Quote Originally Posted by mactec54 View Post
Not correct on this VFD Drive when you switch a Relay on there is no voltage at the output of the relay to switch the VFD Drive On/ Off or to change the Direction there is no voltage in the switching if there is he has a problem

I think you are confused with the PWM signal with is what changes the speed of the spindle this has nothing to do with how the spindle motor will start M3 M4 and M5

So if he has a Voltage at the VFD Drive Terminals for FWD / REV then he has a problem if so this will damage the VFD Drive that he has
Usually the inputs are active low and pulled up to the internal 10V, 12V or 24V inside the VFD, so he can measure voltage between the Digital Ground and the input when the relay is open (off) or when it is not even connected.
When he switches the relay then he should measure 0Volts as he should switch the 0Volts to it.