is my extension cord bad?

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I haven't tested it, but I was using my air compressor today and I started it up and let it run for about a minute, then my brother came out to yell at me for making too much noise and wondering what I was doing. (He's not mechanically inclined and will never understand) He just likes to look at me like I'm crazy. Well I turned it back on and it just kind of slowly attempted to spin over. Then I let it sit for a few minutes and it turned on fine. Then I tried it again and it did the same thing. There isn't anything visually wrong with the cord. It's not burnt, but it is like 20 years old. I went and used a new extension cord and it fired up normally. Maybe the wiring is worn out causing too much of a voltage drop? It does pull 15amps. Also plugging it directly into the outlet it works great too.
 
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Originally Posted By: motor_oil_madman
I haven't tested it, but I was using my air compressor today and I started it up and let it run for about a minute, then my brother came out to yell at me for making too much noise and wondering what


The highlighted part is the only relevant part. Why does a grown man yell at another grown man?
 
Originally Posted By: bubbatime
Originally Posted By: motor_oil_madman
I haven't tested it, but I was using my air compressor today and I started it up and let it run for about a minute, then my brother came out to yell at me for making too much noise and wondering what


The highlighted part is the only relevant part. Why does a grown man yell at another grown man?


I don't think his brother is a grown man.

/hijack

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It could be that the older extension is not rated to carry the amps, and wasn't letting enough power through once the compressor motor got hot and started to draw more power. Plus, startup loads are higher than running loads on an electric motor.
 
It might not be bad, but it would be bad for your compressor.

Most junk cords are 16 ga, which lets through half the power the compressor needs. 15 amps call for 14 ga at a minimum.

Don't forget your outlet isn't "magic", it can be at the end of 50-75 feet of 14 ga romex inside the walls and the two long runs add up.

Copper's expensive and if one doesn't specifically drop $50 on a "nice" cord with its gauge proudly written all over it with a huge tag, it's a cheapo.
 
PS if you put a power strip on the end of that cord and stick a voltmeter in I bet it goes under 100 volts when the compressor's running.
 
I agree with the above posters: the cord is too long and/or the gauge is too small. Not good for your compressor.
 
Originally Posted By: spasm3
If you try and run it on a long extension of insufficient gauge, you will kill the capacitors.


It was a 14 gauge 50 foot cord. An orange one made by woods. I don't think they make them anymore. I'm pretty sure I've used that cord before, maybe not. Usually I just bring it up to the front porch and plug it directly into the outlet with no extension cord at all.
 
You are better to run more air hose than more extension. 14g on a 50ft run is small if your compressor pulls 15amps.
 
What is the compressor rating?

If it's near 15A, i.e. Something that's not for shooting nails, then you really need some 10Ga cords.

Because my garage is disconnected from my home, and the ampacify of the conductors to the garage is insufficient, I decided to rewire my conpressor with about 50' of 10/2 SJOW (something like that, the 600v rated) cord, and then made another 50' extension cord of the same stuff. The wire is over $1/ft, but is much tougher and you can control your terminations better than an otc 50' 10/2 extension.

All the same, if nothing else, at 50' please go buy a 10ga extension. Harbor freight or Amazon may have better/more selection.
 
They thing probably pulls the same amps as a worm drive SkilSaw.
You need 12Ga at 50ft minimum. At 100ft, you gotta go up to 10Ga.
 
Originally Posted By: eljefino
PS if you put a power strip on the end of that cord and stick a voltmeter in I bet it goes under 100 volts when the compressor's running.


eljefino,
Question: Does the compressor actually need to be running ? ? ?
I'm no Electrician, but I always checked for voltage drop by just plugging a Voltage Meter into outlet or end of long extension cord.

The reason I ask is because I live in a Ranch house that's 50 ft. long.
I recently put in a separate line for my sump pump (dedicated breaker).
New line showed 120 V,,,, but so did the old line.
 
You could have a failed plug. I have a 25' 12/3 power cord just for my portable compressor. Also have a 50' 14/3 I have for general use while working on cars and stuff out in the back. Both recently had the plugs overheat and fail. I replaced them with HD plugs, but that's just silly, having a good HD cord with a low quality plug.
 
Agreed. The owners manual for my compressor indicates that given the choice, you should always use a longer air hose instead of an electrical extension cord, for reasons mentioned in the above posts.
 
Originally Posted By: larryinnewyork
I always checked for voltage drop by just plugging a Voltage Meter into outlet or end of long extension cord.
That won't tell you jack, other than whether the cord has a broken wire.

Voltage drop is a function of current and resistance. If you aren't drawing any current then the open-circuit voltage will read full. Once you start to draw current, the voltage will drop according to the formula E=IR: voltage equals current times resistance, so the greater the current draw and/or the greater the resistance, the higher the voltage drop will be.
 
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