# Electrical question

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• posted on March 14, 2007, 10:10 pm
I have to run a 220v 14amp line about 15 ft. Will a line of 14/2 work or will there be a problem with the wire getting too hot? The motor says it pulls 11amps.
Thanks Jimmy
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<%-name%>
• posted on March 14, 2007, 10:18 pm

For most residential wiring applications, NEC says No. 14 = 15 amps No. 12 = 20 amps No. 10 = 30 amps
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<%-name%>
• posted on March 14, 2007, 10:57 pm
The small price difference between 14 gauge and 12 gauge for that short of a run, I would run the 12 gauge. Sounds like there is about a 3 hp motor at the end of this. Speculation would be a table saw. If the guess is correct the "extra" wire gauge would be the better bet. Good luck

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<%-name%>
• posted on March 14, 2007, 10:58 pm
Jimmy wrote:

14 gauge wire is rated for a max of 15 amps. As long as you use a 15 amp breaker/fuse it will be safe.
--
Jack Novak
Buffalo, NY - USA
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<%-name%>
• posted on March 14, 2007, 11:42 pm
Jimmy wrote: > I have to run a 220v 14amp line about 15 ft. Will a line of 14/2 work or > will there be a problem with the wire getting too hot? The motor says it > pulls 11amps.
Wire is CHEAP by comparison to other thing electrical including the cost of electricity.
#14 AWG will handle it legally; however, the line drop introduced by using a small wire #14 AWG) will bite you in the ass every month when the electricity bill hits your door step because you have to pay for all that wasted power caused by using a small wire at high load.
Buy a 10-2 with ground, molded cord set, 25 ft long, chop off the ends, and rewire as necessary.
It is the lowest cost solution available, trust me.
Have fun.
Lew
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<%-name%>
• posted on March 15, 2007, 12:18 am
[schnipf]

..won't the voltages leak out when you cut it?
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<%-name%>
• posted on March 15, 2007, 12:38 am
Robatoy wrote:

More likely that it will spray all over the place at 220v. Lotsa pressure there. Probably even duct tape wouldn't hold it back.
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<%-name%>
• posted on March 15, 2007, 1:21 am
wrote:

Even though duct tape is shiny?
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<%-name%>
• posted on March 15, 2007, 1:32 am
Robatoy wrote:

No chance. That shiny surface is slick. Less resistance, the little volty things will really fly!
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<%-name%>
• posted on March 15, 2007, 4:03 am
wrote:

Wowsers, that electricality stuff sure is complex.
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<%-name%>
• posted on March 15, 2007, 4:17 am

Sure is. With AC, you're paying for the same electrons to flow back and forth through your appliances. Edison was right, alternating current is a ripoff.
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<%-name%>
• posted on March 18, 2007, 11:28 am
i thought electron was a campain poster for a guy by the name of ron. that explains the smoke, them guy's are in there smokin wacky weed jus like them old hippy comy dope feens not only that but they must be gay cause they go both ways
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<%-name%>
• posted on March 18, 2007, 5:41 pm
On Mar 18, 7:28 am, snipped-for-privacy@webtv.net (Ross Hebeisen) wrote: [snip]

Gays go one way....seldom both, because that would make them bi. Cheney's daughter wouldn't be caught dead with a man. (Of course she never had one around her to look up to either.)
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<%-name%>
• posted on March 15, 2007, 3:03 am
Not to worry about the volts, it's the smoke leaking out that causes problems. Poorly wired or insulated wire often leaks smoke which causes a myriad of problems.
Paul
wrote:

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<%-name%>
• posted on March 15, 2007, 4:04 am

But, but.. isn't that the stuff that browns my toast in the morning?
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<%-name%>
• posted on March 15, 2007, 4:27 am

The voltage drop cause by running a 240v 11a max motor over 15' of #14 is too trivial to consider.

OP, if you have #14, use it. If you have both (or neither) use #12 since the price difference is small and you might want a 20a circuit there some day.
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<%-name%>
• posted on March 15, 2007, 5:27 am
Toller wrote:
Why do you say that?
Lew
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<%-name%>
• posted on March 16, 2007, 4:11 pm

The OP doesn't exactly specify whether he's running a permanent circuit or an "extension" cord. For an extension cord, Lew's suggestion is fine, and even 12AWG would be fine for that distance (and easier to find). A year or so ago, HF had 25' 12 AWG extention cords for something like \$7. I bought four of them because it was cheaper than the raw cable price.
For a permanent circuit installation, it would indeed be a joke (and a code violation) to use cable from a molded cord set.
To the OP:
In ANY case, you must size the wire to the distance, load, and acceptable voltage drop. In figuring the distance, you must include the desired extension cord, the lead that's wired into the tool, and the wiring in the wall all the way back to the breaker panel. If you're running a permanent circuit, you need to do it according to code for a 220V 15A circuit (or larger if you want to have overhead for the future - RECOMMENDED)
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<%-name%>
• posted on March 16, 2007, 7:29 pm

