  thereunder of the
Trustee,  the  Company and the  holders of the  Debentures.  By the terms of the
Indenture,  the  Debentures  are issuable in series which may vary as to amount,
date of  maturity,  rate of interest and in other  respects as in the  Indenture
provided.  This series of Debentures is limited in aggregate principal amount as
specified in the First Supplemental Indenture.

                  Subject to the terms of Article  Three of the  Indenture,  the
Company  shall have the right to redeem  the  Debentures  of this  series at the
option of the Company,  without  premium or penalty,  in whole or in part at any
time  and  from  time  to  time  on  or  after  April  30,  2002  (an  "Optional
Redemption"), at a redemption price equal to 100% of the principal amount of the
Debentures  of this series to be redeemed  plus any accrued and unpaid  interest
thereon to the date of such  redemption.  If the  Debentures  of this series are
only partially redeemed by the Company pursuant to an Optional  Redemption,  the
Debentures  of  this  series  will be  redeemed  by lot or by any  other  method
utilized by the Trustee,  such method to be determined  solely in the discretion
of the Trustee.

                  If a Special  Event in respect of the Trust shall occur and be
continuing,  the Company may, at its option,  redeem this  Debenture at any time
within 90 days of the  occurrence of such Special  Event,  in whole,  but not in
part,  subject to the provisions of the Indenture.  The redemption price for any
Debenture  of this  series so redeemed  shall be equal to 100% of the  principal
amount thereof plus accrued and unpaid interest to the date of such redemption.

                  In the event of redemption  of this  Debenture in part only, a
new  Debenture or Debentures of this series for the  unredeemed  portion  hereof
will be issued in the name of the holder hereof upon the cancellation hereof.

                  In case an Event of Default with respect to the  Debentures of
this series shall have occurred and be  continuing,  the principal of all of the
Debentures  of this  series may be  declared,  and upon such  declaration  shall
become,  due and  payable,  in the  manner,  with the effect and  subject to the
conditions provided in the Indenture.

                  The Indenture  contains  provisions for defeasance at any time
of the entire  indebtedness  of the Debentures of this series upon compliance by
the Company with certain conditions set forth therein.

                  The Indenture contains  provisions  permitting the Company and
the  Trustee,  with the  consent of the  holders of not less than a majority  in
aggregate principal amount of the Debentures of each series affected at the time
Outstanding, as defined in the Indenture, to execute supplemental indentures for
the purpose of adding any provisions  to,  changing in any manner or eliminating
any of the  provisions of the Indenture or of any  supplemental  indenture or of
modifying in any manner the rights of the holders of the  Debentures;  provided,
however, that no such supplemental indenture shall (i) extend the fixed maturity
of any Debentures of any series, reduce the principal amount thereof, reduce the
rate or extend  the time of payment of  interest  thereon or reduce any  premium
payable upon the redemption  thereof,  without the consent of the holder of each
Debenture so affected or (ii) reduce the aforesaid percentage of Debentures, the
holders of which are  required  to consent to any such  supplemental  indenture,
without  the  consent of the  holders of each  Debenture  then  outstanding  and
affected thereby. The Indenture also contains provisions  permitting the holders
of a majority in aggregate  principal  amount of the Debentures of all series at
the  time  outstanding  affected  thereby,  on  behalf  of  the  holders  of the
Debentures of such series,  to waive any past default in the  performance of any
of the covenants  contained in the  Indenture,  or  established  pursuant to the
Indenture with respect to such series, and its consequences, except a default in
the payment of the  principal  of or premium,  if any, or interest on any of the
Debentures of such series,  which default may be waived by the unanimous consent
of the holders  affected.  A default may also be deemed to be waived  subject to
the Company's compliance with certain provisions of the Indenture, including the
payment  of  matured  interest  and  principal,  other  than  principal  on  the
Debentures  that  has  not  become  due by  their  terms,  and  the  remedy  or,
alternatively,  waiver  of all other  defaults  under  the  Indenture.  Any such
consent or waiver by the registered  holder of this Debenture (unless revoked as
provided in the Indenture)  shall be conclusive and binding upon such holder and
upon all future holders and owners of this Debenture and of any Debenture issued
in exchange  herefor or in place hereof  (whether by registration of transfer or
otherwise),  irrespective  of whether  or not any  notation  of such  consent or
waiver is made upon this Debenture.

