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Exhibit 4.6


                                 FLEET BANK - NH
                  SECOND AMENDMENT TO COMMERCIAL LOAN AGREEMENT
                               AND LOAN DOCUMENTS


      THIS SECOND AMENDMENT (the "Amendment") made as of the 12th day of July,
1996, is by and among FLEET BANK - NH, a bank organized under the laws of the
State of New Hampshire with an address of Mail Stop NHNA E02A, 1155 Elm Street,
Manchester, New Hampshire 03101 (the "Bank"), and WPI GROUP, INC., WPI
ELECTRONICS, INC., WPI MAGNETEC, INC., WPI MICRO PALM, INC., WPI POWER SYSTEMS,
INC., WPI TERMIFLEX, INC., WPI MICRO PROCESSOR SYSTEMS, INC., and WPI
DECISIONKEY, INC., each a New Hampshire corporation with a principal office at
1155 Elm Street Manchester, New Hampshire 03101 (all of such corporations are
hereinafter referred to individually and collectively as the "BORROWER").


                               R E C I T A L S:
                               ---------------- 
                            
      WHEREAS, pursuant to a Commercial Loan Agreement dated October 24, 1995,
as amended by First Amendment to Commercial Loan Agreement and Loan Documents
dated March 20, 1996 (as amended, the "Loan Agreement") and certain Loan
Documents as defined therein, the Bank has extended to WPI GROUP, INC., WPI
ELECTRONICS, INC., WPI MAGNETEC, INC., WPI MICRO PALM, INC., WPI POWER SYSTEMS,
INC., WPI TERMIFLEX, INC. WPI MICRO PROCESSOR SYSTEMS, INC., and WPI
DECISIONKEY, INC., a revolving line of credit loan in the principal amount of up
to Twenty Million Dollars ($20,000,000.00) (the "Revolving Line of Credit
Loan");

      WHEREAS, WPI GROUP, INC., owns all of the outstanding capital stock of
each of WPI ELECTRONICS, INC., WPI MAGNETEC, INC., WPI MICRO PALM, INC., WPI
POWER SYSTEMS, INC., WPI TERMIFLEX, INC., and WPI MICRO PROCESSOR SYSTEMS, INC.,
and WPI MICRO PROCESSOR SYSTEMS owns all of the capital stock of WPI
DECISIONKEY, INC.;

      WHEREAS, WPI GROUP, INC. and WPI TERMIFLEX, INC, will form, and own all
of the ownership interest of, WPI GROUP UNITED KINGDOM UNLIMITED, an
unlimited company organized under the laws of the United Kingdom ("WPI-UK");

      WHEREAS, WPI-UK is to acquire all of the capital stock of OYSTER TERMINALS
LIMITED, a corporation organized under the laws of the United Kingdom ("OTL");
and

      WHEREAS, the Borrower has requested, and the Bank has agreed, to (A)
provide for the joinder of each of OTL and WPI-UK as a borrower under the Loan
Agreement and Loan Documents after the acquisition; and (B) increase the maximum
principal amount available to the 




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Borrower under the Revolving Line of Credit Loan to up to Thirty Million Dollars
($30,000,000.00), all upon and subject to the terms and conditions of the Loan
Agreement and the Loan Documents, as the same are amended hereby, and, in
connection therewith, to amend the Loan Agreement and Loan Documents in certain
other respects. Capitalized terms not otherwise defined herein shall have the
meanings ascribed to them in the Loan Agreement.

      NOW, THEREFORE, in consideration of the foregoing premises and the mutual
covenants, agreements and promises contained herein, the parties hereby agree as
follows:

      1. ADDITION OF OTL AND WPI-UK AS BORROWER. Borrower hereby agrees that
after the acquisition of OTL, each of the Loan Agreement and the Loan Documents
shall be amended to join and include each of OTL and WPI-UK, jointly and
severally, as a borrower thereunder, such that each reference to "Borrower" in
the Loan Agreement and in each of the Loan Documents shall mean and include each
of WPI GROUP, INC., WPI ELECTRONICS, INC., WPI MAGNETEC, INC., WPI MICRO PALM,
INC., WPI POWER SYSTEMS, INC., WPI TERMIFLEX, INC., WPI MICRO PROCESSOR SYSTEMS,
INC., WPI DECISIONKEY, INC., WPI-UK and OTL, jointly and severally. Borrower
agrees to take all such actions and to execute all such documents and
instruments as are necessary, proper, or required to effect the provisions of
this Section 2.

