ground wire clockwise around ground screws

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K8MHZ

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Michigan. It's a beautiful peninsula, I've looked
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Electrician
View attachment 7203

310.10(H)(2) Conductor Characteristics. The paralleled conductors
in each phase, polarity, neutral, grounded circuit conductor,
equipment grounding conductor, or equipment bonding
jumper shall comply with all of the following:
(1) Be the same length
(2) Consist of the same conductor material
(3) Be the same size in circular mil area
(4) Have the same insulation type
(5) Be terminated in the same manner

Aren't they paralleled in the box? Yes!

First attempt at drawing.

I don't see any parallel conductors (electrically joined at both ends) in your picture, nor have I ever put one in a residence.

If you think that your drawing indicates the presence of an NEC defined parallel conductor, we obviously were taught differently.
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
I don't see any parallel conductors (electrically joined at both ends) in your picture, nor have I ever put one in a residence.

If you think that your drawing indicates the presence of an NEC defined parallel conductor, we obviously were taught differently.

Correct paralleled does not apply here. :ashamed1:
 

K8MHZ

Senior Member
Location
Michigan. It's a beautiful peninsula, I've looked
Occupation
Electrician
?Terminals ? Product terminals, including wire connectors and terminal screws, are acceptable for connection of only one conductor, unless there is marking or a wiring diagram indicating the number of conductors which may be connected.? - UL

http://www.iaei.org/magazine/2006/1...ipment-is-marked-otherwise-however-i-cant-fi/

Does a single conductor become two if it's looped?

I would say that it is still a single conductor.

I know you are working hard to find a legitimate rule against looping, but I don't think you are going to find one in the NEC. The UL is a book of standards as well, but unless the jurisdiction you are working for has officially adopted the UL as law, it really doesn't mean much.

The sucky part about being a strict inspector is having to live with stuff that you consider sub standard but is still within the scope of the BARE MINIMUM rules.

An installation that follows the NEC to the letter is the worst installation allowed by law and you, as an inspector, are bound to the law, not to your own personal standards.

I hate back stabbed receptacles. Having (as an inspector) to allow them in a residence would make me ill, but I would have to do it.

I do admire your passion. I can see that you like a challenge and aren't afraid to do some leg work to back up your sentiments. But after a fashion it's going to look like you are grasping at straws.

I would like to know if this converstation is strictly acedemic, or have you actually gigged someone for looping a wire?
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
?Terminals ? Product terminals, including wire connectors and terminal screws, are acceptable for connection of only one conductor, unless there is marking or a wiring diagram indicating the number of conductors which may be connected.? - UL

Are you claiming that a looped conductor is actually more than a single conductor?

The UL498 testing requirements for wire-binding screw terminations includes; wrapping the conductor 2/3 - 3/4 of the way around the screw.
3/4 of the way around a circle, sure sounds like a 270? U-shape.

So as long as you do not form a complete circle with your looped conductor, you should be able to install it per UL testing procedures
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
Are you claiming that a looped conductor is actually more than a single conductor?

The UL498 testing requirements for wire-binding screw terminations includes; wrapping the conductor 2/3 - 3/4 of the way around the screw.
3/4 of the way around a circle, sure sounds like a 270? U-shape.

So as long as you do not form a complete circle with your looped conductor, you should be able to install it per UL testing procedures

Yes. It is more than one conductor. It is one wire but two conductors. Just like if you took a gec to ground rod #1 then to ground rod #2. The second section of that example makes it a bonding jumper not a gec.

Should be allowed and ARE allowed are two different things. :cool:

Edit: Where did you come up with the complete circle?
 
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jim dungar

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Location
Wisconsin
Occupation
PE (Retired) - Power Systems
Yes. It is more than one conductor. It is one wire but two conductors. Just like if you took a gec to ground rod #1 then to ground rod #2. The second section of that example makes it a bonding jumper not a gec.

Should be allowed and ARE allowed are two different things. :cool:

Edit: Where did you come up with the complete circle?

