Component Function; Test Plug; Sensors; Reset Operation - Cornelius 322 Service/Installation Manual

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 temperature.
S Condenser 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.
S Suction 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 start-up process.
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 5 VDC ± 0.2 output voltage. If not, replace the circuit
board.
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COMPONENT FUNCTION

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