Err 12.0 Over-voltage protection fault in panasonic drive

Cause: DC bus voltage exceeded the limit (approx. 400VDC). Caused by high input voltage, regenerative energy from braking, or a disconnected braking resistor.

Remedy:

• Measure input voltage (L1, L2, L3) to ensure it is within range.
• Check if the external braking resistor is disconnected or open (measure resistance between B1-B2).
• Remove any phase-advancing capacitors (power factor correction) from the input line.
• Increase deceleration time (Pr0.03) to reduce regenerative energy.