      2. Amendment of Loan Agreement.
         ----------------------------

      A.  Section I. A. of the Loan Agreement shall be and hereby is amended
by deleting the same and inserting in place thereof the following:

      A. MAXIMUM AVAILABLE AMOUNT. THE AGGREGATE MAXIMUM AMOUNT AVAILABLE TO
      THE BORROWER UNDER THE REVOLVING LINE OF CREDIT LOAN SHALL BE (i) UP TO
      THIRTY MILLION DOLLARS ($30,000,000.00) THROUGH AND UNTIL THE SOONER OF
      (a) THE DATE UPON WHICH THE BORROWER RECEIVES FINAL PAYMENT OF INSURANCE
      PROCEEDS FOR PROPERTY CASUALTY LOSSES TO ITS FACILITIES IN WARNER, NEW
      HAMPSHIRE,(b) THE DATE UPON WHICH THE AGGREGATE AMOUNT OF INSURANCE
      PROCEEDS RECEIVED BY BORROWER FOR PROPERTY CASUALTY LOSSES TO ITS
      FACILITIES IN WARNER, NEW HAMPSHIRE EXCEEDS THREE MILLION DOLLARS
      ($3,000,000.00), OR (c) DECEMBER 31, 1996; AND (ii) THEREAFTER, UP TO
      TWENTY-SEVEN MILLION FIVE HUNDRED THOUSAND DOLLARS ($27,500,000.00)
      THROUGH JUNE 30, 1997; AND (iii) THEREAFTER, UP TO TWENTY-FIVE MILLION
      DOLLARS ($25,000,000.00) THROUGH THE NEXT REVIEW DATE."

     B. The Loan Agreement shall be and hereby is amended by inserting therein 
the following new negative covenant as Section VI. I. thereof:

      "I. COVENANT TO THIRD PARTIES REGARDING LIENS AND MORTGAGES. PROVIDE ANY
      COVENANT TO, OR ENTER INTO ANY AGREEMENT WITH, ANY THIRD PARTY IDENTICAL
      TO, SUBSTANTIALLY SIMILAR TO, OR OF THE GENERAL NATURE OF THE COVENANT 
      PROVIDED BY THE BORROWER TO THE BANK IN SECTION VI. C. OF THIS AGREEMENT 
      HEREINABOVE."


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      C.  Section II of Schedule A of the Loan Agreement shall be and hereby is
amended by inserting the following new paragraph D:

      "D. LETTERS TO MANAGEMENT ISSUED TO BORROWER BY ITS INDEPENDENT CERTIFIED
      PUBLIC ACCOUNTING FIRM IN CONNECTION WITH ITS AUDIT OF THE BORROWER FOR
      THE 1994 FISCAL YEAR AND FOR EACH FISCAL YEAR THEREAFTER WITH RESPECT TO
      WHICH ANY SUCH LETTERS ARE ISSUED, AS AND WHEN SUCH LETTERS ARE RECEIVED
      BY THE BORROWER."

      D. Section III of Schedule A of the Loan Agreement shall be and hereby is
amended by deleting paragraph A thereof and inserting the following new
paragraph A:

      "A. BORROWER SHALL HAVE ON A CONSOLIDATED BASIS A NET WORTH (AS
      HEREINAFTER DEFINED) EQUAL TO AT LEAST EIGHTEEN MILLION DOLLARS
      ($18,000,000.00) AS AT SEPTEMBER 30, 1996 AND AT ALL TIMES THEREAFTER
      THROUGH SEPTEMBER 29, 1997 AND EQUAL TO LEAST TWENTY-ONE MILLION DOLLARS
      ($21,000,000.00) AS AT SEPTEMBER 30, 1997 AND AT ALL TIMES THEREAFTER.
      "NET WORTH " MEANS TOTAL ASSETS MINUS TOTAL LIABILITIES, ALL AS DETERMINED
      IN ACCORDANCE WITH GENERALLY ACCEPTED ACCOUNTING PRINCIPLES FROM
      BORROWER'S FINANCIAL STATEMENTS DELIVERED TO THE BANK IN ACCORDANCE WITH
      THE COVENANTS OF BORROWER HEREINABOVE (THE "FINANCIAL STATEMENTS")".

