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iwire

Moderator
Staff member
Location
Massachusetts
The EMT already does that.

Yes, but a wire EGC was run so it must be used and of the correct size.

Call it redundant if you want but the NEC does not force you to run a wire EGC when you run EMT. (Excluding a hospitals and maybe pools.)
 

jap

Senior Member
Occupation
Electrician
Yes, but a wire EGC was run so it must be used and of the correct size.

Call it redundant if you want but the NEC does not force you to run a wire EGC when you run EMT. (Excluding a hospitals and maybe pools.)

True,

The rule seems to apply only if you splice.
I'm trying to get at what difference making a splice in the circuit conductors has.

JAP>
 

jap

Senior Member
Occupation
Electrician
Its a bid deal with everyone, they just dont talk about it, and when they do, they honestly dont know why they have to do it either....:)

I need to understand why we're having to do it, other than being called out for it if we dont, when it doesnt make complete sense at all.

The box in the graphic is like an 8x8x4 Screw Cover J-box or the like.

What am I ever going to put in that that needs me to bond to the box, or , that I cant do later if that time ever comes?

JAP>
 

kwired

Electron manager
Location
NE Nebraska
It isn't just that the box needs to be bonded if there is splices in any of the conductors, say that was a PVC box and you had several entries with splices in conductors from all raceway entries -you would have to join all the EGC's together AFAIK.
 

iwire

Moderator
Staff member
Location
Massachusetts
Its a bid deal with everyone, they just dont talk about it, and when they do, they honestly dont know why they have to do it either....:)

I don't think so. :)


I need to understand why we're having to do it, other than being called out for it if we dont, when it doesnt make complete sense at all.

The box in the graphic is like an 8x8x4 Screw Cover J-box or the like.

What am I ever going to put in that that needs me to bond to the box, or , that I cant do later if that time ever comes?

JAP>

What does the future have to do with it? When you choose to run a wire EGC it must be connected to the enclosures, panel tubs, disconnect switches etc

Remember, running the wire EGC was a choice made not by code, but by the installer or designer and once that choice is made you must use it.
 

jap

Senior Member
Occupation
Electrician
I don't think so. :)




What does the future have to do with it? When you choose to run a wire EGC it must be connected to the enclosures, panel tubs, disconnect switches etc

Remember, running the wire EGC was a choice made not by code, but by the installer or designer and once that choice is made you must use it.

The graphic indicates you dont have to connect to the enclosure unless a splice is made.
If there were no splices in the box evidently you wouldnt have to bond to the box.
Which is not a "Must" that you have to connect to the enclosure just because you have an equipment grounding conductor in it.
So what does the Splice have to do with it?

JAP>
 

jap

Senior Member
Occupation
Electrician
Are they afraid a wirenut will mysteriously fall off and they want a redundant return path other than the EMT that already bonds the box.

What does having a splice or not having a splice in the box have to do with having to bond to the box other than that scenario?


JAP>
 

ActionDave

Chief Moderator
Staff member
Location
Durango, CO, 10 h 20 min from the winged horses.
Occupation
Licensed Electrician
Are they afraid a wirenut will mysteriously fall off and they want a redundant return path other than the EMT that already bonds the box.

What does having a splice or not having a splice in the box have to do with having to bond to the box other than that scenario?


JAP>
I agree. The rule makes little sense to me also. The only thing I can figure is someone was aware how bad the Green to Everything crowd is at making sure their conduit connectors and couplings are done right that they worked very hard to get this adopted into the code to make things safe for everybody that comes along after one of their installs.
 

iwire

Moderator
Staff member
Location
Massachusetts
I agree. The rule makes little sense to me also.

I have no idea how or why this is such a point of contention.

The rule is simple, bond the box to the wire EGC, how is that hard to understand the reason?

Then they give us a break with the exception saying if you have not spliced or terminated the wires in that box you do not have to do so.

This is a huge break when you pull straight through a box without leaving a loop, think about this with large feeders and how difficult it would be to pull a loop in just the EGC of a 200 amp feeder in the middle of a long run.


But you guys can keep wondering about it while I keep on wiring. :D
 

ActionDave

Chief Moderator
Staff member
Location
Durango, CO, 10 h 20 min from the winged horses.
Occupation
Licensed Electrician
I have no idea how or why this is such a point of contention.

The rule is simple, bond the box to the wire EGC, how is that hard to understand the reason?
I understand what it says. I don't understand why it's there.

Then they give us a break with the exception saying if you have not spliced or terminated the wires in that box you do not have to do so.