                  For so long as any Preferred  Securities  remain  outstanding,
if, upon an Event of Default,  the Trustee fails or the holders of not less than
33% in principal  amount of the  outstanding  Debentures  of this series fail to
declare the principal of all of the  Debentures of this series to be immediately
due and payable, the holders of at least 33% in aggregate liquidation preference
of the Preferred Securities then outstanding  (determined in accordance with the
related  Trust  Agreement)  shall  have such right by a notice in writing to the
Company and the Trustee;  and upon any such declaration such principal amount of
and the accrued  interest on all of the  Debentures  of this series shall become
immediately  due and  payable  (subject  to Section  6.01(c) of the  Indenture),
provided  that the payment of principal  and interest on such  Debentures  shall
remain subordinated to the extent provided in the Indenture.

                  For so long as any Preferred  Securities  remain  outstanding,
if, upon an Event of Default,  the Trustee fails to proceed to enforce any right
available to the holders of the Series A Debentures  for 60 days, the holders of
at least 33% in aggregate  liquidation  preference of the  Preferred  Securities
then outstanding  (determined in accordance with the Trust Agreement) shall have
the right,  to the  fullest  extent  permitted  by law,  to  directly  institute
proceedings for enforcement of such rights.

                  For so long as any Preferred Securities remain outstanding, to
the fullest extent  permitted by law, upon the occurrence of an Event of Default
described in Section  6.01(a)(1) or 6.02(a)(2) of the  Indenture,  any holder of
Preferred  Securities  shall have the right to institute a  proceeding  directly
against the Company for  enforcement  of payment to such holder of the principal
of or interest on the Series A Debentures having a principal amount equal to the
aggregate  liquidation  preference of the related  Preferred  Securities held by
such  holder  after the due date  specified  for such  payment  in the  Series A
Debentures.

                  No reference  herein to the Indenture and no provision of this
Debenture  or of the  Indenture  shall  alter or impair  the  obligation  of the
Company,  which is  absolute  and  unconditional,  to pay the  principal  of and
premium, if any, and interest on this Debenture at the time and place and at the
rate and in the money herein prescribed.

                  Subject to the provisions of the Indenture,  the Company shall
have the right,  at any time  during the term of this series of  Debentures,  to
defer the payment of interest on this series of  Debentures at any time and from
time to time for a period not to exceed 20  consecutive  calendar  quarters from
the last  Interest  Payment  Date to which  interest was paid in full (but in no
event  beyond the  maturity of the Series A  Debentures)  (each,  an  "Extension
Period")  during which  periods the Company shall have the right to make partial
payments  of  interest  on any  Interest  Payment  Date,  and at the end of such
Extension  Period the Company  shall pay all  interest  then  accrued and unpaid
thereon.  Prior to the termination of any such Extension Period, the Company may
further extend the interest payment period,  provided that such Extension Period
together with all such previous and further  extensions of such Extension Period
shall not exceed 20  consecutive  quarters or extend  beyond the maturity of the
Series A Debentures.  Upon termination of any such Extension Period and upon the
payment of all accrued and unpaid  interest  then due,  the Company may select a
new Extension Period,  subject to the above  requirements.  No interest shall be
due and payable during an Extension Period, except at the end thereof.

                  As   provided  in  the   Indenture   and  subject  to  certain
limitations  therein set forth, this Debenture is transferable by the registered
holder hereof on the Debenture  Register of the Company,  upon surrender of this
Debenture  for  registration  of transfer at the office or agency of the Company
designated  for such purpose in the Borough of Manhattan,  The City of New York,
accompanied  by  a  written  instrument  or  instruments  of  transfer  in  form
satisfactory  to the  Company and the Trustee  duly  executed by the  registered
holder hereof or its attorney duly  authorized in writing,  and thereupon one or
more new  Debentures  of  authorized  denominations  and for the same  aggregate
principal  amount  and series  will be issued to the  designated  transferee  or
transferees.  No  service  charge  will be made for any such  transfer,  but the
Company  may  require  payment  of a sum  sufficient  to cover  any tax or other
governmental charge payable in relation thereto.

