Search FAQs

You are currently viewing the content available in Vietnam. If you are looking for information for another region, please select the correct country from the top-left dropdown in the page and 'Navigate to Browse FAQs' in the Support menu.

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.