Sorry Lew, but I get suspicious when somebody says "trust me". Normally, I would let this one slide. After all, the worst that might happen if he follows your advice is that he might spend an extra few bucks on wire. But it's a slow day at the office, so I decided to run some numbers.
1. A 25 ft. 10-3 extension cord costs about \$25.00 say \$1.00 per foot. 2. 14-2 w/g Romex costs about \$0.27 cents a foot 3. The difference of \$0.73 per foot x 15 feet equals a materials cost difference of \$10.95 for the job.
4. #14 wire has a resistance of about 0.00258 ohms per foot 5. #10 wire has a resistance of about 0.00120 ohms per foot 6. 0.00138 ohms difference x 30 foot total run equals 0.0414 ohms difference in resistance between the two proposed types of wire.
7. The power lost in a wire equals the current (squared) x resistance. At 11 amps load, the difference in power lost is 0.0414 x 11(squared) equals 5.01 watts. 8. The national average for electricity cost is about \$0.10 per kilowatt-hour or \$0.0001per watt-hour. 9. The time required to recoup the initial investment in wire is \$10.95/(\$0.0001 x 5.01) equals 21,856 hours at full load. 10. At an average of 10 hours per week at full load, it will only take him 42 years to recoup his investment. After that, it's all gravy.
DonkeyHody "In theory, theory and practice are the same, but in practice, they are not."
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<%-name%>
• posted on March 17, 2007, 6:51 am
DonkeyHody wrote:
> > Sorry Lew, but I get suspicious when somebody says "trust me". > Normally, I would let this one slide. After all, the worst that might > happen if he follows your advice is that he might spend an extra few > bucks on wire. But it's a slow day at the office, so I decided to run > some numbers. > > 1. A 25 ft. 10-3 extension cord costs about \$25.00 say \$1.00 per > foot. > 2. 14-2 w/g Romex costs about \$0.27 cents a foot > 3. The difference of \$0.73 per foot x 15 feet equals a materials cost > difference of \$10.95 for the job. > > 4. #14 wire has a resistance of about 0.00258 ohms per foot > 5. #10 wire has a resistance of about 0.00120 ohms per foot > 6. 0.00138 ohms difference x 30 foot total run equals 0.0414 ohms > difference in resistance between the two proposed types of wire. > > 7. The power lost in a wire equals the current (squared) x > resistance. At 11 amps load, the difference in power lost is 0.0414 x > 11(squared) equals 5.01 watts. > 8. The national average for electricity cost is about \$0.10 per > kilowatt-hour or \$0.0001per watt-hour. > 9. The time required to recoup the initial investment in wire is > \$10.95/(\$0.0001 x 5.01) equals 21,856 hours at full load. > 10. At an average of 10 hours per week at full load, it will only > take him 42 years to recoup his investment. After that, it's all > gravy.
A little knowledge and some extra time on your hands can produce some interesting results<G>.
Let's take it from the top.
No one has defined the application so we don't know if this is a case where a cord out in an exposed area or conductors in a secure space such as in a conduit or behind a wall are required.
If it is a cord application, then Romex would not be appropriate.
If it is a set of conductors in a secure space, then the cord would not be appropriate.
In either case, any attempt at comparison between the two would be moot.
BTW, if you are aware of what is happening in the raw materials market these days, especially copper which has a history of being volatile, you would also be aware that only a fool would quote anything but "price in effect at time of shipment", and that includes the lowly hardware store down the street that is going to cut a piece of something off a roll that was purchased 6-9 months ago.
Never sold wire but was around the business. Not uncommon to have a price on wire be good only for the day, sometimes two.
Electrical contractors typically make a buy on wire on a job as a specific commodity, just like the apparatus or the lighting.
As far as the cost of power is concerned, think you will find the residential/small commercial market is somewhere around \$0.15-\$0.17/KWH unless it is being subsidized in some fashion.
The days of \$0.10/KWH disappeared with the buggy whip.
Now, let's talk about line losses.
Line losses are a two edged sword.
First, you pay for the lost power and turn it into heat. Heating up a conductor raises the temperature of the insulation around the conductors, thus shortening the insulation life.
2nd, the line losses reduce the amount of power delivered to the load by reducing the voltage at the terminals of the load, which in this case would appear to be a saw or an air compressor.
Reducing the voltage delivered requires that the current be increased to get the same amount of work done.
Again, increasing the current in the motor windings, increases the heat, which reduces the life of the insulation of the motor.
Calculation of the economics is based on the ability of the buyer to get a deal; however, the bottom line when it comes to electrical conductors is that bigger is better when it comes to distribution conductors.
Trust me<G>
Lew