      E. Section III of Schedule A of the Loan Agreement shall be and hereby is
amended by deleting paragraph B thereof and inserting the following new
paragraph B:

      "B. BORROWER SHALL HAVE ON A CONSOLIDATED BASIS A RATIO OF FUNDED DEBT (AS
      HEREINAFTER DEFINED) TO EBITDA (AS HEREINAFTER DEFINED) OF NOT GREATER
      THAN (i) 3.5:1 AS AT SEPTEMBER 30, 1996 AND DECEMBER 31, 1996; (ii) 3:1 AS
      AT MARCH 31, 1997 AND JUNE 30, 1997; AND (ii) 2.5:1 AS AT SEPTEMBER 30,
      1997 AND AS AT EACH FISCAL QUARTER END THEREAFTER. "FUNDED DEBT " MEANS
      THE AGGREGATE INTEREST BEARING INDEBTEDNESS OF THE BORROWER AS OF THE
      APPLICABLE DATE OF DETERMINATION, ALL AS DETERMINED IN ACCORDANCE WITH
      GENERALLY ACCEPTED ACCOUNTING PRINCIPLES FROM BORROWER'S FINANCIAL
      STATEMENTS. "EBITDA" MEANS EARNINGS FOR THE TWELVE-MONTH PERIOD ENDING ON
      THE APPLICABLE DATE OF DETERMINATION, BEFORE REDUCTION FOR INTEREST,
      TAXES, DEPRECIATION, AND AMORTIZATION EXPENSE FOR SUCH PERIOD, ALL AS
      DETERMINED IN ACCORDANCE WITH GENERALLY ACCEPTED ACCOUNTING PRINCIPLES
      FROM BORROWER'S FINANCIAL STATEMENTS."

      F. Section III of Schedule A of the Loan Agreement shall be and hereby is
amended by changing the reference in paragraph C thereof from "1.5:1" to
"2.0:1".

      3. SUBSTITUTION AND REPLACEMENT OF REVOLVING LINE OF CREDIT PROMISSORY
NOTE. To reflect the amendments hereby, the Bank and the Borrower agree that the
Revolving Line of Credit Promissory Note in the principal amount of Twenty
Million Dollars ($20,000,000.00) dated March 20, 1996 of WPI GROUP, INC., WPI
ELECTRONICS, INC., WPI MAGNETEC, 




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INC., WPI MICRO PALM, INC., WPI POWER SYSTEMS, INC., WPI TERMIFLEX, INC., WPI
MICRO PROCESSOR SYSTEMS, INC., and WPI DECISIONKEY, INC., payable to the order
of the Bank shall be substituted and replaced in full by the Revolving Line of
Credit Promissory Note in the principal amount of Thirty Million Dollars
($30,000,000.00) of Borrower payable to the order of the Bank attached hereto as
Exhibit A (the "Replacement RLOC Note"), which Replacement RLOC Note shall be
executed contemporaneously with the execution of this Amendment, such that the
indebtedness of WPI GROUP, INC., WPI ELECTRONICS, INC., WPI MAGNETEC, INC., WPI
MICRO PALM, INC., WPI POWER SYSTEMS, INC., WPI TERMIFLEX, INC., WPI MICRO
PROCESSOR SYSTEMS, INC., and WPI DECISIONKEY, INC., currently due and owing to
the Bank under the Revolving Line of Credit Loan shall hereafter be evidenced by
the Replacement RLOC Note.

     4. AMENDMENT OF OTHER LOAN DOCUMENTS. Each of the other Loan Documents,
whether or not specifically referenced herein or hereby, shall be and hereby is
amended to reflect the terms and conditions of this Amendment and to include
within the scope of such Loan Documents and the description of loans and notes
therein, the Revolving Line of Credit Loan as increased, amended and modified
hereby.

     5. REPRESENTATIONS AND WARRANTIES. Each Borrower individually hereby makes,
confirms, reasserts, and restates all of the representations and warranties of
the Borrower under the Loan Agreement and each of the Loan Documents, all as of
the date hereof.

