Danfoss troubleshooting answers
8 questions with answers cited from the manufacturer manuals.
- 0Danfoss FC 302 Alarm 29: Heat Sink Temp after running loaded, what to check?
Alarm 29 on a Danfoss VLT FC 302 indicates that the maximum heat sink temperature has been exceeded. This alarm will not reset until the heat sink cools down below a defined temperature, with trip and reset points varyin…
- 0Danfoss FC 302 Alarm 10: Motor ETR Overtemp, what to check?
Alarm 10 on a Danfoss VLT FC 302 indicates that the drive's electronic thermal protection (ETR) calculates the motor is too hot, likely due to running with more than 100% overload for an extended period. This can be conf…
- 0Danfoss FC 302 trips Alarm 9 after running loaded for a while, why?
Alarm 9 (Inverter Overload) on a Danfoss FC 302 indicates the drive has operated above 100% overload for an extended period, causing its electronic thermal inverter protection counter to reach 100%. The drive cannot be r…
- 0Danfoss FC 302 Alarm 4: what to check for mains phase loss?
Alarm 4 on a Danfoss VLT FC 302 indicates a missing phase on the supply side or excessive mains voltage imbalance. This alarm can also appear due to a fault in the input rectifier. It typically occurs while the drive is …
- 0Danfoss FC 302 trips A8 DC Undervoltage at power-up, what to check?
Alarm 8 on a Danfoss VLT FC 302 indicates that the DC-link voltage has dropped below its undervoltage limit. If no 24 V DC back-up supply is connected, the drive will trip after a fixed delay that varies with unit size. …
- 0Danfoss FC 302 trips A7 on ramp-down, what to check?
Alarm 7 (DC Overvoltage) on a Danfoss VLT FC 302 indicates the DC-link voltage exceeded its limit, causing the drive to trip. This typically occurs when the motor regenerates energy back to the drive faster than it can b…
- 0Danfoss FC 302 Alarm 14: what to check first for an earth fault?
Alarm 14 on a Danfoss VLT FC 302 indicates an Earth (Ground) Fault, meaning current is flowing from an output phase to ground. This can occur in the motor cable or the motor itself. The drive detects this by comparing th…
- 0Danfoss FC 302 trips A13 during ramp-up, what to check?
Alarm 13 (Overcurrent) on a Danfoss VLT FC 302 indicates the output current has exceeded the inverter's peak current limit, which is approximately 200% of the drive's rated current. This alarm is typically preceded by a …