Braking Transistor Overload Fault
Yaskawa · V1000 AC Drive
What does boL mean?
The internal braking transistor is experiencing an overload, typically due to a high regeneration power or an excessive repetition frequency during braking cycles. This can also trigger if the transistor's protective function is enabled incorrectly while a regenerative converter is present, or if the transistor itself is faulty. Prolonged overload can lead to component damage and potential drive failure.
Complete Troubleshooting Guide
- 1
Evaluate the application's braking energy requirements; consider installing an external regenerative converter if the duty cycle is high.
- 2
Increase the deceleration time parameter in the drive to reduce the energy dissipated through the braking transistor.
- 3
If a regenerative converter is installed, set parameter L8-55 (Internal DB Transistor Protection Selection) to '0' (Disable).
- 4
If the fault persists after performing the above steps, the internal braking transistor may be damaged, requiring replacement of the drive unit.