     6. AFFIRMATIVE COVENANTS. Each Borrower individually hereby makes,
confirms, reasserts, and restates all of the Affirmative Covenants of the
Borrower as set forth in the Loan Agreement and each of the Loan Documents, as
amended hereby, all as of the date hereof.

     7. NEGATIVE COVENANTS. Each Borrower individually hereby makes confirms,
reasserts, and restates all of the Negative Covenants of the Borrower as set
forth in the Loan Agreement and each of the Loan Documents, all as of the date
hereof.

     8. NO OTHER MODIFICATIONS. Except as specifically modified or amended
herein or hereby, all of the terms and conditions of each of the Revolving Line
of Credit Loan, the Loan Agreement and the Loan Documents, remain otherwise
unchanged, and in full force and effect, all of which are hereby confirmed and
ratified by the parties hereto.

     9. BANK FEE. For and in consideration of the Bank entering into this
Amendment and increasing the maximum principal amount available to the Borrower
under the Revolving Line of Credit Loan, the Borrower shall pay the Bank a fee
in the amount of Twenty-five Thousand Dollars ($25,000.00); provided, however,
that such fee shall only be due and payable in the event that the Parent issues
additional capital stock within the twelve (12) month period from the date
hereof, and the proceeds of such issuance are used, in whole or in part, to pay
down the outstanding principal amount under the Revolving Line of Credit Loan by
an amount in excess of $1,000,000.00.



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                                       WPI MAGNETEC, INC.


/s/ Michael Tule                       By: /s/ Michael Foster
-----------------------                    -----------------------
                                           Signature and Title
                                           Duly Authorized

                                           Chairman and CEO
                                           -----------------------
                                           Print Name and Title



WITNESSES:                             WPI ELECTRONICS, INC.


/s/ Michael Tule                       By: /s/ Michael Foster
-----------------------                    -----------------------
                                           Signature and Title
                                           Duly Authorized

                                           Chairman and CEO
                                           -----------------------
                                           Print Name and Title


                                       WPI TERMIFLEX, INC.


/s/ Michael Tule                       By: /s/ Michael Foster
-----------------------                    -----------------------
                                           Signature and Title
                                           Duly Authorized

                                           Chairman and CEO
                                           -----------------------
                                           Print Name and Title


                                       WPI MICRO PALM, INC.


/s/ Michael Tule                       By: /s/ Michael Foster
-----------------------                    -----------------------
                                           Signature and Title
                                           Duly Authorized

                                           Chairman and CEO
                                           -----------------------
                                           Print Name and Title


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     10. COSTS AND EXPENSES OF BANK. The Borrower agrees to reimburse the Bank
for all reasonable costs, expenses, and fees, including attorneys' fees,
associated with the documentation of this Amendment. Borrower consents to Bank
charging Borrower's Revolving Line of Credit Loan account for all such costs,
expenses and fees.

      IN WITNESS WHEREOF, the parties have executed and delivered this Amendment
all as of the date first set forth above.

WITNESSES                              FLEET BANK - NH

/s/ Michael Tule                       By: /s/ Mark L. Young
------------------------                   ------------------------------------
                                           Mark L. Young, Senior Vice President


WITNESSES:                             BORROWER:

                                       WPI GROUP, INC.


/s/ Michael Tule                       By: /s/ Michael Foster
-----------------------                    -----------------------
                                           Signature and Title
                                           Duly Authorized

                                           Chairman and CEO
                                           -----------------------
                                           Print Name and Title


                                       WPI POWER SYSTEMS, INC.

/s/ Michael Tule                       By: /s/ Michael Foster
-----------------------                    -----------------------
                                           Signature and Title
                                           Duly Authorized

                                           Chairman and CEO
                                           -----------------------
                                           Print Name and Title



<PAGE>   7

                                       WPI PROCESSOR SYSTEMS, INC.


/s/ Michael Tule                       By: /s/ Michael Foster
-----------------------                    -----------------------
                                           Signature and Title
                                           Duly Authorized

                                           Chairman and CEO
                                           -----------------------
                                           Print Name and Title



                                       WPI DECISIONKEY, INC.


/s/ Michael Tule                       By: /s/ Michael Foster
-----------------------                    -----------------------
                                           Signature and Title
                                           Duly Authorized

                                           Chairman and CEO
                                           -----------------------
                                           Print Name and Title