Ot / Ot1 Over-Torque Detection fault in delta drive

Ot / Ot1 Over-Torque Detection fault in delta drive troubleshooting

Description

The Ot fault is a user-configurable protection. Unlike Over-Current (which is hardware safety), Over-Torque is software-based. It triggers when the output current/torque exceeds a specific level (e.g., 120%) for a specific time (e.g., 5 seconds). It is essentially a "Mechanical Jam Pre-Warning."

Causes

1. Mechanical Binding: A conveyor belt is rubbing, a bearing is seizing, or a pump impeller is clogged with debris.
2. Process Change: The viscosity of the fluid being pumped has increased, or the load on the machine is heavier than designed.
3. Parameter Setting: The "Over-Torque Detection Level" is set too low (e.g., set to 80% when the machine normally runs at 90%).
4. Acceleration: The detection is enabled during acceleration, where high torque is naturally required.

Solution

Adjust logic or fix mechanics:
1. Inspect Load: Check the driven machine for resistance. Can you turn it by hand?
2. Adjust Parameters: Check Group 06 (Protection). Increase the "Over-Torque Detection Level" (e.g., to 150%) or increase the "Detection Time" (delay) to filter out momentary spikes.
3. Mode Change: You can change the behavior from "Fault and Stop" to "Continue Running with Warning" if the process is critical.
4. Check Gearbox: Low oil in a gearbox can cause gradual torque creep triggering Ot.