wire guage simple question

[chopped]

I was wondering if this would hold true.
If I wanted to have a 10 gauge wire but run two 14 gauge ones on the same terminal. would this amount to a 7 gauge?Ive seen people double up conductors before to gain the lower gauge.
Thanks

 

[CurlyDave]

Usually this is not allowed by the electrical code.

 

[rus_geek]

14 AWG carries approximately half the current of 9 or 11 AWG, depending on the reference table, so it'd be pretty close to your 10 AWG requirement. I'm not 100% positive if you can do simple "addition" of capacities when it comes to running multiple separate conductors, but it logically makes sense to me. You should individually fuse each conductor, too.

To throw a different set of numbers at it:
The resistance of 10AWG wire is 1.018 ohms per 1000 feet.
Two 14AWG have a resistance of 1.2878 ohms per 1000 feet. Greater voltage drop.
A 14AWG and 12AWG in parallel have .995 ohms per 1000 feet.

-r-

 

[ren1pa]

Wire gauge is a measure of diameter. In order to increase the gauge from 14 to 7 you would require increasing the diameter from 0.0641", to 0.1443".

14 gauge = 0.0641" diameter.
7 gauge = 0.1443" diameter.

Another example:
If you wrap 6, of your 14 gauge wires around a center 14 gauge wire, you would triple the diameter to 0.01923", resulting in a "4.5 gauge" wire.

4 gauge = 0.2043" diameter.
5 gauge = 0.1819" diameter.

See also:
American wire gauge - Wikipedia, the free encyclopedia

Hope this helps.

rr

 

[rus_geek]

...I'll mention a practical thought...

Haven't you been around long enough to know those aren't allowed?

You have a point, though. We addressed the "can you" moreso than the "should you" aspect. But it gives me an excuse to use obscure math . . .


-r-

 

[hr3]

The question for "chopped" should be "Are you taking ac or dc voltage"..It does matter..

 

[ModMech]

Actually.....

Wire gauge is not a measure of diameter, but one of (cross sectional) AREA. In fact, most other countries use "square millimeters" and not "gauge" to specify wire.

When referring to sheet stock, "gauge" does in fact, refer to thickness of the material but not for wire - specifically.

The table I use for ampacity is here: American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies

If you double the area, you effectively double the current carrying.

If you double the diameter, you increase the current carrying by as much as 4 times, because the area is 4 times greater.

Examples:

16 AWG = 0.0508" diameter, R(adius) = 0.0254, A(rea) = 2*pi*R^2 = 0.004054"
16 AWG carries 3.7 Amps (power)

10 AWG = 0.1016 (apx 2 x 16 AWG), R = 0.05080, A = 0.016215 (apx 4 times more area and 1/4 of the ohms/1000ft))
10 AWG carries 15 Amps (power), more than four times the 16 AWG because of the reduced resistance.

 

[Hozen]

10ga carries a lot more than 15 amps... and 16ga will carry more than 3.7.

AC vs DC does matter to some degree (but, not really).

Most electricians you talk to will tell you 14ga will carry 15A, 12ga carries 20A, 10ga 30A. This is all in the context of romex carrying AC and fairly short runs (aka, not 300 feet).

A 7ga wire (not standard btw) is between 6 and 8 and if we assume it's stranded and not solid and copper and not aluminum, you're looking at around 50A capacity roughly.

It also depends on whether the wire insulation is rated for 60C or 90C. The higher the rating, the more amps it can safely carry.

Others have already touched on it, but using two small wires is pretty much a hack. Plus, in this case, 10ga wire can be picked up at any local home depot or lowes and is fairly cheap.

I think you'd get better/more accurate responses if you describe what you're planning to do.

 

[Soundguy]

If I needed a 10ga wire to run from my tractor alt to my bat terminal.. or wherever.. from a lamp switch to a lamp, I'd use one fuse for the PAIR of wires, treating them as 1 wire, I'd also solder them vs crimp connectors.

BTDT have plenty of old tractors with wire harnes made from 14awg brake wire loom lines,with a double line from the generator instead of a 10awg which is what i would prefer..

I would not do this on a roadmobile..

soundguy

14 AWG carries approximately half the current of 9 or 11 AWG, depending on the reference table, so it'd be pretty close to your 10 AWG requirement. I'm not 100% positive if you can do simple "addition" of capacities when it comes to running multiple separate conductors, but it logically makes sense to me. You should individually fuse each conductor, too.

To throw a different set of numbers at it:
The resistance of 10AWG wire is 1.018 ohms per 1000 feet.
Two 14AWG have a resistance of 1.2878 ohms per 1000 feet. Greater voltage drop.
A 14AWG and 12AWG in parallel have .995 ohms per 1000 feet.

-r-

 

[rus_geek]

Only reason I recommend separate fusing, is what if one of the two conductors takes some damage? You can dump *all* of the current to a single conductor but still be within the operating range of the fuse.

-rus-

If I needed a 10ga wire to run from my tractor alt to my bat terminal.. or wherever.. from a lamp switch to a lamp, I'd use one fuse for the PAIR of wires, treating them as 1 wire, I'd also solder them vs crimp connectors.

BTDT have plenty of old tractors with wire harnes made from 14awg brake wire loom lines,with a double line from the generator instead of a 10awg which is what i would prefer..

I would not do this on a roadmobile..

soundguy

 

[EE_Bota]

Now sure if it helps, but I have 2 x(750MCM 3 phase) for a total of 6 750MCM
conductors running a production process. These are parallel. So, apparently you can do what it makes sense. I didn't know what to do otherwise, and neither did the PE I hired to help sort the zig-zag transformer grounding.

These conductors are made to be the exact same length.

I will tell you what does NOT work in parallel: DC motor interpoles. Most interpoles I have ever seen are series connected, but some of the low diameter European motors have the interpoles connected in parallel! What a hateful thing to do.

 

[hr3]

Why would one assume he is talking about 12 volts dc ??? Voltage drop in % is the same but if you lose 2 volts from a 120v supply not much of a problem.. When you lose 2 volts from a 12v circuit,,Well that's a different story,,,

Like he said he had a simple question.. kis

 

[rd_macgregor]

ModMech,
One small glitch in your calculations. Circumference is 2piR, while area is pi R squared; you mixed the two and showed a formula for calculating twice the area.
BOB

 

[killdozerd11]

As i have worked as a maintenance mechanic in a bolt factory

The general rule is... Bubble gum-Baling wire and tape and whatever you have on hand to get it safely back on line

And do the correct repair after the work day is done

If you ever do this for a living you got to love over time and working under pressure and you have to think on your feet

I would not do what you asking about as a permanent fix

 

[bdeboer]

Now sure if it helps, but I have 2 x(750MCM 3 phase) for a total of 6 750MCM
conductors running a production process. These are parallel. So, apparently you can do what it makes sense. I didn't know what to do otherwise, and neither did the PE I hired to help sort the zig-zag transformer grounding.

This is allowed by the NEC for larger conductor sizes/amperages. Due to the fact the wire & conduit sizing would not be practical.

 

[ModMech]

10ga carries a lot more than 15 amps... and 16ga will carry more than 3.7.

If you look at the chart it specifically gives the rating I offered for automotive load carrying.

AC vs DC does matter to some degree (but, not really).

No, it matters, really. Most automotive wire, assumed in this conversation, has a completely different inductance and frequency response from stranded wire of the same area. For normal power and ground circuits however, you are correct it really doesn't matter if referring to AC or DC loads.

Most electricians you talk to will tell you 14ga will carry 15A, 12ga carries 20A, 10ga 30A. This is all in the context of romex carrying AC and fairly short runs (aka, not 300 feet).

My father-in-law is a Master Electrician with 30+ years as a Journeyman and he will tell you that the load carried is dependant on the circuit voltage, power factor and length of the run.

 

[DonnieP]

From Canadian Electrical Code:
12-108 Conductors in parallel (see Appendix B)
(1) Conductors of similar conductivity in sizes No. 1/0 AWG copper or aluminum and larger shall be permitted
in parallel provided that they are
(a) free of splices throughout the total length;
(b) the same circular mil area;
(c) the same type of insulation;
(d) the same length; and
(e) terminated in the same manner.
(2) The orientation of single-conductor cables in parallel, with respect to each other and to those in other
phases, shall be such as to minimize the difference in inductive reactance and the unequal division of
current.
(3) Conductors of similar conductivity in sizes smaller than No. 1/0 AWG copper shall be permitted in parallel
to supply control power to indicating instruments and devices, contactors, relays, solenoids, and similar
control devices provided that
(a) they are contained within one cable;
(b) the ampacity of each individual conductor is sufficient to carry the entire load current shared by the
parallel conductors; and
(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 becomes inadvertently disconnected.
(4) Where the size of neutral conductors is reduced in conformance with Rule 4-022, neutral conductors
smaller than No. 1/0 AWG shall be permitted in circuits run in parallel, provided that they are installed in
conformance with the requirements of Subrule (1)(a), (b), (c), (d), and (e).

 

[dcyrilc]

I was wondering if this would hold true.
If I wanted to have a 10 gauge wire but run two 14 gauge ones on the same terminal. would this amount to a 7 gauge?Ive seen people double up conductors before to gain the lower gauge.
Thanks

The short answer is NO. The math doesn't work that way. Two number 14's would be closer to a number 10.

In certain cases, wire can be doubled and run parallel for higher amperages, but it doesn't work the way you were asking.

 

[Soundguy]

Only reason I recommend separate fusing, is what if one of the two conductors takes some damage? You can dump *all* of the current to a single conductor but still be within the operating range of the fuse.

-rus-

if the wire takes damage like chafing... hopefully the fuse will pop!

soundguy

 

[patrick_g]

Is there a magic conveyor belt involved in this somewhere?