Have you actually read the UL 498 standard for attachment plugs and receptacles?
As I stated above; their test allows for a conductor to be wrapped 3/4 of the way around a screw. That means a wire-binding screw type terminal must accept a u-shaped conductor.
They do not mention clock-wise or counter-clock-wise. While they do mention removing insulation they do not mention length.

Where are you getting the definition of conductor and wire? Definitely not from Article 100 nor from Article 250.2 definitions.

250.30(A)6(c) talks about tapping off of a common electrode conductor, it does not refer to multiple 'common electrode conductors'.

According to your method of counting the number of conductors by the function they serve, it would not be code compliant to use 'acorn clamps' to connect a primary and supplemental ground rods together with a single wire because the clamps are rated for only one conductor.
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
Have you actually read the UL 498 standard for attachment plugs and receptacles?
As I stated above; their test allows for a conductor to be wrapped 3/4 of the way around a screw. That means a wire-binding screw type terminal must accept a u-shaped conductor.
They do not mention clock-wise or counter-clock-wise. While they do mention removing insulation they do not mention length.

Where are you getting the definition of conductor and wire? Definitely not from Article 100 nor from Article 250.2 definitions.

250.30(A)6(c) talks about tapping off of a common electrode conductor, it does not refer to multiple 'common electrode conductors'.

According to your method of counting the number of conductors by the function they serve, it would not be code compliant to use 'acorn clamps' to connect a primary and supplemental ground rods together with a single wire because the clamps are rated for only one conductor.

Nice try. It can be debated as to where the GEC changes from a GEC to a bonding jumper past the 'screw' but the acorn is rated for that single conductor. The screw on the device is rated for one conductor 'terminating' on it. I also doubt if that connection is rated for feed-through loop.

Think about what happens under a heavy current draw if your 'looped wire' is to close to itself? Arcing come to mind?
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
Nice try. It can be debated as to where the GEC changes from a GEC to a bonding jumper past the 'screw' but the acorn is rated for that single conductor.

What single conductor. You are the one that stated this is two conductors, a GEC and a jumper.

The screw on the device is rated for one conductor 'terminating' on it.
Termination, as you seem to be describing it (i.e. end as opposed to connection point) is not spelled out in UL498.
How do you reconcile your use of termination with UL's White Book?
PVVA "feed through termination"
Panelboard Marking Guide "feed-through terminal"

I also doubt if that connection is rated for feed-through loop.
This is your personal opinion, which you have yet to substantiate.
 

kwired

Electron manager
Location
NE Nebraska
Nice try. It can be debated as to where the GEC changes from a GEC to a bonding jumper past the 'screw' but the acorn is rated for that single conductor. The screw on the device is rated for one conductor 'terminating' on it. I also doubt if that connection is rated for feed-through loop.

Think about what happens under a heavy current draw if your 'looped wire' is to close to itself? Arcing come to mind?

In order for this arc to develop there would need to be a difference of potential. Since it is all one piece of conductor and less than 3/4 inch or so long do you really think you can draw enough current without melting it down to drop the voltage enough to arc across that particular point?

edit to add: now if you put two conductors under the screw and have some resistance between for any reason - you as well as most of us understand that though, and do know that is not an acceptable installation.
 
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jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
Single and duplex receptacles rated 15 and 20 A that are provided with more than one set of terminals for the connection of line and neutral conductors have not been investigated to feed branch-circuit conductors connected to other outlets on a multi-outlet branch circuit, as follows:
Side wire (binding screw) terminal with its associated back wire (screw actuated clamp type) terminal
Multiple conductors under a single binding screw
Multiple conductors in a single back wire hole

http://www.iaei.org/magazine/2008/1...zing-both-the-side-and-back-wiring-terminals/

Now does this mean it is OK if I stay in the same 'box'?

The more I read the more cornfused I get!
 

PetrosA

Senior Member
Yes. It is more than one conductor. It is one wire but two conductors. (...)

