Thread: Parallel conductors in the home

This is really two questions. Are parallel conductors something we might find in the home, and if so where, A/C unit? And I believe the two wires of parallel conductors are joined together at each end. so would you recognize that as two wires obviously joined together? In the service panel, bus bars that allow two conductors in same hole are identified as such. Is this an obvious ID? Is it right at the hole and obvious? OK 4 questions sorry and thanks you very much!! Brian

Similar Threads:

• Home, sweet home if you had a good inspector - TheNewsTribune.com
• White Conductors, Red Tape
• YOUR PLACE TO CALL HOME: Is a home inspection worth the money? - Suburban Journals
• White Conductors used as "Hot"
• Grounded (neutral) conductors

Originally Posted by Brian Robertson

This is really two questions. Are parallel conductors something we might find in the home, and if so where, A/C unit? Yes --they are allowed as long as they are 1/0 or larger. Don't confuse this NEC wiring method with what you may observe inside an appliance.


And I believe the two wires of parallel conductors are joined together at each end. so would you recognize that as two wires obviously joined together? Yes they have to terminate the same, be exactly the same length, the same insulation, same size and same conductor material

In the service panel, bus bars that allow two conductors in same hole are identified as such. Is this an obvious ID? Sometimes. The opening will be a sort of figure 8 shape rather then round. The size and number of conductors will be on the label or stamped on the terminal lug. Not always easy to find.

Is it right at the hole and obvious? Same as the above

OK 4 questions sorry and thanks you very much!! Brian

Probably only three questions

Since there would be no need for a conductor larger than 1/0 in a residential setting, other than for a service entrance conductor, the short answer is NO, you will not find them in a resi setting.

The NEC does't limit the use. I have inspected homes with 1600 amp services and up to 8 subfed panels. Nothing prohibits the use of parallel conductors.

Jim you just said "yes" and then said "no" --you can't have it both ways

The way I meant my answer was that you will not see a paralleled conductor except when used in a service.

There would be no other equipment that would require a conductor that large, ie the AC that was mentioned in the OP would not require parallleled conductors. If it were to be fed by parallels it would be an improper use of paralleling.

Originally Posted by Jim Port

The way I meant my answer was that you will not see a paralleled conductor except when used in a service.

There would be no other equipment that would require a conductor that large, ie the AC that was mentioned in the OP would not require parallleled conductors. If it were to be fed by parallels it would be an improper use of paralleling.

Feeders? Parallel EGCs smaller than 1/0?

Like Jim said - You can only parallel conductor sizes 1/0 and up.

Originally Posted by ken horak

Like Jim said - You can only parallel conductor sizes 1/0 and up.

Like Roland said, that does not mean you will not find them in a residence.

Originally Posted by Jim Port

The way I meant my answer was that you will not see a paralleled conductor except when used in a service.

Nobody is saying you Won't find them in a house. Just clarifying the requirement of 1/0 and larger.

You can use 1/0 for what ever you choose as long as it doesn't exceed the ampacity rating of the wire. Hell some folks wire 15 amp circuits with 12 wire. Some would like to see all 10 wire!
Why who knows

Originally Posted by ken horak

Nobody is saying you Won't find them in a house. Just clarifying the requirement of 1/0 and larger.

The minimum 1/0 AWG rule for parallel conductors of 310.4 doesn't apply to equipment grounding conductors (EGCs) run in parallel [250.122(F)(1)].

Originally Posted by ken horak

Hell some folks wire 15 amp circuits with 12 wire. Some would like to see all 10 wire!
Why who knows

Why? Voltage drop.

That's why.

First and foremost, #12 AWG does not fit into the back-stab holes in the devices, which means the #12 must be installed under the screw terminal, which right there solves many voltage drop issues. Then, the additional size and resulting in reduction of resistance, the voltage drop over long circuit runs is greatly reduced.

No need to heat the wire just trying to get voltage at the other end.

Originally Posted by ken horak

Hell some folks wire 15 amp circuits with 12 wire. Some would like to see all 10 wire!
Why who knows

Possibly compensating for voltage drop on longer circuits.

Echo. Must be the turtle speed connection .

Originally Posted by H.G. Watson, Sr.

The minimum 1/0 AWG rule for parallel conductors of 310.4 doesn't apply to equipment grounding conductors (EGCs) run in parallel [250.122(F)(1)].

