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                               UNITED STATES
                    SECURITIES AND EXCHANGE COMMISSION
                          Washington, D.C.  20549
                                     
                                     
                               SCHEDULE 13G
                                     
                                     
                 Under the Securities Exchange Act of 1934
            (Amendment No.        9                         )*
                                     
                  American Power Conversion Corporation
                             (Name of Issuer)
                                     
                  Common Stock, $.01 par value per share
                      (Title of Class of Securities)
                                     
                               029066 10 7
                              (CUSIP Number)


     *The  remainder  of this cover page shall be  filled  out  for  a
     reporting  person's initial filing on this form with  respect  to
     the subject class of securities, and for any subsequent amendment
     containing information which would alter the disclosures provided
     in a prior cover page.
     
     The  information  required in the remainder of  this  cover  page
     shall  not be deemed to be "filed" for the purpose of Section  18
     of  the  Securities  Exchange Act of 1934  ("Act")  or  otherwise
     subject  to the liabilities of that section of the Act but  shall
     be  subject to all other provisions of the Act (however, see  the
     Notes).
                         
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1  NAME OF REPORTING PERSON
   S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
   Rodger B. Dowdell, Jr.
   ###-##-####
   
   
2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
                                                  (a)
                                                  (b)
   
3  SEC USE ONLY
   
4  CITIZENSHIP OR PLACE OF ORGANIZATION
   
   United States
   
             5  SOLE VOTING POWER
                
                9,655,225
 NUMBER OF
  SHARES     6  SHARED VOTING POWER
BENEFICIALLY     
                -0-
 OWNED BY
   EACH      7  SOLE DISPOSITIVE POWER
 REPORTING      
  PERSON        9,279,512
   WITH      8  SHARED DISPOSITIVE POWER
                
                375,713

9  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
   
   9,655,225
   
10 CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* [X]
  
   See Item 4

11 PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
  
   10.1%
   
12 TYPE OF REPORTING PERSON *
 
   IN
   
                                                     
                   *SEE INSTRUCTIONS BEFORE FILLING OUT!

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Item 1(a).     Name of Issuer:  American Power Conversion Corporation.

Item 1(b).     Address of Issuer's Principal Executive Offices:
               P.O. Box 278, 132 Fairgrounds Road, West Kingston,
               Rhode Island  02892.

Item 2(a).     Name of Person Filing:  Rodger B. Dowdell, Jr.

Item 2(b).     Address of Principal Business Office or, if None, Residence:
          The address of the principal business office of Mr.
          Dowdell is:  P.O. Box 278, 132 Fairgrounds Road, West
          Kingston, Rhode Island 02892.

Item 2(c).     Citizenship:  Mr. Dowdell is a United States citizen.

Item 2(d).     Title of Class of Securities:  Common Stock, $.01
               par value per share.

Item 2(e).     CUSIP Number:  029066-10-7

Item 3.   If this statement is filed pursuant to Rule 13d-1(b),
          or 13d-2(b), check whether the person filing is a:

                    (a) [     ]    Broker or Dealer registered
                    under Section 15 of the Securities Exchange
                    Act of 1934 (the "Act").

                    (b) [     ]    Bank as defined in
                    Section 3(a)(6) of the Act.

                    (c) [     ]    Insurance Company as defined
                    in Section 3(a)(19) of the Act.

                    (d) [     ]    Investment Company registered
                    under Section 8 of the Investment Company Act
                    of 1940.

                    (e) [     ]    Investment Advisor registered
                    under Section 203 of the Investment Advisers
                    Act of 1940.

                    (f) [     ]    Employee Benefit Plan, Pension
                    Fund which is subject to the provisions of
                    the Employee Retirement Income Security Act
                    of 1974 or Endowment Fund; see
                    Rule 13d-1(b)(1)(ii)(F) of the Act.

                    (g) [     ]    Parent Holding Company, in
                    accordance with Rule 13d-1(b)(ii)(G) of the
                    Act.

                    (h) [     ]    Group, in accordance with
                    Rule 13d-1(b)(1)(ii)(H) of the Act.

                    Not Applicable.

Item 4.        Ownership.

           (a) Amount Beneficially Owned:  Mr. Dowdell may be
               deemed to own beneficially 9,655,225 shares of
               Common Stock as of December 31, 1997, which
               includes 375,713 shares currently allocated to him
               under the Company's Employee Stock Ownership Plan
               ("ESOP").  In addition, Mr. Dowdell is a co-
               trustee of the ESOP, and as such may be deemed to
               be the beneficial owner of the 4,937,226 shares
               currently held by the ESOP.  Mr. Dowdell disclaims
               beneficial ownership to those 4,937,226 shares
               other than the 375,713 shares allocated to him.*

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           (b) Percent of Class:  10.1% (based on the 95,199,000
               shares of Common Stock reported to be outstanding
               on November 6, 1997 in the Quarterly Report on
               Form 10-Q of American Power Conversion Corporation
               for the quarter ended September 28, 1997).

          (c)  Number of shares as to which such person has:

               (i)  sole power to vote or to direct the vote:
                    9,655,225 shares

               (ii) shared power to vote or to direct the vote:
                    0 shares

               (iii)     sole power to dispose or direct the disposition of:
                    9,279,512 shares

               (iv) shared power to dispose or to direct the disposition of:
                    375,713 shares

     *  Information as to ESOP numbers contained herein do not
        reflect final adjustments or allocations for fiscal year ended
        1997.

Item 5.   Ownership of Five Percent or Less of a Class.

          Not Applicable.

Item 6.   Ownership of More than Five Percent on Behalf of Another Person.

          Not Applicable.

Item 7.   Identification and Classification of the Subsidiary
          which Acquired the Security Being Reported on by the
          Parent Holding Company.

          Not Applicable.

Item 8.   Identification and Classification of Members of the
          Group.

          Not Applicable.

Item 9.   Notice of Dissolution of Group.

          Not Applicable.

Item 10.  Certification.

          Not Applicable.  This statement on Schedule 13G is not
          filed pursuant to Rule 13d-1(b).

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                           SIGNATURES


     After reasonable inquiry and to the best of my knowledge and
belief, I certify that the information set forth in this
statement is true, complete and correct.

Date:     February 13, 1998



                                    /s/ Rodger B. Dowdell, Jr.
                                   ______________________________
                                   Rodger B. Dowdell, Jr.


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