Engine Start/Stop Cranking Control

3_540_04
Page Navigation
61

MIL-HDBK-1003/11

7.3.2 Engine Start/Stop Cranking Control. Engine star/stop control logic

circuitry may be mounted on the unit or in the generator switchgear. The

start cycle is initiated by a signal to the cranking motor which starts the

engine. The stop sequence can be initiated manually by a stop button,

automatically by engine shutdown devices, or by protective relays. In the

automatic mode, when the cranking cycle is initiated, it will operate for a

preset period usually of one-minute duration with alternate crank and rest

periods of about 10 seconds. If the engine does not start during this

cycle, the cranking circuitry is shut down. Emergency stops may be

initiated by the engine and generator protective devices and, when

activated,shut down the engine and disconnect the generator from the load.

7.3.3 Operation Mode Switch. A selector switch is located on the engine

gage board to select automatic or manual starting and stopping modes when

both types of operation are required.

7.4 Instrumentation. Instrumentation is provided to monitor the engine and

generator operation and is mounted on the engine gage board and at the

generator control panel. In small plants all instrumentation may be

located at the diesel generator. The number of instruments may vary

depending on the size and complexity of the plant. The use of solid-state

control devices and instrumentation is recommended.