This was posted on Mike Holt’s news letter;
210.4 Multiwire Branch Circuits.
(B) Disconnecting Means. Each multiwire branch circuit must have a means to simultaneously disconnect all ungrounded conductors at the point where the branch circuit originates.
Can someone explain to me why this is called ungrounded conductors when the grounds and neutrals are hooked up?
Confused Confusious. ;)