TURBOCHARGER GP 2P4664 - Caterpillar

ECS In AUTO Position
IC Closed
Simplified schematicWhen engine control switch (ECS) is in the auto position, ECS contacts (9 and 10) (lines 56 and 57) are also closed. When initiating contact (IC) (line 59) is closed, the run relay (RR) (line 56) energizes. This causes RR contacts (6 and 9) (line 17) and RR (7 and 4) (line 20) to close. It also opens RR (8 and 2) (line 15).RR (8 and 2) (line 15) - Normally open (N.C.) contact across RR (8 and 2) opens to prevent current flow to terminal 6 on the time delay (line 15).RR (6 and 9) (line 17) - Normally open (N.O.) contact across RR (6 and 9) closes to energize the starting motor magnetic switch (SMMS1) (line 17). SMMS1 closes its contact (line 6) to energize the pinion solenoid #1 (PS1) (line 6) which in turn closes its contact (line 5) to energize the starting motor #1 (SM1) (line 5). Also, the overcrank timer (OCT) (line 21) starts its timer. After the engine cranks for approximately 30 seconds without the engine starting, OCT will energize the overcrank fault relay (OCR) (line 35).RR (7 and 4) (line 20) - Normally open (N.O.) contact across RR (7 and 4) closes. This connects the engine speed switch (terminal 10) to the arming delay timer (ADT) (terminal 1). When the engine reaches 400 rpm the ADT will energize.Once the engine has started and reached approximately 400 rpm:The engine speed switch's (ESS) crank termination (CT) (contacts 11 and 10) (line 20) close. This energizes the ADT (line 20) which has a 10 second delay. The delay allows time for initial oil pressure to build-up causing the oil pressure switch (OPS) (line 39) to open at 93.0 21 kPa (13.5 3.5 psi). This prevents the oil pressure fault relay (OPR) (line 39) and light (OPL) (line 40) from energizing oo normal start-up and shutdown.TD (6 and 7) (line 15) - Time delay (line 23) is energized when ESS (CT) contacts (10 and 11) (line 20) are closed. At that time TD contacts (6 and 7) (line 15) close. The contacts will remain closed for approximately 70 seconds after the engine is shut down.As the engine starts and ESS senses a speed of 400 rpm through the magnetic speed pickup (MPU) (line 62), the ESS opens the starting motor circuit by opening the crank termination switch contact across ESS (CT) (11 and 12) (line 17).
Simplified SchematicWhen engine control switch (ECS) is in the auto position, ECS contacts (5 and 6) (line 36) are also closed. This provides a path to latch in one of the fault relays (OCR, OPR, WTR or OSR) should a fault occur.IC Open
If the engine is running with the ECS in the auto position, ECS contacts (9 and 10) (lines 56 and 57) and initiating contact (IC) (line 59) are closed. When the IC opens, run relay (RR) (line 56) de-energizes. This closes RR contacts (8 and 2) (line 15) which lets current