5284792-UIM-A-0317
18
Johnson Controls Unitary Products
TABLE 9:
Troubleshooting – Fault and Protection Table
Fault and Protection
Check and Handling
Compressor phase over current
1. Check the U/V/W connections on drive side.
2. Check the compressor motor windings.
3. Check the compressor is operating within specified limits.
4. Sensor on drive not reading properly - Replace the drive.
Compressor phase current fold back timeout
Check if the compressor is operating outside the specified speed range.
AC input over current
1. Check the line voltage if it is < 187VAC.
2. Check the line voltage for noise.
3. Check the compressor is operating with in specified limits.
4. If the problem still persist, then it's possibly a drive component issue. Replace the drive.
AC input current sampling fault
Sensor on drive not reading properly.
DC bus over voltage
1. Check the line voltage if it is > 265VAC.
2. Check the DC bus voltage if it is > 385VDC.
3. Check the compressor is operating with in specified limits.
DC bus under voltage
1. Check the line voltage if it is < 187VAC.
2. Check the DC bus voltage if it is < 385VDC.
3. Check the compressor is operating with in specified limits.
AC input over voltage
1. Check the line voltage if it is > 265VAC.
2. Check the DC bus voltage if it is > 385VDC.
3. Check the compressor is operating with in specified limits.
AC input under voltage
1. Check the line voltage if it is < 187VAC.
2. Check the DC bus voltage if it is < 385VDC.
3. Check the compressor is operating with in specified limits.
Power module over temp
PFC-IGBT over temp
1. Verify proper airflow over the heatsink of the drive. Remove any obstructions.
2. Check the compressor is operating with in specified limits.
3. If the problem still persists, replace the drive.
Lost rotor position
Compressor phase current imbalance
1. Check the U/V/W connections on drive side & compressor side.
2. Check the compressor motor windings.
Microelectronic fault
EEPROM fault
1. Check the DC bus voltage > 187VDC.
2. Power cycle the drive.
3. If problem persists, replace the drive.
Power module temp low or sensor open fault
Temperature sensing device on the drive are possibly defective.
If problem persists, replace the drive.
DC Bus Voltage Low
1. Check the line voltage if it is < 187VAC.
2. Check the DC bus voltage if it is < 385VDC.
3. Check the compressor is operating with in specified limits.
AC input current fold back timeout.
1. Check the line voltage if it is < 187VAC.
2. Check the compressor is operating with in specified limits.
3. If problem persists, replace the drive.
Mod bus communication lost
1. Check mod-bus communication cable connections.
2. Check the communication parameters are set right.
3. Power cycle the drive.
4. If problem persists, replace the drive.
Power module temp high
PFC-IGBT high temp
1. Verify proper airflow over the heatsink of the drive. Remove any obstructions.
2. Check the compressor is operating with in specified limits.
3. If the problem still persists, replace the drive.
PFC MCU and DSP communication lost
COM MCU and DSP communication lost
1. Check mod-bus communication cable connections.
2. Check the communication parameters are set right.
3. Power cycle the drive.
4. If problem persists, replace the drive.
PFC-IGBT temp low or sensor open fault
Power module temp. fold back timeout
1. Verify proper airflow over the heatsink of the drive. Remove any obstructions.
2. Check the compressor is operating with in specified limits.
3. If the problem still persists, replace the drive.
Compressor model configuration error
Compressor model and configuration code do not match.
High pressure sensor type configuration error
Pressure sensor and configuration code do not match.
AC input voltage sampling fault
Sensor on drive not reading properly.
DC bus voltage sampling fault
Sensor on drive not reading properly.
Fault limit lockout
Certain faults have a trip limit, see mod bus map for details
