decel inhibit powerflex 70

[dclane1]

This is something we have been chasing for a while. After looking through all the forums and googling I was about to give up. Then I noticed something I should have seen right away!
Someone had probably thought they would tidy up a bit and Ty-wrapped all the wire nice and neat. Including the 480 vac with 10 vdc control. The 480 was messing up the drive frequency input causing it to excel/decel and then trip on decel inhibit. I separated the wires by power and all is working fine!

 

[GoldDigger]

Welcome to active participation in the Forum!
Thanks for sharing your discovery.
I wonder whether clean 480AC was enough to cause false signals or maybe there was noise on the 480 from the machinery it was feeding?
Was the 480V the power to the drive?

 

[Jraef]

Welcome to active participation in the Forum!
Thanks for sharing your discovery.
I wonder whether clean 480AC was enough to cause false signals or maybe there was noise on the 480 from the machinery it was feeding?
Was the 480V the power to the drive?

Output cables from the VFD to the motor would be my guess. That, or the 0-10VDC signal wire was not shielded.