Nilfisk-Advance CS7000 Fuel Cell EcoFlex, Service Manual

Page: 163 / 440

Engine System - LPG 163 Service Manual – CS7000
Cranking
• When the main machine controller sees the 36v cranking request from the key switch, it sends out 12v on
the crank request circuit to the crank request relay winding. The other side of the winding is grounded
through 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 starter
solenoid engaging the starter to turn the engine crankshaft. The ignition system is functional at this
point, 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 shutdown
relay to de-energize. Ignition request power is then passed through the “closed at rest” contacts to the
fuel 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 to
de-energize.
◦ Battery power is then passed through the “closed at rest” contacts to the main machine controller as
the “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 pressure
shutdown 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 relay
back into the ignition request circuit and to the control relay winding, energizing the control
relay.
2
1
3
5
4
IGN. REQUEST
MAIN
CONTROLLER
FUEL
LOCK-OFF
SOLENOID
OIL SWITCH
(OPEN FOR
PRESSURE)
TEMP. SWITCH
(OPEN FOR
NORMAL TEMP.)
RUN ENABLE SIGNAL
SHUTDOWN Control
CRANK REQUEST
IGNITION REQUEST
ENGINE RUN (12V INPUT)
HIGH COOLANT TEMP Signal
SPEED 2 (12V OUTPUT)
SPEED 3 (12V OUTPUT)
Eng. RPM
Sensor
STARTER
12v BATTERY
ALTERNATOR
IGNITION POWER
FOR IGNITER &
HIGH COOLANT TEMP.
SHUTDOWN RELAY
1
5
4
3
2
CONTROL
RELAY
1
5
4
3
2
IGNITION
REQUEST RELAY
POWER
RELAY
1
5
4
3
2
LOW OIL PRESS.
SHUTDOWN
RELAY
1
5
4
3
2
CRANK
REQUEST
RELAY
1
2
5
6 7
8
9
10
11
12
WOODWARD
L-SERIES
ACTUATOR
3
4
1 2 3
Main Machine
Controller
Carb.
Fuel
Shut Off
Solenoid
85
86 87 87a
30
12v
12v