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54067323

join:2012-09-25
Tuscaloosa, AL

How to calculate the amperage of paralleled conductors???

In this case it would be 4 number 10 stranded conductors paralleled.

So what awg would that equal???


Speedy Petey

join:2008-01-19
This is a hypothetical question, right?
Are you aware that by code you CANNOT parallel conductors that small?

I realize this does not answer your question, but since it is not allowable by code IMO it is not worth even doing the math.

What are you doing that would require this?

garys_2k
Premium
join:2004-05-07
Farmington, MI
Reviews:
·Callcentric
reply to 54067323
A number 10 wire is 6 mm2, so four of them would be 24 mm2, a bit less than a number 4 wire. »www.landersinc.com/With_fl/Html/···ABLE.pdf

TheMG
Premium
join:2007-09-04
Canada
kudos:3
Reviews:
·NorthWest Tel
reply to 54067323
In theory, it would be the sum of the ampacity of all 4 conductors. If the 4 conductors are in close proximity, then the ampacity would also have to be de-rated to take into account the effects of reduced heat dissipation.

As far as the electrical code is concerned, whether it is allowable or not, I can't answer that.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to Speedy Petey
said by Speedy Petey:

This is a hypothetical question, right?

No this is reality.

Are you aware that by code you CANNOT parallel conductors that small?

I can most certanily can and it's not about code, it's a temp setup and I only have access to the in-place conductors and no possibility of re-pulling new ones.

Now if you can advise how many amps I can push down 4 number tens please let me know, if not then pass over this thread.



54067323

join:2012-09-25
Tuscaloosa, AL
reply to garys_2k
said by garys_2k:

A number 10 wire is 6 mm2, so four of them would be 24 mm2, a bit less than a number 4 wire.

Thank you, I calculated the load at 56 amps and that information keeps me well within the margin I have to work with...


guppy_fish
Premium
join:2003-12-09
Lakeland, FL
kudos:3
reply to 54067323
Its not allowed,even temporarily ( code wise ), the reason is if one of the conductors fails, the it overloads the remaining wires.

As for current carrying ability, its not just the gauge of the wire, but the distance.


John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8
reply to 54067323
Parallel conductors smaller than 1/0 ARE allowed under the NEC.

Refer to NEC 310.4...

They are also allowed in machines installed in buildings and structures covered under the NEC...


cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7
reply to guppy_fish
said by guppy_fish:

Its not allowed,even temporarily ( code wise ), the reason is if one of the conductors fails, the it overloads the remaining wires.

BUT IT'S A TEMPORARY SETUP SO CODE DOESN'T MATTER DAMNIT.

As for current carrying ability, its not just the gauge of the wire, but the distance.

Not to mention derating due to more than 3 conductors and temperature correction.

I also wonder if that is 4 total conductors that need split between the line and neutral, or 4 pairs of line AND neutrals.


nunya
LXI 483
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:12
Reviews:
·Charter
·voip.ms

1 recommendation

reply to 54067323
No.
It's not allowed temporary or not. Just because you don't get the answer you want, you don't have the right to tell people to piss off.
You are a short timer to this site and came here asking for a "how-to" to do something potentially dangerous.
--
If someone refers to herself / himself as a "guru", they probably aren't.


cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7
reply to John Galt
said by John Galt:

Parallel conductors smaller than 1/0 ARE allowed under the NEC.

Refer to NEC 310.4...

They are also allowed in machines installed in buildings and structures covered under the NEC...

They are NOT allowed except in a few limited exceptions, neither of which apply here. Exception 1 wouldn't as the ampacity of any single conductor isn't enough to carry the total current. Exception 2 doesn't apply because it's not engineering supervised. If it was, the question wouldn't be asked here.

said by NEC 2008 :
310.4 Conductors in Parallel.
(A) General. Aluminum, copper-clad aluminum, or copper
conductors of size 1/0 AWG and larger, comprising each
phase, polarity, neutral, or grounded circuit conductor shall
be permitted to be connected in parallel (electrically joined
at both ends).
Exception No. 1: Conductors in sizes smaller than 1/0
AWG shall be permitted to be run in parallel to supply
control power to indicating instruments, contactors, relays,
solenoids, and similar control devices, or for frequencies of
360 Hz and higher, provided all of the following apply:
(a) They are contained within the same raceway or
cable.
(b) The ampacity of each individual conductor is sufficient
to carry the entire load current shared by the parallel
conductors.
(c) The overcurrent protection is such that the ampacity
of each individual conductor will not be exceeded if one
or more of the parallel conductors become inadvertently
disconnected.
Exception No. 2: Under engineering supervision,
grounded neutral conductors in sizes 2 AWG and larger
shall be permitted to be run in parallel for existing
installations.
FPN to Exception No. 2: Exception No. 2 can be used to
alleviate overheating of neutral conductors in existing installations
due to high content of triplen harmonic currents.