This is a huge break when you pull straight through a box without leaving a loop, think about this with large feeders and how difficult it would be to pull a loop in just the EGC of a 200 amp feeder in the middle of a long run.
What evil mojo is released if you break the EGC and then splice it back together without bonding it to the box?
What happens to electrons flowing on the EGC during a fault when they come to a splice that is not bonded to the box? Do they stop and demand they are not going any further until some comes and adds a jumper wire?

But you guys can keep wondering about it while I keep on wiring. :D
I trust you will till I see a "d" added to the end of your handle.:p
 

iwire

Moderator
Staff member
Location
Massachusetts
What happens to electrons flowing on the EGC during a fault when they come to a splice that is not bonded to the box? Do they stop and demand they are not going any further until some comes and adds a jumper wire?

None.

Your right, we should run wire EGCs and not connect them to anything, that would make much more sense. :lol:
 

kwired

Electron manager
Location
NE Nebraska
If we pull through a conduit body we usually don't make any splices in any conductors, maybe the rules in a pull box with no splices is somehow based on that?

If you do make splices where permitted in a conduit body do you have to bond the EGC to the body (where metallic of course)?
 

jap

Senior Member
Occupation
Electrician
I have no idea how or why this is such a point of contention.

The rule is simple, bond the box to the wire EGC, how is that hard to understand the reason?

Then they give us a break with the exception saying if you have not spliced or terminated the wires in that box you do not have to do so.

This is a huge break when you pull straight through a box without leaving a loop, think about this with large feeders and how difficult it would be to pull a loop in just the EGC of a 200 amp feeder in the middle of a long run.


But you guys can keep wondering about it while I keep on wiring. :D

Your explanation above is a perfect example of why it seems pointless to have to bond to the box just because of a splice.

If it's necessary then lets do it.

Not,"You dont have to if it's not convienient" (Which is the confusing part).

That'd be like saying,,," Son you be home by 10",,,,, but,,,, "If your having fun, go ahead and stay out a little later".,,,,, :)

JAP>
 

jap

Senior Member
Occupation
Electrician
All I'm saying is that a splice should not determine whether or not the box needs to be bonded.

That determination should be made by the characteristics of the box and what other means may already be in place to bond the box.

An unbonded box that has circuit conductors passing through it unspliced is very dangerous.

I was in a chicken house one time that had a 4sq metal box mounted on a wooden post with wires running straight through it without a splice.
The box was not bonded yet one of the conductors had rubbed into the metal box.
I got between it and a metal cold water pipe and damned near bit my tongue in half before I could get away from it.

Probably not the greatest example, but, not having a splice in the box should not be an "OUT" for not having to bond the box.

The rule should probably read, "Conductors can pass through a box without having to bond the EGC to the box as long as the box is bonded by another acceptable means".
if a splice is made in the box, and the box is not bonded by another acceptable means, a bond must be made to the box.

Maybe, that's technically the way it already reads and the wording is just throwing me off. :)


JAP>
 

jap

Senior Member
Occupation
Electrician
If we pull through a conduit body we usually don't make any splices in any conductors, maybe the rules in a pull box with no splices is somehow based on that?

If you do make splices where permitted in a conduit body do you have to bond the EGC to the body (where metallic of course)?

If that conductive LB doesnt have another means to return a fault current,,, I feel it should be requred to be bonded somehow also.
But that's just me.

JAP>
 

kwired

Electron manager
Location
NE Nebraska
All I'm saying is that a splice should not determine whether or not the box needs to be bonded.

That determination should be made by the characteristics of the box and what other means may already be in place to bond the box.

An unbonded box that has circuit conductors passing through it unspliced is very dangerous.

I was in a chicken house one time that had a 4sq metal box mounted on a wooden post with wires running straight through it without a splice.
The box was not bonded yet one of the conductors had rubbed into the metal box.
I got between it and a metal cold water pipe and damned near bit my tongue in half before I could get away from it.

Probably not the greatest example, but, not having a splice in the box should not be an "OUT" for not having to bond the box.

The rule should probably read, "Conductors can pass through a box without having to bond the EGC to the box as long as the box is bonded by another acceptable means".
if a splice is made in the box, and the box is not bonded by another acceptable means, a bond must be made to the box.

Maybe, that's technically the way it already reads and the wording is just throwing me off. :)


JAP>

If that metallic box is isolated (as in has no metal raceway or other method of bonding it) it will need bonded to the EGC regardless if any other conductors are spliced within the box. Did not look it up but pretty sure this is require to be bonded by a different section then the portion that allows us to pass through when no other splices are made.
 
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