8256
Category: Alarm
Cause
- The main circuit power supply is unstable or loses power
- Momentary power failure
- Supply voltage drops during operation
- Phase loss: A drive requiring a 3-phase supply is actually operating from a single-phase supply
- Servo drive fault
Corrective action
1/2. Check the drive input power specifications. Measure whether the input voltages at the non-drive side and drive side (L1 L2) of the main circuit cable meet the following specifications:
220V drive:
RMS value: 220V-240V; permissible deviation: -10%+10%(198V264V). Measure all three phases. Increase the power supply capacity.
3. Monitor the drive input voltage and check whether too much other equipment has been switched on using the same main circuit supply, causing insufficient capacity and a voltage drop. Increase the power supply capacity.
4. Check whether the main circuit wiring is correct and secure, and whether phase-loss fault detection parameter 200A-01h is masked. Replace the cable and correctly connect the main circuit power wires: Three-phase: R S T
5. Observe whether parameter 200B-1Bh (DC bus voltage) is in the following range:
220V drive: 200B-1Bh＜ 200V. If the fault is still reported after repeatedly turning off power and reconnecting the main circuit power (L1 L2), replace the servo drive.