patient care

[n84jrnation]

I am wiring a patient care doctors office primarily physical therapy. i have a couple questions. one does lighting need a redundant ground. and second we ran 12-3-3 m/c home runs to junction boxes above the ceiling,does the redundant ground have to go back to the panel or just to the junction box.

 

[roger]

I am wiring a patient care doctors office primarily physical therapy. i have a couple questions. one does lighting need a redundant ground.

See Exception No 2 to (3) of 517.13(B)

and second we ran 12-3-3 m/c home runs to junction boxes above the ceiling,does the redundant ground have to go back to the panel or just to the junction box.

It will need to go back to the panelboard, just stopping a jbox doesn't mean much.

Roger

 

[GoldDigger]

Some will argue that it must go all the way to the service panel where the bonding jumper is located.

mobile

 

[iwire]

Some will argue that it must go all the way to the service panel where the bonding jumper is located.

mobile

We have to complicate things.

Well in that case it depends on there being a SDS involved or not.

 

[steve66]

Some will argue that it must go all the way to the service panel where the bonding jumper is located.

mobile

some would be wrong.

it says branch circuits, not feeders

 

[kwired]

517.13(B)(1) just says the wiring method itself must qualify as an EGC AND that an insulated EGC also must be run with the branch circuit conductors.

Branch circuit conductors end at the panelboard they originate in. As I see it that EGC supplying the panelboard can just be a metal metal raceway enclosing the panel feeder conductors.

 

[n84jrnation]

We have to complicate things.

Well in that case it depends on there being a SDS involved or not.

what is a SDS

 

[raider1]

what is a SDS

Separately Derived System.

Chris

 

[dkidd]

I am wiring a patient care doctors office primarily physical therapy. i have a couple questions. one does lighting need a redundant ground

If you were under 2017, you wouldn't. See http://ecmweb.com/nec/2017-national-electrical-code-changes?page=17

 

[roger]

If you were under 2017, you wouldn't. See http://ecmweb.com/nec/2017-national-electrical-code-changes?page=17

See post #2. Lighting above 7.5' has not required a wire type EGC for many code cycles.

Roger

 

[raider1]

If you were under 2017, you wouldn't. See http://ecmweb.com/nec/2017-national-electrical-code-changes?page=17

Provided that the lights are installed at least 7 1/2' above the floor and the switches are located outside the patient care vicinity.

Here is what Exception #3 states

Exception No. 3: Luminaires more than 2.3 m (71∕2 ft) above the foor
and switches located outside of the patient care vicinity shall be permit‐
ted to be connected to an equipment grounding return path complying
with 517.13(A) or (B).

I added the bold on the change in the exception.

Under the 2014 NEC that exception only allows compliance with 517.13 (A) so you could not use standard MC cable for the luminaires even if they were above 7 1/2'.

Chris