3 phase motor runs slow.

[JST]

................

Sounds like your cheap VFD is no good. There's a reason they are verboten for discussion here

Part of that rule is that there is no reason why we should go to trouble to provide the product support that the makers do not bother to. Also that it often takes a good deal of interpretation of "chinglish" to understand what the manual ought to say.

No reason to provide that service to a cheap vendor from a place that hates us.

 

[rons]

Any ideas what I should check?

Reset the VFD parameter bank back to the factory defaults.
Make a note of what your relevant parameters like hp, amp.
Then do a VFD auto tune function.
See if any parameters changed from the factory defaults.

Or you could manually change parameters.

I would look at the "current limit" parameter.