at the initial and final ambient temperatures.
If the drift in paragraph d is
excessive, realign the control
unit following the procedure out-
lined in paragraph 7-8.
e. At constant ambient temperature, constant load,
constant voltage and constant barometric pressure,
the set frequency should remain within a bandwidth
of 1 percent of rated frequency for a period of 4 hours.
If this bandwidth has been exceeded, realign the
control unit in accordance with paragraph 7-8.
f. If the preceding solutions to the specific
problem do not resolve the problems, replace and
repair the control unit, actuator (para 13-3 thru
13-8) or load measuring unit (para 8-15 thru
8-19) as required.
Refer to figure 7-1 and remove in the order of
7-4. Disassembly and Repair
a. Disassemble electric governor control unit,
if required, as illustrated in figure 7-2.
Disassembly and repair of electric
governor control unit at the field
level is restricted to removal of
the cover, connectors, potentio-
meters and test jacks.
disassembly requires unpotting and
the following disassembly can be
performed by depot maintenance
b. Remove cover and components installed on
cover in the order of sequence numbers (1 thru 15).
Tag and unsolder wires for the
components on the cover.
(1) Replace defective test jacks, potentiometers
(2) Repair procedures for individual wires of a
wiring harness are covered in the Operator and
Organizational Maintenance Manual.
Remove six screws and lockwashers from cover
of control unit.
Lift cover slightly
slight angle to keep the connectors
out of the potting compound.
d. Place the complete unit in a
trolled oven, large enough to allow
completely around the unit.
and set at a
air to circulate
The melting temperature of the
potting compound is 165 F. The
flash point is 515°F. Do not unpot
by placing unit on a hot plate type
surface or by using an open flame.
e. Set the oven temperature at 180°F to 185°F
and allow the unit to soak until the potting compound
The normal soak period at this temper-
ature is 11 to 12 hours.
Use care when handling the hot potting
compound. It can cause severe in-
jury to personnel.
f. Using heavy gloves and wearing safety
glasses, remove the printed circuit board from the
melted putting compound. Lift the board s1owly,
allowing the potting compound to drain off the com-
g. Set the printed circuit board with transformers
on the bottom on a drain board and allow it to cool
to room temperature.
h. Remove screw (4) and lockwashers (5) which
attach connectors (P1, J3, P5, P2) to cover.
i. Tag wiring and remove harness (6).
j. Disassemble remaining components mounted
on cover in accordance with index numbers 7 through
7-5. Cleaning and Inspection.
a. Clean all parts with a cloth dampened in
cleaning solvent Federal Specification P-D-680 and
b. Inspect for cracks, breaks, damaged connectors,
damaged terminals, defective wiring, and defective
Check potentiometer for continuity,
resistance, and wiring for open insulation.
7 - 6 .
Tests and Repair.
a. Perform test as outlined in figures 7-3 thru
Mount circuit card as shown in
figure 7-11 prior to test.
b. Resistance Test (50/60 Hz) . Refer to Table
7-1 and perform resistance test.
c. See figure 1-4 and 1-5 for schematic diagrams.
d. See table 7-2 for values of individual comp-
onents. When measuring individual components, dis-
connect at least one lead to prevent feedback readings.