This raises another interesting question. If each loop counts as a separate conductor, then jumpers out of a wirenutted splice would also count as a conductor. In that case, would a three gang new-work Carlon box (44 cu. in. rated for 22 14AWG conductors) be undersized with three three wires for three-ways, one two-wire feed in and two two-wire feeds out if all three three-way switches were Lutron Maestro ELV dimmers that each required a neutral jumper as well as a hot? By my count you would have 23 14AWG conductors at that point (not to mention some pretty massive splices and wirenuts...). In my mind, looping the hot and neutral to these switches wouldn't increase the conductor count (remove all the switches and you still only have two conductors coming out of the box and in fact would offer much more airflow in the box that splicing jumpers together and packing them in. Especially in a situation with three dimmers, ELV or not, I worry much more about heat in the box and damage it might do the wires or switches than the very slight chance of a massive voltage spike causing some kind of arc (Probably more than 90% of the boxes will be a CAT II location with only those close to the service being in a CAT III location). Whereas if you splice jumpers together, you have every dimmer in the gang sinking heat into the jumpers' splice which could weaken the connection. The loops will dissipate the heat more safely as there aren't any wirenutted connections between the switches.
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
This raises another interesting question. If each loop counts as a separate conductor, then jumpers out of a wirenutted splice would also count as a conductor. In that case, would a three gang new-work Carlon box (44 cu. in. rated for 22 14AWG conductors) be undersized with three three wires for three-ways, one two-wire feed in and two two-wire feeds out if all three three-way switches were Lutron Maestro ELV dimmers that each required a neutral jumper as well as a hot? By my count you would have 23 14AWG conductors at that point (not to mention some pretty massive splices and wirenuts...). In my mind, looping the hot and neutral to these switches wouldn't increase the conductor count (remove all the switches and you still only have two conductors coming out of the box and in fact would offer much more airflow in the box that splicing jumpers together and packing them in. Especially in a situation with three dimmers, ELV or not, I worry much more about heat in the box and damage it might do the wires or switches than the very slight chance of a massive voltage spike causing some kind of arc (Probably more than 90% of the boxes will be a CAT II location with only those close to the service being in a CAT III location). Whereas if you splice jumpers together, you have every dimmer in the gang sinking heat into the jumpers' splice which could weaken the connection. The loops will dissipate the heat more safely as there aren't any wirenutted connections between the switches.

Good point.

(1) Conductor Fill. Each conductor that originates outside
the box and terminates or is spliced within the box shall be
counted once, and each conductor that passes through the
box without splice or termination shall be counted once.
Each loop or coil of unbroken conductor not less than twice
the minimum length required for free conductors in 300.14
shall be counted twice. The conductor fill shall be calculated
using Table 314.16(B). A conductor, no part of which
leaves the box, shall not be counted.


Now could this apply to loops? If they are long enough?

(1) Conductor Fill. Each conductor that originates outside
the box and terminates or is spliced within the box shall be
counted once, and each conductor that passes through the
box without splice or termination shall be counted once.
Each loop or coil of unbroken conductor not less than twice
the minimum length required for free conductors in 300.14
shall be counted twice. The conductor fill shall be calculated
using Table 314.16(B). A conductor, no part of which
leaves the box, shall not be counted.
 

hurk27

Senior Member
Yes. It is more than one conductor. It is one wire but two conductors.

One wire but two conductors???:?

If this is your definition of this then explain how you are allowed to use a split bolt to tap a mid stream splice where it is only allowed to connect two conductors together?

In all my many years of doing connections I have never ever had anyone try to ever say one wire is two conductors just because it is center tapped whether it is wrapped around a screw unbroken or by using a split bolt to center tap mid-span.

And as for arcing, the only possible way there would be an arc is if the screw on the receptacle was not correctly tightened down and only the load on the receptacle could cause it not a down stream load, with no break in the conductor there is no possible loss of connection unless you think the electrons quit flowing in the conductor because they can't make the curve:roll:

There is no scientific reason to explain you theory, much less the purported reference you chose to use, as anyone with any comprehension of the English language can clearly see the IAEI reference you posted is about multiple wires that are not continuous making multiple connection to the same screw, as it even points out two conductors into the same back stab hole which could not be possible with a continuous wire/conductor.

