[ceencee]

Hello all. Ive drawn up some prelim schematics.They are rough....i mean rough lol. I just want to check if im on the right path or not. If you see anything that wont work or is simpler please dont hesitate to tell me, im still learning.

Thanks
Wade

[Al_The_Man]

Normally you would see a contactor in the VFD feed and also on the primary side of any servo transformer, these together with the motor contactors would be dropped out via a hardwired E-Stop.
The power supply for the coils for these contactors would be fed through a contact on the E-stop or Control relay.
Also if any PLC is used, the power to the outputs is dropped out via the same relay, the inputs and any controller can stay energized.
Al.

[ceencee]

Thanks Al. I was looking over some drawings of e-stop switches because i have 3 to put in.They looked like they were in the controller/relay circuits like you were stating. Would there not be an actual power disconnect to get a category 0 Emergency stop, Or would have all the contactors kick off be good enough?
If there is a contactor on the VFD....is it energized when ever the spindles are energized or is it energized once and the controls for it then are used?

thanks
wade

[Al_The_Man]

VFD's have low level logic inputs for fwd/rev etc. and generally the contactor is enabled and stays picked up with the E-stop relay.
Now in a typical commercial machine the control voltage is 24vdc, If you set up a dedicated E-stop series string the 24v relay contact would switch supply to the contactor coils.
The NFPA79 usually has some typical schematics you can use for a guide.
Al.