Engine System - LPG163Service Manual – CS7000Cranking• When the main machine controller sees the 36v cranking request from the key switch, it sends out 12v onthe crank request circuit to the crank request relay winding. The other side of the winding is groundedthrough pin 9 of the actuator (as long as there is not a shutdown condition within the L-Series actuator).This energizes the crank request relay and battery power is passed through the contacts to the startersolenoid engaging the starter to turn the engine crankshaft. The ignition system is functional at thispoint, but there is not any fuel yet so the engine is not able to start.• Once oil pressure builds up, the oil pressure switch opens.– The loss of ground through the oil pressure switch causes the high coolant temperature shutdownrelay to de-energize. Ignition request power is then passed through the “closed at rest” contacts to thefuel lock off solenoid allowing fuel to flow and the engine to start.– The loss of ground through the oil pressure switch also causes the low oil pressure shutdown relay tode-energize.◦ Battery power is then passed through the “closed at rest” contacts to the main machine controller asthe “engine run” signal and to the Woodward L series actuator.− From this point on, the “run enable” signal to the actuator is maintained by the low oil pressureshutdown relay.◦ The same power is also passed to the power relay coil energizing the relay.− Battery power is then passed through the “closed when energized” contacts of the power relayback into the ignition request circuit and to the control relay winding, energizing the controlrelay.2135 4IGN. REQUESTMAINCONTROLLERFUELLOCK-OFFSOLENOIDOIL SWITCH(OPEN FORPRESSURE)TEMP. SWITCH(OPEN FORNORMAL TEMP.)RUN ENABLE SIGNALSHUTDOWN ControlCRANK REQUESTIGNITION REQUESTENGINE RUN (12V INPUT)HIGH COOLANT TEMP SignalSPEED 2 (12V OUTPUT)SPEED 3 (12V OUTPUT)Eng. RPMSensorSTARTER12v BATTERYALTERNATORIGNITION POWERFOR IGNITER &HIGH COOLANT TEMP.SHUTDOWN RELAY1 5 432CONTROLRELAY1 5 432IGNITIONREQUEST RELAYPOWERRELAY1 5 432LOW OIL PRESS.SHUTDOWNRELAY 1 5 432CRANKREQUESTRELAY1256 789101112WOODWARDL-SERIESACTUATOR341 2 3Main MachineControllerCarb.FuelShut OffSolenoid8586 87 87a3012v12v
