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ATV61 (or ATV71) is tripping on Ground short circuit (SCF3) fault.

Issue:
What is an SCF3 fault on the ATV61 and ATV71 drives?

Product Line:
Alitvar ATV61 and ATV71

Environment:
All

Cause:
Ground Short Circuit fault

Resolution:
Possible causes
1:) Short circuit or grounding at the drives output.
2:) Incorrect Motor nameplate parameters programmed in the drive.
2:) Significant earth leakage current at the drives output if several motors are connected in parallel.

Troubleshooting Tips. 
Tip 1: Check your grounding on the motor and to the output of the drive.
Tip 2: Verify that the correct motor nameplate information has been programmed.   In Menu 1.1 [Simply Start] or Menu.4 [Motor Control] ensure that the Motor Power, Motor Voltage, Motor Current, Motor Frequency and Motor Speed are correct.
Tip 3: Check to see if the drive will run open circuit without the motor connected to it.  Remove the motor leads, turn off the OPL in FLT menu.  Try running the drive at 20, 40 and 60hz.  At each voltage level check the output voltage with a true rms meter  on UVW to see if the voltages are balanced phase to phase.
Tip 4: Remove mains voltage L1 L2 L3  let the DC bus discharge until you have less than 24vdc on PA + and PC-. Now put your meter in diode mode.  Check PA to UVW with your meter you should read .3v in one direction and OL in reverse direction.   Repeat process on PC- to UVW.  Values outside of the given range could indicate an issue with one or more of the IGBT's or connections.

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