several EGC in a box

[Ponchik]

If there is a single EMT conduit from a 5" square J-box that has circuits going to Oven, fridge, microwave and cooktop and we are using the EMT as an EGC, and into this box are the circuits that come from the panel but are in NM cable. (1) 10/3 for the oven and (1) 10-3 for the cooktop, (2) 12-2 for the microwave and fridge. My question is do all of the EGC have to be connected together in the 5s J box? Obviously a #10 will bond to the 5s-J box.

Thank you.

 

[Gac66610]

IMO yes, if you are using EMT as ground and you leave it (through j box) where is the NM getting its ground?

hope i read that right

 

[1793]

I would look at 250.148 and see if this answers your question.

 

[Gac66610]

i did not read it right the first time, i would NOT think so, just the #10 bond to jbox

 

[Ponchik]

IMO yes, if you are using EMT as ground and you leave it (through j box) where is the NM getting its ground?

hope i read that right

all NM cable originate from the panel and end up in the J box, of course in the panel the EGC are terminated on the grounding bar.

 

[Smart $]

... do all of the EGC have to be connected together in the 5s J box?

Since you are changing wiring methods, it goes hand-in-hand that you are splicing your circuit conductors. 250.148 was already mentioned and is the correct section regarding this matter.

The simple answer is: yes.

 

[hillbilly1]

So the nm is pulled in the emt? Must be a pretty deep box for all of that!

 

[Ponchik]

So the nm is pulled in the emt? Must be a pretty deep box for all of that!

the NM is not in the EMT. the EMT contains single conductors and the NM comes from the panel to the 5s j box.

 

[Ponchik]

The simple answer is: yes.

besides Because the code says, why do they have to be connected together. Safety, functionality...

 

[Smart $]

besides Because the code says, why do they have to be connected together. Safety, functionality...

...continuity, ... all of the above

Besides, if you didn't connect them together, what would you do with them in your case?

 

[jumper]

What if all 4 circuits were faulted (unlikely but possible)?

You would want all the available EGCs to help them clear.

 

[Ponchik]

Besides, if you didn't connect them together, what would you do with them in your case

Just leave them in the box.

I know it doesn't take anymore time to connect them all together, but i was just wondering if there is any other issues besides the code.

 

[jumper]

Er,faults. Post#11

 

[hillbilly1]

all NM cable originate from the panel and end up in the J box, of course in the panel the EGC are terminated on the grounding bar.

So the nm is pulled in the emt? Must be a pretty deep box for all of that!

That quote is where I misunderstood where you said "all NM cable originate from the panel and end up in the J box" as to the answer to your question I would say yes, they all would terminate together to the bond jumper if your using the emt as the EGC, or if a separate EGC is pulled in the conduit (you need only one, sized for the largest ocp) all tied to it.

 

[Smart $]

Just leave them in the box...

I understand that "can" be done, but it has to be out of sheer ignorance? Sorry, to be blunt about it... but this is a very serious matter? How does one justify the wires' existence? Any chance you could just leave the other wires in the box and have the equipment function properly? Is there not equipment on both ends of that circuit? Why do you think the wires are there to begin with? How can you know the EMT can be used as the EGC, yet think to just leave the NM grounds in the box???

 

[Ponchik]

I understand that "can" be done, but it has to be out of sheer ignorance? Sorry, to be blunt about it... but this is a very serious matter? I agree this is serious How does one justify the wires' existence? Any chance you could just leave the other wires in the box and have the equipment function properly? Is there not equipment on both ends of that circuit? One end if the panel the other end if the appliance, Why do you think the wires are there to begin with? For safety How can you know the EMT can be used as the EGC, I don't know because it is existing and buried in the attic yet think to just leave the NM grounds in the box??? the NM cables do not go in the conduit, connecting all of NM grounds together is not going to make a bit of difference if in the attic the EMT conduit is broken because the NM cables do not go in the EMT conduit

I agree sometimes one has to be blunt but I know what the purpose of the EGC and why wires are installed and furthermore agree that the EMT may not be relied on as an EGC.

maybe i didn't explain the situation clearly. The existing conduit with single conductors was from the panel to the loads that i had mention in my OP without an EGC. So when the panel was upgraded the existing conduit couldn't be bent in the wall to enter the new panel, so it was cut and a junction box installed, then that box was fed with NM cable (the NM cable originates from the panel).

So theoretically instead of the NM cables i could have installed EMT to the Jbox without any EGC. So between the panel and the J box, what is the difference between the EMT acting as my EGC vs only one of the EGC from the NM cable?

I hope this is clear.

 

[kwired]

What if all 4 circuits were faulted (unlikely but possible)?

You would want all the available EGCs to help them clear.

If he had 4 circuits all in same raceway there only needs to be one EGC and it only needs sized to largest overcurrent device protecting conductors in that raceway. Now he has replaced the raceway with 4 separate cables - each with its own EGC. Similar yet different - does each EGC need to be connected even though effectively one would work? I think that is the question the OP is asking. I have not always connected all of them myself when they go to same point on each end, doesn't mean that it was right though.

I agree sometimes one has to be blunt but I know what the purpose of the EGC and why wires are installed and furthermore agree that the EMT may not be relied on as an EGC.

maybe i didn't explain the situation clearly. The existing conduit with single conductors was from the panel to the loads that i had mention in my OP without an EGC. So when the panel was upgraded the existing conduit couldn't be bent in the wall to enter the new panel, so it was cut and a junction box installed, then that box was fed with NM cable (the NM cable originates from the panel).

So theoretically instead of the NM cables i could have installed EMT to the Jbox without any EGC. So between the panel and the J box, what is the difference between the EMT acting as my EGC vs only one of the EGC from the NM cable?

I hope this is clear.

I was wondering why you had multiple NM cables and then transition to a raceway - usually it is raceway transitioning to cable methods.

 

[guschash]

I think as long as the #10 is connected in the j-box, the continuity between the emt and the #10 to the panel meets the requirement of 250.148 is meant.

 

[Smart $]

I agree sometimes one has to be blunt...

I commend you for not taking insult by it (or at least not appearing to), and persuing the issue diligently.

maybe i didn't explain the situation clearly. ...

So theoretically instead of the NM cables i could have installed EMT to the Jbox without any EGC. So between the panel and the J box, what is the difference between the EMT acting as my EGC vs only one of the EGC from the NM cable?

I hope this is clear.

Clearer... but for the purpose, it was clear to me before.

Actually, I've heard from other posts on using conduits as an EGC, EMT (properly installed and maintained) is a better EGC than a single #10 copper wire. Because it is in essence redundant grounding, the code allows a single EGC run in a conduit with multiple circuits. Nevertheless, a single #10 in a non-metallic wiring method is not equivalent to just EMT, and definitely not equivalent to EMT with an EGC.

On the code side of the issue, 330.3(B) general applies. Subsections (1) through (4) do not alleviate the general requirement in your case.

(B) Conductors of the Same Circuit. All conductors of
the same circuit and, where used, the grounded conductor
and all equipment grounding conductors and bonding conductors
shall be contained within the same raceway, auxiliary
gutter, cable tray, cablebus assembly, trench, cable, or
cord, unless otherwise permitted in accordance with
300.3(B)(1) through (B)(4).

I believe the requirement assumes the conductors to be properly terminated at each end :slaphead: