Wire joints

[tomtooker]

An old question with many responses, at least out in the field. Are we allowed to make joints in panels?
For example: You have the same circuit leaving the panel in two seperate conduits. But to get only one wire on the circuit breaker, you need to tie the two conductors together with a pigtail to the breaker. Legal by NEC?

 

[roger]

Yes you can, see 312.8 and read the whole section.

As a side note, a number of breakers can have more than one wire landed on them.

Roger

 

[infinity]

Given the generous 75% cross sectional fill for splices you could try but you could probably never exceed the 75%.

 

[masterinbama]

Given the generous 75% cross sectional fill for splices you could try but you could probably never exceed the 75%.

I've seen some that I thought were close, yet the barely pushed 50%

 

[M4gery]

Are we allowed to make joints in panels? ~ An old question with many responses, at least out in the field.

I find this fact very disturbing. Just the other day I listened to a conversation between 2 old timers. The first mentioned to an apprentice how you can't splice inside a panel, the second old timer "corrected' the first by saying that you can splice inside an existing panel or panel upgrade but not a new panel in a new installation.

When I politely mentioned that you can splice in any panel barring the 75% fill they called BS on me, yet they weren't willing to let me show them the NEC article on my new fangled iPhone.

 

[Dennis Alwon]

I find this fact very disturbing. Just the other day I listened to a conversation between 2 old timers. The first mentioned to an apprentice how you can't splice inside a panel, the second old timer "corrected' the first by saying that you can splice inside an existing panel or panel upgrade but not a new panel in a new installation.

When I politely mentioned that you can splice in any panel barring the 75% fill they called BS on me, yet they weren't willing to let me show them the NEC article on my new fangled iPhone.

I remember back in 1974 or 1975 getting reminded by an inspector in upstate NY that splicing in the panel was non compliant. I wonder if it was a rule at one time.

 

[infinity]

I find this fact very disturbing. Just the other day I listened to a conversation between 2 old timers. The first mentioned to an apprentice how you can't splice inside a panel, the second old timer "corrected' the first by saying that you can splice inside an existing panel or panel upgrade but not a new panel in a new installation.

When I politely mentioned that you can splice in any panel barring the 75% fill they called BS on me, yet they weren't willing to let me show them the NEC article on my new fangled iPhone.

I've worked with some similar old timers, guys who last opened a code book when they were in apprentice school back in the 70's. Same guys who say you need a pull point every 100' of pipe. :roll:

 

[sii]

I've worked with some similar old timers, guys who last opened a code book when they were in apprentice school back in the 70's. Same guys who say you need a pull point every 100' of pipe. :roll:

They're right if you only have a 100' tape.:thumbsup:

 

[Stevareno]

The way I see it, you can't have it both ways. You either have to allow splices in the panel or you have to allow more than one wire connected to the breaker.
I've never had an inspector ding me for having wire nutted joints in the panel, but I have had them ding me for two wires on the breaker.

BTW, I don't really get why you can't have two wires on the breaker. For example, some breakers look like they are made to accept more than one wire, one on each side of the screw under the clamp. :?

 

[jumper]

The way I see it, you can't have it both ways. You either have to allow splices in the panel or you have to allow more than one wire connected to the breaker.
I've never had an inspector ding me for having wire nutted joints in the panel, but I have had them ding me for two wires on the breaker.

BTW, I don't really get why you can't have two wires on the breaker. For example, some breakers look like they are made to accept more than one wire, one on each side of the screw under the clamp. :?

Square D?

 

[roger]

BTW, I don't really get why you can't have two wires on the breaker. For example, some breakers look like they are made to accept more than one wire, one on each side of the screw under the clamp. :?

As I said in post #2, a number of breakers are listed for two conductors, SQ D QO's, SQ D Homeline, C-H are a few that are listed for two conductors, see 110.14(A)

Roger

 

[infinity]

This one surely looks like it can accommodate two conductors but I can't find anything in it's listing or labeling to say that it's permissible.

 

[readydave8]

I remember back in 1974 or 1975 getting reminded by an inspector in upstate NY that splicing in the panel was non compliant. I wonder if it was a rule at one time.

If I remember correctly NEC used to say no splice, then the exception said when it was ok. As others have said it would be hard to exceed 75% fill. I've worked around older electricians how would always bring power to lite and drop a switch loop because "its illegal to put a wire nut in a switch box"

So many tradespeople think they're doing things the right way because they're doing them the way they always done it.

 

[Sierrasparky]

If I remember correctly NEC used to say no splice, then the exception said when it was ok. As others have said it would be hard to exceed 75% fill. I've worked around older electricians how would always bring power to lite and drop a switch loop because "its illegal to put a wire nut in a switch box"

I suppose that was because they had used those small handy boxes and 12ga wire. I don't think they calc out for in and out or 4 wires.

So many tradespeople think they're doing things the right way because they're doing them the way they always done it.

It's pretty sad when they pass that miss information on to others I try not to myself but I have been misinformed in the past by some who felt they were the cats meow!

 

[stew]

If I remember correctly NEC used to say no splice, then the exception said when it was ok. As others have said it would be hard to exceed 75% fill. I've worked around older electricians how would always bring power to lite and drop a switch loop because "its illegal to put a wire nut in a switch box"

So many tradespeople think they're doing things the right way because they're doing them the way they always done it.

when was it ever non compliant? I dont think it has ever been non-compliant except in someones mind.

 

[Little Bill]

when was it ever non compliant? I dont think it has ever been non-compliant except in someones mind.

I think they get it from the first sentence of 312.8 and not reading the rest of the article.

312.8 Enclosures for Switches or Overcurrent Devices.
Enclosures for switches or overcurrent devices shall not be
used as junction boxes, auxiliary gutters, or raceways for conductors
feeding through or tapping off to other switches or
overcurrent devices, unless adequate space for this purpose is
provided. The conductors shall not fill the wiring space at any
cross section to more than 40 percent of the cross-sectional
area of the space, and the conductors, splices, and taps shall
not fill the wiring space at any cross section to more than
75 percent of the cross-sectional area of that space.

 

[infinity]

I think they get it from the first sentence of 312.8 and not reading the rest of the article.

312.8 Enclosures for Switches or Overcurrent Devices.
Enclosures for switches or overcurrent devices shall not be
used as junction boxes, auxiliary gutters, or raceways for conductors
feeding through or tapping off to other switches or
overcurrent devices, unless adequate space for this purpose is
provided. The conductors shall not fill the wiring space at any
cross section to more than 40 percent of the cross-sectional
area of the space, and the conductors, splices, and taps shall
not fill the wiring space at any cross section to more than
75 percent of the cross-sectional area of that space.

Many times that is the issue with this section. Roger correctly stated in his response to read the entire section for that very reason.

 

[masterinbama]

A lot of these misconceptions also stem from people that have always worked on projects with written job specifications.

I have had J-Men try to tell me that 1/2 EMT is only allowed for single drops in walls for switches and outlets (A NASA rule at MSFC here in Huntsville.)

 

[guschash]

The 2011 code changed 312.8 to " read shall be permitted......"

gus

 

[K8MHZ]

As I said in post #2, a number of breakers are listed for two conductors, SQ D QO's, SQ D Homeline, C-H are a few that are listed for two conductors, see 110.14(A)

Roger

The last C-H I did used breakers that only allowed for one conductor.