(B) Conductor Characteristics. The paralleled conductors
in each phase, polarity, neutral, grounded circuit conductor,
or equipment grounding conductor shall comply
with all of the following:
(1) Be the same length
(2) Have 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

(C) Separate Cables or Raceways. Where run in separate
cables or raceways, the cables or raceways with conductors
shall have the same number of conductors and shall have
the same electrical characteristics. Conductors of one
phase, polarity, neutral, grounded circuit conductor, or
equipment grounding conductor shall not be required to
have the same physical characteristics as those of another
phase, polarity, neutral, grounded circuit conductor, or
equipment grounding conductor to achieve balance.

(D) Ampacity Adjustment. Conductors installed in parallel
shall comply with the provisions of 310.15(B)(2)(a).

(E) Equipment Grounding Conductors. Where parallel
equipment grounding conductors are used, they shall be
sized in accordance with 250.122. Sectioned equipment
grounding conductors smaller than 1/0 AWG shall be permitted
in multiconductor cables in accordance with 310.13,
provided the combined circular mil area in each cable complies
with 250.122.
310.4 also was moved for NEC 2011 to 310.10(H) FYI.


John Galt
Forward, March
Premium
join:2004-09-30
Happy Camp
kudos:8
said by cdru:

They are NOT allowed except in a few limited exceptions, neither of which apply here.

The larger point is that blanket statements as to what is or is not allowed by the NEC do a disservice to posters in the forum without an understanding of the particular nuances of the Code, or the intended application.

My response addressed that issue, not the OPs query.
--
Don't ask questions -- just do as you're told.



JustBurnt

@rr.com
reply to 54067323
What is your definition of "temp setup" in this case?


alkizmo

join:2007-06-25
Pierrefonds, QC
kudos:1
said by JustBurnt :

What is your definition of "temp setup" in this case?

Temporary setup... yeah right, what needs that much power temporarily?

Considering he needs around 50A, I'm guessing a heat pump or range.

Speedy Petey

join:2008-01-19
reply to John Galt
said by John Galt:

The larger point is that blanket statements as to what is or is not allowed by the NEC do a disservice to posters in the forum without an understanding of the particular nuances of the Code, or the intended application.

My response addressed that issue, not the OPs query.

So by us saying it is not allowed in this case, you think that is doing a "disservice"?? Seriously?? Do you think the OP, or ANYONE else on this forum, might have an application that would be allowed under the exception??

IMO sometimes it is NOT worth the bother to say "It is not allowed, except only under some very rare and odd situations such as ........."

Bob4
Account deleted

join:2012-07-22
New Jersey
Reviews:
·Optimum Online
reply to 54067323
said by 54067323:

I can most certanily can and it's not about code, it's a temp setup and I only have access to the in-place conductors and no possibility of re-pulling new ones.

Then the correct answer (to the people who want you to do this) is: No, it cannot be done legally.


cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7
reply to John Galt
said by John Galt:

The larger point is that blanket statements as to what is or is not allowed by the NEC do a disservice to posters in the forum without an understanding of the particular nuances of the Code, or the intended application.

My response addressed that issue, not the OPs query.

How is your response any better? IMHO from a safety standpoint, just saying no they are not allowed and not mentioning that there may actually be exceptions (which don't even apply here) is better than saying yes they are allowed and not mentioning that it's only allowed in a very limited circumstances.


Jack Legg

@comcast.net
reply to 54067323
@anyone

Hypothetically, what if each of the individual #10 conductors (including any paralled neutrals) was protected by a 30 amp breaker?

(I realize it wouldn't meet code requirements.)


cdru
Go Colts
Premium,MVM
join:2003-05-14
Fort Wayne, IN
kudos:7
said by Jack Legg :

Hypothetically, what if each of the individual #10 conductors (including any paralled neutrals) was protected by a 30 amp breaker?

If they meet all the conditions posted above under 310.4(B), they were all connected to the same leg at the panel, and not applying any deratings for various reasons, then you theoretically could have up to 30 amps per conductor. If the wires were different lengths or types, then the resistance differs between them which alters how the current is divided between them, making them unbalanced.

