OPERATION OF THE CIRCUIT
The circuit in Figure 46–9 shows the initial start up of the ice maker. It is assumed that the master switch and the bin thermostat switch are closed. A circuit is first completed through coil B. This closes contact B and completes a circuit through the auger delay pressure control switch to the auger drive motor. The normally closed centrifugal switch contact completes a circuit to the start winding and permits the auger drive motor to start.
The normal running mode of the circuit is shown in Figure 46–10. In this phase of operation, it is assumed that the auger drive motor is operating at the proper speed and the centrifugal switch
connected in series with the compressor contactor has closed and permitted the compressor to start. The suction pressure has dropped low enough to permit the auger delay pressure control switch contacts to change position. The bottom condenser fan motor is in operation and the top fan motor may or may not be operating depending on the pressure on the high side of the refrigeration system.
In the schematic shown in Figure 46–11, it is assumed that the bin thermostat has been satisfied and has opened its contact. This opens the circuit to coils B and C and stops the operation of the compressor. The auger drive motor will continue to operate until the pressure on the low side of the refrigeration system increases enough to reset the auger delay pressure switch. The circuit will then be back in its original, deenergized position.
The circuit in Figure 46–12 shows the operation of the circuit when the auger drive motor slows down enough to cause the centrifugal switch in
series with the compressor contactor to open. If this occurs, the compressor will be disconnected from the line and stop operating. A current path is maintained through the auger drive motor and auger delay pressure switch. Notice also that a current path is maintained through relay coil B. If the auger drive motor speed does not increase sufficiently before the auger delay switch changes position, the closed B contact will provide a current path through the reset auger delay switch and permit the auger drive motor to continue operation.
