302 StarCool Alarm Codes And Actions

302  RH invalid
Description Relative Humidity Sensor Invalid
Cause Indication of defective relative humidity sensor or its measuring circuitry
Trouble
shooting
Possible causes:

  • Relative humidity sensor RH or cable defective.
  • X10 cable is defective.
  • Main controller defective.

Trouble shooting:

Disconnect the cable for RH on the main controller according to the wiring
schematics inside the control cabinet and from the RH sensor.

  1. Try to correct the error by uploading the latest software version to the controller.
  2. If the cable by inspection is defective, replace cable.
  3. Dismount the sensor from the cable. Dismount the cable terminals from the controller. Measure the resistance between the terminals at the controller end. If the resistance is less than (<) 230 Ω, the cable is defective and must be replaced.
  4. Mount the cable for RH in controller cabinet and on the sensor. Disconnect signal wire on main controller. Measure voltage between wire and GND on the main controller. If voltage is below 0.5 V DC, sensor or connection between sensor and cable is defective. If voltage is between 0.5 V DC and 10 V DC, continue to 5).
  5. Mount signal wire. Measure voltage between SIGNAL and GND. If voltage is between 0.5 V DC and 10 V DC and this alarm is still active, replace main controller.
  6. Before replacing main controller see “16.1 Trouble shooting for Star Cool main controller” p. 60
Criteria Value below alarm limit 10% RH or above 110% RH. Value invalid for 120 sec. for alarm activation.