18 Power Supply Phase Error (Log Alarm)

Thermo King Alarm Code

Description	Corrective Action
Power Supply Phase Error (Check Alarm One or more frequency inputs are missing for more than 20 seconds. Indicates: One phase on power line is missing Defective fuse on relay board Defective digital inputs on relay board Defective controller	Enter Data menu and view voltage reading on each phase. Check all fuses. Check cable No.1 on relay board. Check cable No.1 between controller and relay board. Replace relay board. Check voltage reading on each phase.

NOTE: * If both alarms 16 and 17 are activated, the alarms are caused by a large difference in measured amps. Enter Manual Function Test menu and start condenser fan. Check the condenser fan amps measurement. If necessary, check the resistance in the motor between CF1 and CF2, CF2 and CF3, and CF1 and CF3. Resistance readings should be equal (approximately 25 Ohms).