PGF / PGF1 PG (Encoder) Feedback Error fault in delta drive

PGF / PGF1 PG (Encoder) Feedback Error fault in delta drive troubleshooting

Description

For drives using closed-loop vector control with an encoder (PG card), PGF indicates a loss of feedback signal. The drive commands the motor to move but receives no pulse signal indicating movement, or the direction is reversed.

Causes

1. Disconnected Encoder: Loose wiring between the encoder and the PG option card.
2. Incorrect Phasing: The A and B channels are swapped, making the drive think the motor is spinning backward.
3. Broken Coupling: The encoder shaft coupling is broken; the motor spins, but the encoder does not.
4. PG Card Failure: The option card mounted on the drive is faulty.

Solution

Check the feedback loop:
1. Wiring Check: Verify A, B, Z, Power, and Ground connections. Shielding must be grounded to prevent noise.
2. Swap Channels: If the fault happens instantly upon start with high current, swap A and B wires.
3. Check Voltage: Ensure the encoder power supply (5V or 12V) is correct.
4. Open Loop Test: Switch the control mode to SVC (Sensorless Vector) or V/F. If the motor runs fine, the issue is strictly in the encoder/PG card system.