The "PHAS input PHASE LOSS" fault on your Parker AC890 drive indicates that the drive has detected a loss of one or more of the input AC power phases. This is a critical fault as the drive is designed to operate with a balanced three-phase (or sometimes single-phase, depending on the model and configuration) input supply.
Troubleshooting Steps:
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Check Incoming Power Supply:
- Measure Voltages: Use a multimeter to carefully measure the AC voltage between each pair of input terminals (L1-L2, L2-L3, L3-L1) at the drive's input. You should have a balanced three-phase voltage (or the correct single-phase voltage if applicable) present. If one or more phases show zero or significantly lower voltage, the problem is upstream of the drive.
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Inspect Drive Input Terminals: Ensure that all the power input wires are securely connected to the correct terminals on the drive. Tighten any loose screws.
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Verify Input Contactor/Switch: If there's a contactor or switch, check its operation. Ensure all poles are closing correctly and providing continuity.
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Check Drive Parameters (if possible): Some drives have parameters related to phase loss detection sensitivity. Consult the AC890 drive manual to see if there are any relevant settings that might need adjustment (though this is less likely to be the root cause of a hard phase loss).
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Power Cycle the Drive: Turn off the main power supply to the drive, wait a few minutes, and then turn it back on. This might clear a temporary error, but if a phase is genuinely missing, the fault will likely reappear.
