AF / AfE PID Feedback Error fault in delta drive

AF / AfE PID Feedback Error fault in delta drive troubleshooting

Description

When running in PID mode (e.g., constant pressure water boosting), the drive expects a feedback signal from a sensor. AfE triggers if the feedback signal goes wildly out of range or logic implies a disconnect (e.g., signal is 0V/0mA when the system is running full speed).

Causes

1. Sensor Disconnect: The pressure/flow sensor wire is broken.
2. Reverse Logic: The motor is running, but the pressure is dropping. This might mean the pipe burst or the pump is spinning backward.
3. Detection Time: The system takes too long to build pressure, exceeding the "Feedback Check Time" set in the drive.
4. Gain Settings: PID gains are unstable, causing oscillation that triggers error bounds.

Solution

Check the loop:
1. Sensor Check: Verify voltage/current at the AVI/ACI terminal matches the actual pressure gauge.
2. Motor Direction: Ensure the pump is building pressure. If the motor runs but pressure stays zero, check priming or rotation direction.
3. Adjust Timeout: Increase the "PID Feedback Error Detection Time." A large system fills pipes slowly; give it more time before tripping.
4. Check Leakage: A massive leak in the plumbing will prevent pressure buildup, causing the drive to think the sensor is broken.