COMPONENT FUNCTION (CIRCUIT BOARD ETC.)
TEST PLUG
Board manufactures check point. DO NOT ATTEMPT ANY VOLTAGE CHECKS AT THESE PINS.
SENSORS
Condenser sensor (WHITE) and suction line sensor (BROWN) are thermistors rated 1k ohm at room tempera- ture.
SCondenser sensor signals the circuit board for fan cycling and also serves as the high temperature safety shut down. The red “Error LED” will flash on and off every second, during high temperature safety shut down. Product is functionally shut down. Reset procedure must be performed to restart product operation.
SSuction line sensor signals the circuit board the suction line temperature, to control ice bridge thickness.
Also the sensor serves as suction line high temperature signal (Cuber has 6 minutes to reduce suction line temperature to 40°F (4.4°C) in the freeze mode). The red “Error LED” will be steady on. Should this time frame not be met, product is functionally inoperative during this safety shut down. Reset procedure must be performed to restart product operation.
RESET OPERATION
When Cuber is functionally shut down and red “Error LED” is operational, the Cuber power switch must be turned off for 5 seconds and returned to the ON position to reset the circuit board and allow the Cuber to restart operation.
Evaporator Switches
Proximity Switches are half mounted to the water curtain, and the other half mounted to the evaporator side rail.
Switch Notes
1.Manually holding the curtain open during freeze mode will shut the Cuber down in 5 seconds.
2.During harvest cycle, if curtain is open for 10 seconds, the water pump will stop. The compressor will oper- ate for 20 additional seconds before Cuber shut down takes place. When the water curtain is closed, the Cuber will begin the normal
3.In single evaporator machines, the proximity switch connection must be on the top (RH) connection on the circuit board.
4.In dual evaporator machines, both RH and LH switches must open and reset to start the next freeze mode.
Harvest Safety Termination
After 4 minutes in the harvest mode, the safety timer in the circuit board will terminate the harvest mode and place the Cuber back into a freeze mode. This safety cycle will protect the evaporator, etc. should the product fail to terminate the harvest mode for any reason.
VOLTAGE CHECKS
Evaporator Proximity Switch
Turn Cuber power switch OFF. Disconnect proximity switch plug(s) from the circuit board. Use a digital multime- ter set for D.C. Voltage; turn power switch ON, connect leads of meter across the top two terminal pins on the board, (for the switch being tested), meter should read 5VDC ± 0.2 output voltage. If not, replace the circuit board.
NOTE: The proximity switch on the IACS 227 or the IWCS 227 is mounted inside the right hand evaporator side rail. To test the switch, make the voltage test at the circuit board. To replace the switch, remove the upper right hand side service panel. Carefully remove the Mylar shield to gain access to the two nylon screws that hold the proximity switch. Remove the screws and the switch through the service opening. After installing the new switch, replace the Mylar shield and seal with a bead of silicone sealant.
166240004 | 24 | 12/1/94 | |
Rev 3/4/96 | |||
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