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| Illustration 1 | g01280139 |
Charging system circuit | |
The components of the charging system circuit are the main fuse, the batteries, the alternator, the alternator circuit breaker, and the Caterpillar Monitoring System ECM.
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| Illustration 2 | g01268924 |
View of battery compartment (1) Batteries (2) Main fuse | |
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| Illustration 3 | g01268925 |
Right side view of engine (3) Alternator | |
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| Illustration 4 | g01268922 |
Rear view of engine (4) Alternator circuit breaker | |
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| Illustration 5 | g03739339 |
(5) Caterpillar Monitoring System ECM (behind display) (6) Electrical system alert indicator | |
With the battery disconnect switch in the ON position, 24 V power is supplied from batteries (1) via alternator circuit breaker (4) to alternator (3). With the key start switch in the ON position, 24 V power is supplied from batteries (1) via circuit breaker 7 to Caterpillar Monitoring System ECM (5) .
24 V power is supplied to alternator (3) from batteries (1) via main fuse (2) and alternator circuit breaker (4). Alternator circuit breaker (4) protects alternator (3) and the wiring harness from circuit overload.
With the engine running at high idle, alternator (3) generates a charge of 26 to 29 V. A voltage signal is supplied from alternator (3) to Caterpillar Monitoring System ECM (5). When the voltage signal is within the normal operating range, Caterpillar Monitoring System ECM (5) will turn off electrical system alert indicator (6). When the voltage signal is outside the normal operating range, electrical system alert indicator (6) will be on, indicating a fault.