CONTROL PANEL (TYPE 5)
SYSTEMS OPERATION
Engine Shutdown Caused by Oil
Pressure Failure
Because crank termination is the job of the speed switch (C.T.S.), a
time delay relay-(TDR) and time delay auxiliary (TDX) is required for oil
pressure build-up after start-up.
When the engine is started and C.T.S. (crank termination switch)
closes (at 600 rpm), the arming relay (AR) is energized. Contact (AR2)
opens to de-energize the starting motor. Contact (AR1) closes to lock-in
the (AR) relay. At this same time, (TDR) begins a 9 second delay. If oil
pressure comes up and (OPS) goes to the N.O. position, the 9 second
delay is bypassed and (TDX) will be energized immediately. At this time,
the oil pressure failure circuit is armed thru the (TDX) contact.
NOTE: The shutdown and air shut-off circuits are also
armed by TDX.
If a loss of oil pressure occurs, the oil pressure switch (OPS) will
close. This causes (OPR) to energize through the contact TDX and
diode Dl. Then (OPR1) contact opens to de-energize the run relay (RR)
circuit. Contact (OPR2) closes to lock-in the relay (OPR) thru the
OFF/RESET switch.
The engine will shut down when the normally closed (RR2) contact
closes to energize the shutdown solenoid (SS).
If the engine should accidentally be started without oil in the
crankcase, it will shutdown after the 9 second delay.
The time delay relay (TDR) also provides a 70 second delay before
opening the shutdown and air shut-off solenoids after the engine stops.
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