NME454, 654 & FME504, 804
ELECTRICAL SEQUENCE:
There are 7 indicator lights on the control board:
Glowing. Glows when there is water in the reservoir.
Glowing. Glows when the control board has power and is functional.
Service. Red. Normally Off.
Freeze. Red. Normally glowing when making ice.
Bin Full. Red. Normally Off when making ice.
LED1. White. Located next to the board’s Compressor Relay. Normally Glowing when making ice.
LED3. White. Located next to the board’s Auger
Motor Relay. Normally Glowing when making ice.
If the machine is switched off at the mode switch, but is otherwise ready to go, switching the mode switch to ON does the following:
The
If there is water in the reservoir the
After 10 seconds the Freeze, LED1 and LED3 lights glow and the machine starts up.
Start Up:
The compressor relay and auger motor relay become energized, connecting power to the windings of the auger motor and contactor coil.
The contactor is energized, connecting power to the compressor, and the compressor starts.
As ice is made it passes between the ice level sensors but because it is not a continuous stream it only interupts the sensor’s infrared beam momentarily. The bin full light remains off and the machine stays on until ice builds up in the bin and blocks the path between the sensors for 6 seconds or longer. When that occurs the bin full light glows and the machine shuts down.
Shut Down:
The compressor relay opens, LED1 goes out.
The compressor contactor opens
The compressor stops
The auger motor stays on for 1 more minute, clearing out ice in the evaporator, and then
The auger motor relay opens, LED3 goes out and the auger motor stops.
The compressor will not restart until 2 minutes or more have passed after the last shut down.
If the path between the ice level sensors remains clear for more than 10 seconds the ice machine will restart.
Control Board Protection Devices
When the water level in the reservoir falls below the water level sensor’s tip, the
If the auger drive motor current becomes excessive the compressor and auger drive motor will be switched Off and the Service light will blink. The control board will restart the auger drive motor in 4 minutes. If during the first 60 seconds after restart the auger motor current stays within limits, the compressor is restarted and the machine returns to normal operation. If the auger motor’s current is excessive within 60 seconds after the restart, the process will be repeated once more. If during that try the current is still excessive the machine shuts down and must be manually reset. The service
light will then be glowing continuously.
To Reset: Disconnect and reconnect electrical power to the ice machine.
Other Protection Devices:
If the high pressure cut out switch opens the machine will stop immediately. It will automatically reset when the pressure falls below its cut in point.
If the low pressure cut out switch opens the machine will stop immediately. It will automatically reset when the pressure rises above its cut in point.
The mode (on - off) switch is the manual control for the complete machine, but it is not a service disconnect.
January 2007
Page 13