                  Prior to due presentment for  registration of transfer of this
Debenture,  the  Company,  the  Trustee,  any  paying  agent  and any  Debenture
Registrar may deem and treat the registered  holder hereof as the absolute owner
hereof (whether or not this Debenture shall be overdue and  notwithstanding  any
notice of  ownership or writing  hereon made by anyone other than the  Debenture
Registrar)  for  the  purpose  of  receiving  payment  of or on  account  of the
principal hereof and premium,  if any, and interest due hereon and for all other
purposes,  and neither the Company nor the Trustee nor any paying  agent nor any
Debenture Registrar shall be affected by any notice to the contrary.

                  No recourse  shall be had for the payment of the  principal of
or the interest on this Debenture,  or for any claim based hereon,  or otherwise
in  respect  hereof,  or based on or in respect of the  Indenture,  against  any
incorporator,  stockholder,  officer or director,  past,  present or future,  as
such, of the Company or of any predecessor or successor corporation,  whether by
virtue of any constitution, statute or rule of law, or by the enforcement of any
assessment or penalty or otherwise,  all such liability being, by the acceptance
hereof  and as part of the  consideration  for the  issuance  hereof,  expressly
waived and released.

                  [If the  Debenture  is to be  issued  as a  Global  Debenture,
insert--This  Global  Debenture is  exchangeable  for Debentures in certificated
form only under certain limited  circumstances  set forth in the Indenture.] The
Debentures  of this series are issuable in  registered  form without  coupons in
denominations  of $25 and any  integral  multiple  thereof.  As  provided in the
Indenture  and  subject to certain  limitations  herein and  therein  set forth,
Debentures  of this  series  so issued  are  exchangeable  for a like  aggregate
principal  amount  of  Debentures  of  this  series  of a  different  authorized
denomination, as requested by the holder surrendering the same.

                  All terms  used in this  Debenture  which are  defined  in the
Indenture shall have the meanings assigned to them in the Indenture.


                                  ARTICLE SEVEN
                      Original Issue of Series A Debentures

                  Series A  Debentures  in the  aggregate  principal  amount  of
$154,639,200 may, upon execution of this First Supplemental  Indenture,  or from
time to time thereafter, be executed by the Company and delivered to the Trustee
for  authentication,  and the Trustee shall thereupon  authenticate  and deliver
such  Debentures  to or upon the  written  order of the  Company,  signed by its
Chairman,  President,  Treasurer or an Assistant Treasurer,  without any further
action by the Company.


                                  ARTICLE EIGHT
                            Miscellaneous Provisions

                  SECTION 8.01. Except as otherwise  expressly  provided in this
First  Supplemental  Indenture or in the form of Series A Debenture or otherwise
clearly  required by the context hereof or thereof,  all terms used herein or in
the form of Series A Debenture that are defined in the Indenture  shall have the
several meanings respectively assigned to them thereby.

                  SECTION 8.02. The  Indenture,  as  supplemented  by this First
Supplemental  Indenture,  is in all respects  ratified and  confirmed,  and this
First Supplemental Indenture shall be deemed part of the Indenture in the manner
and to the extent herein and therein provided.

                  SECTION 8.03.  The recitals  herein  contained are made by the
Company and not by the Trustee,  and the Trustee assumes no  responsibility  for
the correctness  thereof. The Trustee makes no representation as to the validity
or sufficiency of this First Supplemental Indenture.

                  SECTION  8.04.  This  First  Supplemental   Indenture  may  be
executed in any number of counterparts,  each of which shall be an original; but
such counterparts shall together constitute but one and the same instrument.


<PAGE>


                  IN WITNESS WHEREOF,  the parties hereto have caused this First
Supplemental Indenture to be duly executed on the date or dates indicated in the
acknowledgments and as of the day and year first above written.

                                    CENTRAL POWER AND LIGHT COMPANY


                                    By:
                                       Wendy G. Hargus, Treasurer



                                    THE BANK OF NEW YORK, as Trustee



                                    By:
                                       Its: