ATV61 (ATV71) drive is tripping on DB unit sh. circuit fault (fault code bUF)


11 March 2022

ATV61 or ATV71 - getting DB unit sh. circuit fault (bUF)

Product Line:
ATV61 drives. 
230V - ATV61HD55M3X and larger
460V - ATV61HD90N4 and larger
600V - ATV61HC11Y and larger

ATV71 drives. 
230V - ATV71HD55M3X and larger
460V - ATV71HD90N4 and larger
600V - ATV71HC11Y and larger

ATV61 or ATV71 drives without a DB (Dynamic Braking) Resistor or Braking Unit.

Short circuit in DB Braking Module, Shorted Braking Resistor, Short to Ground
The drives factory default is with the [Brake res. fault Mgt] set to Freewheel.

If a Dynamic Braking module and/or DB Resistor is installed, check for short circuit or overheating issues.

If Dynamic Braking is not being used;

Go to Menu 1.8 [Fault Management] and scroll to [BU Protection].
Change [Brake res. fault Mgt] from Freewheel (default setting) to Ignore.

This configuration is to be used only if there is NO braking unit or resistor connected to the drive.