OHF [Drive Overheat]
- Drive temperature too high.
- Check the motor load, the drive ventilation and the environment. Wait for the drive to cool before restarting.

    OLF [Motor Overload]
- Triggered by excessive motor current.
- [Cold stator resist.] (rSC) parameter value incorrect.
- Check the [Mot. therm. current] (ItH) setting, page 33, of the motor thermal protection, check the motor load. Wait for the drive to cool before restarting.
- Remeasure [Cold stator resist.] (rSC), page 42.

    OPF [Motor Phase Loss]
- Loss of one phase at drive output.
- Output contactor open.
- Motor not connected or motor power too low.
- Instantaneous instability in the motor current.
- Check the connections from the drive to the motor.
- If an output contactor is being used, set [Output Phase Loss] (OPL) to [Output cut] (OAC) ([FAULT MANAGEMENT] (FLt-) menu, page 94).
- Test on a low-power motor or without a motor: In factory settings mode, motor output phase loss detection is active ([Output Phase Loss] (OPL) = [Yes] (YES)). To check the drive in a test or maintenance environment without having to switch to a motor with the same rating as the drive (particularly useful in the case of high-power drives), deactivate motor phase loss detection ([Output Phase Loss] (OPL) = [No] (nO)).
- Check and optimize the [IR compensation] (UFr), [Rated motor volt.] (UnS), and [Rated mot. current] (nCr) parameters, and perform an [Auto tuning] (tUn) operation, page 43.

    OSF [Mains Overvoltage]
- Line voltage is too high.
- Disturbed line supply.
- Check the line voltage.

    PHF [Input Phase Loss]
- Drive incorrectly supplied or a fuse blown.
- Failure of one phase.
- Three-phase ATV312 used on a single-phase line supply.
- Unbalanced load.
- This protection only operates with the drive on load.
- Check the power connection and the fuses.
- Reset.
- Use a three-phase line supply.
- Disable the detection by setting [Input phase loss] (IPL) = [No] (nO) ([FAULT MANAGEMENT] (FLt-) menu, page 94).

     SLF [Modbus Fault]
- Interruption in communication on the Modbus bus.
- Remote display terminal enabled ([HMI command] (LCC) = [Yes] (YES), page 61) and terminal disconnected.
- Check the communication bus.
- Refer to the relevant product documentation.
- Check the link with the remote display terminal.

    CFF [INCORRECT CONFIGURATION]: The current configuration is inconsistent, possibly due to the addition or removal of an option. To resolve this, return to factory settings or retrieve a valid backup configuration using the [Restore config.] (FCS) parameter.
    CFI [INVALID CONFIGURATION]: The configuration loaded in the drive via the serial link is inconsistent. Check the previously loaded configuration and load a consistent one.
    USF [UNDERVOLTAGE]: This error is triggered by insufficient line supply, a transient voltage dip, or a damaged precharge resistor. Check the voltage and the voltage parameter settings. The tripping thresholds vary depending on the model:
- ATV312ppppM2: 160 V
- ATV312ppppM3: 160 V
- ATV312ppppN4: 300 V
- ATV312ppppS6: 430 V
- If the issue persists, replace the drive.

Additionally, the following fault detection codes are displayed on the ATV12 remote display terminal:

    InIt: Indicates that the microcontroller is initializing and searching for the communication configuration (COM.E).
    COM.E: A communication error due to a time-out fault detected (50 ms). This message is displayed after 20 attempts at communication.
    A-17: An alarm indicating that a button has been held down for more than 10 seconds, or the keypad is disconnected. The keypad wakes up when a button is pressed.
    cLr: Confirmation of a detected fault reset. This is displayed when the STOP button is pressed once during a remote terminal detected fault.
    dEU.E: Drive disparity error indicating that the drive brand does not match that of the remote terminal.
    rOM.E: ROM anomaly detected by the remote terminal based on checksum calculation.
    rAM.E: RAM anomaly detected by the remote terminal.
    CPU.E: Indicates other detected faults not specified.