TM5-6115-593-34 NAVFAC P-8-631-34 T0-35C2-3-463-2 switch to the 60 Hz position. h. Loosen  locknut  and  adjust  R103  (54,  figure 4-1)    for    60    Hz    operation.        Monitor    the FREQUENCY meter on the Control Cubicle. Tighten locknut (55). i. Proceed to normal operation of the set and toggle the FREQUENCY SELECTOR switch to the 50 or 60 Hz position depending on the load requirement. j. Run the engine until the coolant temperature has stabilized and is normal. k. Turn the GAIN potentiometer clockwise until the  generator  set  becomes  unstable.    Then back  off  this  adjustment  until  generator  set just becomes stable. l. Rotate   the   STABILITY   potentiometer   1/4 turn counterclockwise. NOTE The  governor  controller  in  the  master unit   may   have   to   be   readjusted   to obtain     a     balanced     load     condition between the master set and other units in parallel operation.  KW meters must be monitored for equal readings (proper load sharing). 4-14.      REMOVAL   AND   REPLACEMENT.      To   gain access to the governor controller, access panel must be removed first, see paragraph 4-2. WARNING BEFORE STARTING ANY MAINTENANCE PROCEDURE, SET MAINTENANCE LOCKOUT SWITCH TO LOCKOUT.    DISCONNECT  NEGATIVE CABLE  FROM  BATTERIES.    REMOVE EXTERNAL POWER BY OPENING CB101 (EXTERNAL POWER BREAKER) AND DISCONNECTING POWER  CABLE  FROM  RECEPTACLE J101 (120V RECEPTACLE). a. REMOVAL. (1) Disconnect and tag all wires connected to the two terminal boards. Remove warning plate to gain access to terminals 1, 2 and 3 connections. (2) Referring to figure 4-1, remove the six screws   (52)   and   nuts   (53)   attaching the governor controller (56) to mounting bracket (62). (3) Remove     potentiometer     R103     (54) from mounting bracket (62) by removing   shaftlock   (55).      Mounting bracket    (62)    may    be    removed    by removing six screws (61). b. Replacement. (1) Attach potentiometer (54) onto mounting  bracket  (62)  with  shaftlock (55). (2) Replace   mounting   bracket   (62)   with six screws (61). (3) Attach    governor    controller    (56)    to mounting bracket (62) with six screws (52) and nuts (53). (4) Connect wires to terminal boards.  Be sure   to   connect   potentiometer   (54) leads to terminals 16 and 20. Remove   tags   from   wires.      Replace warning plate. (5) Perform     adjustment     procedures     in accordance with paragraph 4-13. 4-15.      TESTING.      Bench   testing   is   accomplished   by simulating   various   parameters   connected   to   the   unit. The following items are required for the test setup: 20 to 40V   DC   source;   2   SPST   switches;   35-ohm   10-watt resistor;  AC  signal  generator,  capable  of  producing  60 Hz  with  10  rms  volts  output;  and  a  DC  voltmeter  to  25 volts. NOTE Before  performing  test,  visually  check for   damage   to   the   chassis,   terminal block, or printed circuit board. a. Make    the    following    connections    to    the governor  A106  terminal  boards  (see  figure 4-5). (1) Connect 20 to 40V DC source to 12(+) and 13(-) . 4-10