CLUTCH GP 7T9402 - Caterpillar

Illustration 1 g01149562
Main power relay circuit
The components of the main power relay circuit are the key start switch, the fire suppression control loop receptacle (foam type), the fire suppression control loop plug (dry powder type), and the main relay magnetic switch.
Illustration 2 g01046946
Dash panel
(1) Key start switch
(2) OFF position
(3) ON position
Illustration 3 g01046948
Side view of cab
(4) Main relay magnetic switch
Illustration 4 g01047446
View of upper cab (cover removed)
(5) Fire suppression control loop receptacle (foam type)
Illustration 5 g01048279
Cab
(6) Fire suppression control loop plug (dry powder type) When the key start switch is in OFF position (2), the main relay magnetic switch is not energized and the relay contacts are open. In this condition, 24 volt power is present in circuit breaker #11, circuit breaker #12, circuit breaker #13, and circuit breaker #14.When key start switch (1) is turned to ON position (3), 24 volt power is supplied via fire suppression control loop receptacle (foam type) (5) and fire suppression control loop plug (dry powder type) (6) to main relay magnetic switch (4). The main relay magnetic switch is energized and the relay contacts are closed. 24 volt power is now supplied to all remaining circuit breakers.