ATV61 (ATV71) drive is tripping on DB unit sh. circuit fault (fault code bUF)
Issue:
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
Environment:
ATV61 or ATV71 drives without a DB (Dynamic Braking) Resistor or Braking Unit.
Cause:
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.
Resolution:
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.
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If this article does not answer your question, check out our FAQ database that has answers to more commonly asked questions: Frequently Asked Questions - Schneider Electric (se.com)
If this FAQ did not solve your issue, you can call us at 1-888-778-2733 Option 2 and then 4 or e-mail us at drive.products.support@se.com to create a case with our Technical Support Team.
If you are not located in North America, please contact your local Customer Care Center for assistance: Support | Schneider Electric Global (se.com)
Released for: Schneider Electric USA








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