Oh- but it does.
That section starts off with: WHERE conductors are run in parallel in multiple raceways or cables as permitted in 310.4 the equipment grounding conductors, where used, shall be run in parallel in EACH raceway or Cable.

This is telling you how to size the Equipment Grounding Conductor WHEN you have parallel conductors. So.... If you can only parallel 1/0 and larger then the only time you are paralleling the EGC is when you have a parallel run - which we all know must be 1/0 or larger.
This means that the 1/0 rule does apply to EGC's-
No Parallel run of 1/0 or larger - NO parallel EGC's

Originally Posted by H.G. Watson, Sr.

The minimum 1/0 AWG rule for parallel conductors of 310.4 doesn't apply to equipment grounding conductors (EGCs) run in parallel [250.122(F)(1)].

Originally Posted by ken horak

Oh- but it does.
That section starts off with: WHERE conductors are run in parallel in multiple raceways or cables as permitted in 310.4 the equipment grounding conductors, where used, shall be run in parallel in EACH raceway or Cable.

What I think Watson (no first name) was saying is that the requirement that the "equipment grounding conductors" are not required to be 1/0 or larger to be run in parallel.

When conductors are run in parallel, the equipment grounding conductors are also required to be run in parallel with the conductors run in parallel, however, the equipment grounding conductors are permitted to be smaller than 1/0 as they are allowed to be sized in accordance with the overcurrent device rating or in accordance with Table 250.122, which is the table used to size equipment grounding conductors.

Originally Posted by H.G. Watson, Sr.

The minimum 1/0 AWG rule for parallel conductors of 310.4 doesn't apply to equipment grounding conductors (EGCs) run in parallel [250.122(F)(1)].

Originally Posted by ken horak

Oh- but it does.
That section starts off with: WHERE conductors are run in parallel in multiple raceways or cables as permitted in 310.4 the equipment grounding conductors, where used, shall be run in parallel in EACH raceway or Cable.

This is telling you how to size the Equipment Grounding Conductor WHEN you have parallel conductors. So.... If you can only parallel 1/0 and larger then the only time you are paralleling the EGC is when you have a parallel run - which we all know must be 1/0 or larger.
This means that the 1/0 rule does apply to EGC's-
No Parallel run of 1/0 or larger - NO parallel EGC's

Ken Horak,

I was pointing out that the Equipment Grounding CONDUCTORS (EGCs)are CONDUCTORS, and when run in a parallel circuit are NOT subject to a minimum sizing of 1/0 as are the Ungrounded and Grounded CONDUCTORS of a parallel circuit. I was addressing a series of erroneously general statements made in the post series.

HG Watson-
I agree with you and understand what you are stating. The EGC Need not be 1/0. I also do hope you can see what I was saying also. That it all relys on the 1/0 rule when it comes to paralleling conductors.
I also am in agreement as toyour other post in this thread

Originally Posted by ken horak

HG Watson-
I agree with you and understand what you are stating. The EGC Need not be 1/0. I also do hope you can see what I was saying also. That it all relys on the 1/0 rule when it comes to paralleling conductors.
I also am in agreement as toyour other post in this thread

Thank you Ken Horak, and yes I do understand your point.

Originally Posted by Brian Robertson

This is really two questions. Are parallel conductors something we might find in the home, and if so where, A/C unit? And I believe the two wires of parallel conductors are joined together at each end. so would you recognize that as two wires obviously joined together? In the service panel, bus bars that allow two conductors in same hole are identified as such. Is this an obvious ID? Is it right at the hole and obvious? OK 4 questions sorry and thanks you very much!! Brian

Brian Robertson,

From your stated location "southern ontario" and from your prior posts I presume you are in the province of Ontario in Canada.

Discussions referring to the NEC or National Electrical Code on this site and area are usually referring to NFPA 70. This is an entirely DIFFERENT code than what is referred to as the "National Code" is really the "Canadian Electrical Code" which was passed in Ottawa (merely advisory) and which has been adopted in some form by most if not all of the Provincial amd Territorial Governments, which when so adopted as the Province or Territory has authored it becomes compulsory and has the power and is enforced under law.

Electrical Code rules in Ontario are not the same as they are in the United States on many issues, for example for the most part in the U.S. those areas which have adopted NFPA 70, "National Electrical Code" one of many editions, rarely has it been adopted without any ammendments. In its pure form, depending on the edition, "our" NEC does not restrict the maximum total number of receptacle outlets on general branch circuits for residential occupancies, as they do for non-residential occupancies; unlike Ontario, Canada's "rules".

