Brake chopper short-circuited

What does 27 mean?

The internal brake transistor (chopper) within the drive, which is responsible for switching the brake resistor, has short-circuited. This renders the regenerative brake function inoperative and can cause immediate faults or damage if the drive attempts to use it.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Contact Danfoss service or a qualified technician for further diagnosis, repair, or replacement of the drive unit.

2. 4

   Ensure any connected brake resistor is also checked for faults, as external issues can sometimes lead to chopper failure.