Borrowed ground

[Baumeister]

I have a 2 gang junction box in my basement ceiling, that has 2 hots entering. One is the old 2 wire Romex from the 60's, the other is modern 3 wire. I need to tie in to the old 2 wire, for a bathroom vent fan. (3 wire is maxed out) Is it ok to tap into the ground on the 3 wire, moving forward out of the box with 12/2 w ground ? 2017 NEC states in 250.130, "Acceptable Grounding" ( #4 ) "An equipment grounding conductor that is part of another branch circuit that originates from the enclosure where the branch circuit for the receptacle or branch circuit originates." Just looking for clarity on the rule. I don't really need a ground on the far end, at the fan and light. Neither are grounded inside the exhaust fan box. More curious than anything.

 

[mm08822]

When multiple cables enter the box, the grounds are tied together whether the cable(s) is supplying power into the box or receiving power from a connection made in the box. Tie into the existing grounds with your new cable tapping power from within the box.

Safer to have a ground than not.

Unless you have a plastic fan housing, there should be a means to ground the enclosure.

 

[wyliesdiesels]

yup good to go