BCS 462 grounding

[Bensiff]

I've read many times to ground the BCS controller to AC ground. Is this to mean the AC ground and DC negative are common and can share the same rail, or is this grounding the BCS controllers chassis to AC ground and keeping DC negative isolated?

 

[poptarts]

This is how I understand it works, you can see the optional ground going from BCS to the AC Ground block.

 

[crane]

Is this to mean the AC ground and DC negative are common and can share the same rail

Yes this one. Grounding the BCS case shouldn't be needed.