Oh by the way, the word "wire" is only a description of a type of conductor in the context of most all electrical definitions the two are one in the same, so if you wish to look up the definition of the word "wire" as in its electrical definition you will find it is a conductor, to say other wise is just plain foolish.

The unbroken loop connection is one of the most common connection types use across the nation when using conduit wiring methods, and has been used far before we were ever in this trade, I have seen its use even in K&T with dating going back into early 1920's, many electrical hand books have had images showing this type of connections both new and old as far back as I can remember.
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
"IMO this is just a matter of workmanship and training. The apprenticeship classes teach about torquing terminals. BTW, UL does torque all terminations for testing. I generally do not see a problem but I do know that most electricians use a standard screwdriver instead of a torquing screwdriver.

As far as I am concerned, the UL White Book is part of the Code. "

http://forums.mikeholt.com/showthread.php?t=68770

post #7

post #8 is pretty good too

"And in most if not all they do show the proper way to wrap the wire around the screw terminal and the required torque."
 

hurk27

Senior Member
Mike try reading the hand book, take a look at the commentary to 300.13(B)

well this:
Grounded conductors (neutrals) of multiwire branch circuits
supplying receptacles, lampholders, or other such devices
are not permitted to depend on terminal connections
for continuity between devices. For such installations (3- or
4-wire circuits), a splice is made and a jumper is connected
to the terminal, unless the neutral is looped; that is, a receptacle
or lampholder could be replaced without interrupting
the continuity of energized downstream line-to-neutral
loads (see the commentary following 300.14). Opening the
neutral could cause unbalanced voltages, and a considerably
higher voltage would be impressed on one part of a
multiwire branch circuit, especially if the downstream lineto-
neutral loads were appreciably unbalanced. Section
210.4(B) requires simultaneous disconnection of all ungrounded
conductors for each multiwire branch circuit. See
the associated commentary following 210.4(B). The requirement
of 300.13(B) does not apply to individual 2-wire
circuits or other circuits that do not contain a grounded
(neutral) conductor.

Wow it even says "LOOPED" now remember who writes these commentary's
It defiantly recognizes that we "loop" conductors around the screws.
 

jxofaltrds

Inspector Mike®
Location
Mike P. Columbus Ohio
Occupation
ESI, PI, RBO
Mike try reading the hand book, take a look at the commentary to 300.13(B)

well this:


Wow it even says "LOOPED" now remember who writes these commentary's
It defiantly recognizes that we "loop" conductors around the screws.

Yes wow. I'll look for it. TY.

EDIT: While not enforcable I listen to the commentary.
 
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kwired

Electron manager
Location
NE Nebraska
"IMO this is just a matter of workmanship and training. The apprenticeship classes teach about torquing terminals. BTW, UL does torque all terminations for testing. I generally do not see a problem but I do know that most electricians use a standard screwdriver instead of a torquing screwdriver.

As far as I am concerned, the UL White Book is part of the Code. "

http://forums.mikeholt.com/showthread.php?t=68770

post #7

post #8 is pretty good too

"And in most if not all they do show the proper way to wrap the wire around the screw terminal and the required torque."

NEC does not require things to be listed by UL. Any NRTL is acceptable in most cases. Outside of informational notes (FPN's in older editions) UL itself may not even be mentioned. White book only tells you what criteria UL uses for their listing standards.

I don't see what (in general) is so unworkmanlike about this practice. I have more confidence in the conductive integrity of a conductor looped from switch to switch in a multigang box than I have in a big wire nut and assurance all the conductors are engaged well enough into that wire nut to never come loose. If it is an equipment grounding conductor you may never know anything came loose as normal operation of the circuit will not be effected
 

Stevareno

Senior Member
Location
Dallas, TX
I have more confidence in the conductive integrity of a conductor looped from switch to switch in a multigang box than I have in a big wire nut and assurance all the conductors are engaged well enough into that wire nut to never come loose. If it is an equipment grounding conductor you may never know anything came loose as normal operation of the circuit will not be effected

This. I can't count the number of times I've had to troubleshoot a connection problem. Most common culprit? A loose wirenut.
I've come across many installations that A) wires weren't twisted together, and B) wirenut was not tight.
 
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