is closed. Other auxiliary contacts are provided to
perform control functions as required. The circuit inter-
rupter is so connected that it will open automatically
(3) Check the circuit breaker for manual
when either the circuit interrupter actuator switch or the
master switch (on the control cubicle) is place] on the
d. Inspection and Repair.
"OFF" position; this is accomplished independently from
(1) Inspect the circuit breaker for damaged
the underfrequency or any other protective device. In-
terminals, defective insulation and other
terrupting capacity of the main contacts are not less
than 10 times rated current for the contacts.
(2) Inspect the motor mechanism assembly
b. Removal and Installation. Refer
to Figure 131
for evidence of overheating.
remove and install the AC power circuit breaker.
(3) Inspect the assembly for cracks, breaks
and other damage.
(4) Inspect threaded parts for defective
cables and wiring harnesses from the
(5) Replace defective parts as necessary.
(2) Test the ink connections, contacts,
terminals and motor assembly for
Section V. ELECTRIC GOVERNOR
(1) Figures 1 and 128 illustrate the
connections of the control unit to other
a. The electric governor is a speed (frequency)
regulating device for the engine of the generator set. It
offers fast response and minimum speed (frequency
(2) The transistor inverter inverts 24 VDC to
deviations) with load fluctuations. It features electrical
approximately 1000 cps AC through the
frequency sensing, electrical load sensing, has static
components, and no electronic tubes. The governor is
24 volt 1,000 cps output from the inverter
effective on load sharing and paralleling of two or mare
is applied to the magnetic amplifier power
engine generator sets on an isochronous basis.
b. The electric governor consists primarily of an
electric control unit, a load measurement unit, and an
electro-hydraulic throttle actuator.
static magnetic components with
components should be necessary.
89. Electric Control Unit
a. General. The electric control unit (fig. 132) contains
a transistor inverter, magnetic amplifier circuit; a
frequency sensing and frequency reference circuit, a
throttle position feedback circuit, and a paralleling
Figure132 Electric governor control unit.