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Why does Altivar ATV56 or ATV666 keypad show DC Bus Too high when attempting to run the Autodiagnostics (Menu 8)

Diagnostics indicate the DC Bus Votlage is too high.

Product Line:
ATV66, ATV56

All part numbers, all models

Autodiagnostic menu can not be accessed with full voltage applied to the VFD.

In order to access the autodiagnostic menu, the customer can not have line power on the unit (L1, L2, and L3) but only control power power on CL1 & CL2.
CL1 and CL2 are nomally connected to the L1 and L2 terminals via jumpers, which may have to be removed.
Once line voltage is applied to CL1 and CL2 and removed from L1, L2, and L3 the DC Bus votlage should only be around 14VDC which is low enough for the Autodiagnostic tested to operate.
In most cases, it is best to document the actual fault or message that directed you to go to menu 8 and troubleshoot that rather than attempting to run the Autodiagnostic tests.

Note that these drives have been obsolete for more than 11 years.  

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