Quote Originally Posted by cropwell View Post
This is why I asked about braking resistors
I've done a bit of googling of HY VFDs and braking resistors and there doesn't seem to be much folk wisdom out there. Plenty on how to make it spin up but very little on how to stop it again. The standard HY stop mechanism (if you just remove "run" signal) is to run down from current frequency to some pre-defined stop frequency at a rate given by a specified parameter, and then either coast to a stop or use "DC braking" according to another parameter. I can't find any specific description of how emergency braking works, but I haven't been through the manual word by word yet. I would have expected "cut power to motor and use DC braking", but in any case it sounds like there is a need for an external braking resistor. The manual does give recommended values for this, and it looks as if they are available from eBay or AliExpress for £20 or so.