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What would cause the Altivar ATV340 Process Drive to power up with STO on the display?

Issue:
Altivar Process Drive power up with Safe Torque Off on the display

Product Line:
ATV

Environment:
All

Cause:
Wiring

Resolution:
The VFD safety feature requires 24Vdc input on STOA and STOB terminals. If there is no field wiring to these terminals, you must leave or install a jumper from 24v to STOA / STOB on top of the drive in the CN2 position.