Washdown System Electrical Schematic
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| Illustration 1 | g01189256 |
Electric Screed Heaters
When the main power relay is energized, power is available at the fuel spray pump circuit breaker. Power transfers from the circuit breaker to contact "2" of the fuel pump switch. When the fuel pump switch is in the OFF position, the circuits across the fuel pump switch are open.
When the fuel pump switch is in the ON position, contact "2" and contact "3" of the switch are closed. In this situation, power illuminates the fuel pump indicator, and power operates the fuel pump motor. The fuel pump motor will operate until the fuel pump switch is returned to the OFF position.
Diesel Screed Heaters
Power Distribution
When the main power relay is energized, power is available at the fuel spray pump circuit breaker. Power transfers from the circuit breaker to contact "2" of the fuel pump switch. When the fuel pump switch is in the OFF position, the circuits across the fuel pump switch are open.
Fuel Pump Switch TIME
When the fuel pump switch is in the TIME position, contact "1" and contact "2" of the switch are closed. Power is transfered to the fuel pump timer. As a result, the timer begins counting. As long as the allowed amount of time has not elapsed power transfers to the fuel pump indicator and to the fuel pump motor.
The fuel pump motor will operate until either of the following conditions are met:
- The fuel pump switch is moved to OFF.
- The allowed time on the timer has elapsed.
Fuel Pump Switch ON
When the fuel pump switch is in the ON position, contact "2" and contact "3" of the switch are closed. In this situation, power illuminates the fuel pump indicator. Power operates the fuel pump motor. The fuel pump motor will operate until the fuel pump switch is returned to the OFF position.