Cause : DC Bus Overvolt comes when the main circuit DC voltage exceeded the overvoltage detection level.

200-240 V Class: Approx. 410 V 380-480 V Class: Approx. 820 V (E1-01 greater than or equal to 400 V) Approx. 720 V (E1-01 < 400 V)

1. The deceleration time is too short and the regenerative energy from the motor is too large. Increase the deceleration time or connect a braking resistor (or Braking Resistor Unit). Alternatively, enable (set to 1) the stall prevention selection during deceleration (L3-04).
2. Motor ground fault (Ground fault current flowed to the capacitor in the control circuit of the Inverter through the power supply.) Check the output cable, relay terminal, or motor terminal box and correct the cause of ground fault.
3. Incorrect constant setting for speed search (The speed search can be performed during momentary power loss recovery and auto restart after a fault.)
   • Use the speed search function.
   • Adjust the settings of the Speed search operating current (b3-02) and Speed search deceleration time (b3-03).
   • Use the estimated speed search function. (Autotuning for motor line-to-line resistance is required.)Improper PG cable connection (PG noise, PG disconnection)
4. Check to see if the PG cable is connected properly.
5. The regenerative energy when an over- shoot occurs after acceleration is completed is too large. In vector control, enable (set to 1) the overvoltage inhibit selection (L3-11).
6. The power supply voltage is too high. Decrease the voltage so it’s within specifications.