Control Circuit Operation - Carrier 69GL15-114 Operation And Service

2.4 CONTROL CIRCUIT OPERATION

WARNING
Beware of moving V-Belts and belt driven
components.
CAUTION
The generator set circuit breaker must be in the
ON position in order to supply power to the
refrigeration unit.
When the glow plug switch is held in the pre-heat
position, current flows to the glow plugs. The glow plugs
(starting aids) provide a source of heat to pre-heat the
combustion chamber during start-up.
In order to start engine, hold the glow plug switch in
the PREHEAT position for the recommended time as
detailed in section 2.3.a. and then hold the ignition
(Start-Run-Off) switch in the START position. With
ignition switch in the START position, starter solenoid is
energized closing starter motor contactor contacts (SS),
which energizes starter motor. The starter motor turns
over the engine resulting in pumping fuel to the engine
cylinders by the injection pump. This fuel is ignited by
heat of compression; thus starting the engine.
When the engine has developed sufficient oil pres-
sure, oil pressure safety switch contacts close to maintain
a circuit to the fuel solenoid (FS). The glow plug switch is
then released and the ignition switch is released to the
RUN position. Releasing glow plug switch de-energizes
the glow plugs.
Total time meter is energized simultaneously with the
fuel solenoid.
With the engine running, the alternator provides
12-volt d-c power to operate the control system and
charge the battery.
2-3