Danfoss VLT HVAC Drive FC 102 Operating Manual page 132

Operating Guide | VLT® HVAC Drive FC 102
9.3.4 WARNING/ALARM 3, No Motor
Cause
No motor is connected to the output of the drive.
9.3.5 WARNING/ALARM 4, Mains Phase Loss
Cause
A phase is missing on the supply side, or the mains voltage imbalance is too high. This message also appears for a fault in the input
rectifier. Options are programmed in parameter 14-12 Function at Mains Imbalance.
Troubleshooting
• Check the supply voltage and supply currents to the drive.
9.3.6 WARNING 5, DC Link Voltage High
Cause
The DC-link voltage (DC) is higher than the high-voltage warning limit. The limit depends on the drive voltage rating. The unit is still
active.
9.3.7 WARNING 6, DC Link Voltage Low
Cause
The DC-link voltage (DC) is lower than the low voltage warning limit. The limit depends on the drive voltage rating. The unit is still
active.
9.3.8 WARNING/ALARM 7, DC Overvoltage
Cause
If the DC-link voltage exceeds the limit, the drive trips after a certain time.
Troubleshooting
• Connect a brake resistor.
• Extend the ramp time.
• Change the ramp type.
• Activate the functions in parameter 2-10 Brake Function.
• Increase parameter 14-26 Trip Delay at Inverter Fault.
• If the alarm/warning occurs during a power sag, use kinetic back-up (parameter 14-10 Mains Failure).
132 | Danfoss A/S © 2018.10
Maintenance, Diagnostics, and
Troubleshooting
AQ262141314214en-000101 / 130R0880