The problem isn't only what you can get out of the wires. It's protecting equipment, property, and people if/when something bad happens.

garys_2k
Premium
join:2004-05-07
Farmington, MI
Reviews:
·Callcentric
reply to 54067323
said by 54067323:

said by garys_2k:

A number 10 wire is 6 mm2, so four of them would be 24 mm2, a bit less than a number 4 wire.

Thank you, I calculated the load at 56 amps and that information keeps me well within the margin I have to work with...

Do you have two circuits that you need to parallel to run a single 56 A load (where the total of four conductors includes two "hots" and two neutrals, EACH being paralleled to two pairs of conductors will carry the total current)? Or, you have four circuits (four hots, four neutrals) that you will parallel to run this load?


PeeWee
Premium
join:2001-10-21
Madera, CA
reply to 54067323
If you are doing this at a place of work you are nullifying any insurance coverage and assuming 100% liability if anything happens. How deep are your pockets? If you are doing this in your own home you are unnecessarily endangering your family, and the same thing with insurance.
--
Iphone. Helping computer illiteracy become popular since 2007

Bob4
Account deleted

join:2012-07-22
New Jersey
Reviews:
·Optimum Online

1 recommendation

reply to alkizmo
said by alkizmo:

Considering he needs around 50A, I'm guessing a heat pump or range.

Maybe a grow house?


pende_tim
Premium
join:2004-01-04
Andover, NJ
kudos:1
Reviews:
·Comcast
reply to 54067323
30 Amps max, if copper. depending on the insulation type and wire count in the conduit it may have to be derated.
--
The difference between genius and stupidity is that genius has its limits.

itguy05

join:2005-06-17
Carlisle, PA

1 recommendation

reply to PeeWee
said by PeeWee:

If you are doing this at a place of work you are nullifying any insurance coverage and assuming 100% liability if anything happens. How deep are your pockets? If you are doing this in your own home you are unnecessarily endangering your family, and the same thing with insurance.

Insurance covers stupidity. Just like "not using UL will void your homeowners" is not true. They may very well pay out one time and one time only but insurance will cover being stupid.

That being said it's unsafe and should not be done.


PSWired

join:2006-03-26
Annapolis, MD

2 recommendations

It's like someone's planning a nuclear apocalypse here every time a minor code violation is suggested. Good grief.

In the future we should be better at mentioning *why* the code prohibits things like this. People are much more likely to find a way to get their problem solved in a compliant manner if they understand the risks, rather than being told that the world will end for some unspecified reason if they don't do as they're told.


SparkChaser
Premium
join:2000-06-06
Downingtown, PA
kudos:4
Reviews:
·Verizon FiOS
PSWired See Profile], I understand what you are saying but 'it comes down to can you do that YES, should you NO.'

The problem with forums like this is (when it comes to electricity or gas or other dangerous "home" projects) , if you have to ask the question, you probably shouldn't be doing it.

No one want to be responsible for someone doing something stupid.
.
--
--
--
"Facts do not cease to exist because they are ignored." - Aldous Huxley


mattmag
Premium,ExMod 2000-03
join:2000-04-09
NW Illinois
kudos:3
said by SparkChaser:

The problem with forums like this is (when it comes to electricity or gas or other dangerous "home" projects) , if you have to ask the question, you probably shouldn't be doing it.

I most always respect your contributions, but that is just so not true. How else should a person teach? Is there not always a risk involved with *any* educational effort within a technological field?

I spent many years teaching EMT's to become a Paramedic. If they screw up, people can die. Should we not allow them to learn by doing? Of course not. One can't effectively learn how to start an IV simply by being told. We guide, we teach, we answer questions, and it all ends up furthering the education and skills of the student. There is always the risk, but the proper education is worth the chance.

I will always remember my dear mother telling me the story of how one night I stood in the kitchen as a wee young lad, and kept asking if the stove was hot. She kept telling me "Yes, it is hot". I kept asking. Finally, I touched the stove, and of course immediately jerked my finger back in pain. Sometimes learning by doing is the best teacher of all.

Bob4
Account deleted

join:2012-07-22
New Jersey
If someone comes on here asking if they can use a lighted match to search for a gas leak, you'd let them "learn by doing"?


guhuna
5149.5
Premium
join:2001-03-31
Port Costa, CA
Reviews:
·PHONE POWER
reply to Bob4
said by Bob4:

said by alkizmo:

Considering he needs around 50A, I'm guessing a heat pump or range.

Maybe a grow house?

50amps for a grow op? Damn son that's small......

scooper

join:2000-07-11
Youngsville, NC
kudos:2
reply to 54067323
You know - I asked this same question six or more months ago (maybe more like 18), with basically the same answers. Maybe a good reason to have people read old posts before posting questions ?....