Schneider Electric Altivar Machine ATV320 fault PHF: Input phase loss
PHF on a Schneider Altivar ATV320 is an input phase loss error: one supply phase is missing or the drive is wrongly supplied. Schneider notes this protection only operates with the drive on load.
Diagnose this with AI
Try Free Drive Diagnostic Upload a keypad photo, the fault history or a parameter export from your Schneider Electric Altivar Machine ATV320. InduQT compares the evidence and suggests the next useful checks.
When it happens
- While running on load
- After a fuse blows on one phase
- On a 3-phase drive fed from a single-phase supply
Likely causes and checks
1Blown fuse or open phase
- Points to it
- Sudden onset; one phase missing at the drive input.
- Check
- Measure all three input phases at the drive and check the fuses (locked out).
2Drive incorrectly supplied
- Points to it
- New installation or a 3-phase ATV320 on a single-phase supply.
- Check
- Confirm the supply matches the drive reference; use a 3-phase supply for a 3-phase drive.
3Loose input connection
- Points to it
- Intermittent PHF under load; warm terminal.
- Check
- Lock out and check terminal tightness and contactor contacts.
4Unbalanced load or supply
- Points to it
- All phases present but unequal.
- Check
- Measure phase voltages and currents under load.
Telling it apart
- PHF is one missing input phase; losing two or three phases lets the drive run on until it trips on USF.
- OPF1/OPF2 are output phase loss between drive and motor.
- PHF clears as soon as its cause disappears. Schneider documents [InPhaseLoss Assign] IPL = No to disable the detection; do not use that to mask a real lost phase.
Relevant parameters
| Parameter | Name | Why it matters |
|---|---|---|
| IPL | InPhaseLoss Assign | Input phase loss detection (3-phase drives). Leave it active unless the manual’s conditions apply. |
Evidence to collect
- Error history entry and mains voltage in the record
- Phase voltages at the drive input under load
- Fuse condition
- Drive reference vs supply type
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