I suspect your questions about various codes, what the authority might be, etc. might be better served if you address them to those who are familiar with the distinctly different form of government you have there in Canada. IIRC you have a Confederate form of National Government. You might check with your Provincial Government and your local Building Authority to derive what "codes" or regulations are in effect for your area.

Any discussion or reference on this thread and many others which refer to the "NEC" or the "National Electrical Code" unless qualified to be something other than a U.S. authored code, are referring to NFPA 70, which is authored in the United States. I do not believe that it is practiced in Canada. Canada's National "Canadian Electrical Code" is distinctly different and not the same thing. Ontario's Electrical Safety Code is distinctly different than the NEC we often reference on this site.

Back to the subject of your post:

Another thing that an inspector may come across is the multiwire branch circuit. Mistakes in this situation can create interesting consequences.

You may find this article "of interest" (especially considering a combination of "the old ways" I understand Kitchens in Ontario may have been wired, for example).

Multiwire Branch Circuits Can Be Dangerous

It makes for a good read and reminder for any HI, as in the U.S. especially in older installations it was common to have multi-wire branch circuits, and to wire "through" receptacles, as they were rated for same. With generations of wiring ammendments, repairs, and replacements and evolutions of code editions, and what code rules may have been in effect, it is something to be accutely aware of. Something as innocent as using a plug-in light indicating "circuit tester" can be dangerous in certain situations, including using on such a circuit.

Suggesting that the self-appointed electrical expert has not the qualifications he claims, and alleging a series of disciplinary actions, are serious attacks on the credibility of that person.

For the response to be an attack on the person of the critic is nothing but an attempt at distraction. The critic can be very flawed - but that is irrelevant if the 'expert' has not the claimed credentials.

More to the point .... what has any of this to do with the topic of the thread? IIRC, the OP wanted to know about parallel feeds.

Now, maybe I'm a bit provincial here, but it seems to me that any situation where you find parallel feeds is going to require expertise beyond the scope of a home inspection. Beyond noting their existance, and termination methods, I think the HI is out of his scope.

I'd ask the OP: Why do you ask? Is there a double-lugging issue? What's the application? Etc.

Offhand, I can't imagine any circumstance where you would find a parallel feed on a house.

Hi fellas, whoa!!!! I apologize to the rest of the members here for starting what seems to be one of the more particularly nasty, scraps between Jerry and (this time it's H.G. Watson). I have been following the thread and trying to trying to learn but the fighting certainly is a little unsettling. The reason for my question was just an FYI thing for myself. I wasn't very familiar with these parallel conductors and wanted to know if they are something I should expect to run in to and if so I wanted to be sure of what I was looking at. I have learned from the answers and thank those of you who contributed, I'll say it again as before, I love this site. Mr. Watson I'm not sure how much my country contributes to the writing of the NFPA, we certainly adhere to it, particularly for fire prevention enforcement. We follow the IRC, but as far as IIRC and the rest of your last comment directed at me, sorry but I don't even know what the heck your talking about! I am kind of new here and appreciate its not my place to be critical, but if your going to sucked in to a nasty pissing match with Jerry, why don't you try and get it moved over to a personal messaging area. Thanks Brian

Ok thanks H.G. you are probably more tuned into some of the stuff that relates to rules and regs. up here than I so its time for more research! Thanks all for the input! Brian

Originally Posted by Brian Robertson

Ok thanks H.G. you are probably more tuned into some of the stuff that relates to rules and regs. up here than I so its time for more research! Thanks all for the input! Brian

Ontario has its own electrical safety code and ontario building code.
You can research both on your province's official web site.

Your CSA approval standards for electrical equipment are different than our listing requirements.

Your color coding for electrical, plumbing, and other areas of building code and systems are very different. Your rules/codes are very different than ours.

NFPA doesn't author the IRC. IIRC means "if I recall correctly".

Get back to the topic.

Any personal differences need to be handled outside of InspectionNews.

Thank you.

Thanks Brian!

Damn I got here to late. I want the unrated topic back............

Yeah...what ever happened to the knock-down drag-out way of topic discussion? I think I was learning more that way!....

Some one asked why I asked about parallel feeds, and its probably out of my scope. Yeah it probably is, but the reason I asked about it is because I was on another site of Jerry's I think codeman , and found a discussion about parallel conductors. It was just a question to find out if a parallel conductor was something I might run into in a residential setting. Thats all.