Help me rig 'er up


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Old 11-23-07, 06:30 PM
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Help me rig 'er up

I know this won't be to code, but this is just a temporary setup.

I'm building a garage about 800 feet from my current home, hence from the service panel. I want to run my compressor which is 7.5amp @ 220v, but I'm sure it's startup amperage is higher. Here's what I'm thinking of doing:

I want to run 12-2 wire that I will be using in the garage anyway, so I'll just buy a spool and get within 200' of the garage, say a 600' run (could be more, haven't measured exactly yet). I'll wire a dedicated circuit on my service panel, 20amp 220V, but the problem is the voltage drop will be significant. I've calculated it to be about 25V drop with this setup, maybe more. I know getting larger wire would help this problem, but larger wire is expensive and I don't have any use for it later. Since I need the 12-2 later anyway, it is essentially free.

Can I run 2 12-2 wires in parallel to increase my capacity? In other words, run 4 conductors, 2 for each 120V leg of the 240V circuit. Then each wire will be carrying 1/2 the amperage and I should get less voltage drop. But if the wires are slightly different lengths, will the phase get off kilter when I reconnect them at the 600' plug? It seems like it should work to me, but I've never heard of anybody doing this.

Thanks in advance,
Jon
 
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Old 11-23-07, 09:13 PM
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The reason you have not heard anyone doing this is because it probably wont work. One reason is because to parallel #12 is a code violation. Another is that you will get about an 80 volt drop when the compressor starts or tries to start. Are you going to just lay the cable on the ground? Thats a no no.
 
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Old 11-23-07, 10:08 PM
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As I said, temporary

Basically, I am using 12-2 wire as an extension cord. This is just temporary. I've talked with an electrician about the length of the run, and he thinks just one 12-2 wire will probably work. I may just have to shorten the length a bit until it does.

The question is can you use two wires in parallel to simulate one larger capacity wire.
 
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Old 11-23-07, 11:05 PM
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Temporary installations still need to comply with all codes and nothing smaller than one-aught (0) conductors are allowed to be paralleled.
 
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Old 11-23-07, 11:13 PM
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Why? Will something go wrong if you parallel a smaller wire?
 
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Old 11-24-07, 05:21 AM
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You want us to advise and bless something like this?

Do it properly or do not do it at all.
 
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Old 11-24-07, 05:50 AM
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Originally Posted by jrlogan1 View Post
I've talked with an electrician about the length of the run, and he thinks just one 12-2 wire will probably work. .
apparently you have not talked to an electrician, or one that knows anything. Whatever he is, he knows not of what he speaks.




Helping you install this extremely poor idea goes beyond a severe code violation, it goes against the morals and ethics we have that guides us to do the right thing.

You want to do this right and not have to buy the correct wire?

buy a generator.

even paralleled without considering the inrush current, the wire is still too small
 
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Old 11-24-07, 06:44 AM
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Wow. Is this an electric forum or the ethics police?

Let me rephrase what I am doing. I am going to run a dedicated 20amp 220 circuit off my service panel, perfectly to code, to a junction box that has a 20 amp plug. Now I need a really long extension cord. My idea was to try and use 12-2 instead of regular cords because it will work much better. Or does using a long extension cord violate some other code? As I said, this is temporary. I need this compressor to work for a few days, that's it.

And to you nap, you ought to be ashamed:

'apparently you have not talked to an electrician'

Are you suggesting that I'm lying? Are you guys here to help or to berate people asking questions? Why in the #@@#$ would I lie? And by the way, morals and ethics have nothing to do with this. Good morals/ethics would include not insulting other people. Get a dictionary.

So I went out this morning and bought 1000' of 12-2, put a plug on one end and hooked the compressor to the other, leaving it spooled just to test it. I must admit I'm surprised, but it worked just fine, even at 1000'. While running under load I was pulling about 10 amps and at 230V (250 at the plug). Startup peaked at 20 amps. Seems my electrician friend, whos name is Worthy, and yes, he does exist, knows exactly of what he speaks.

I looked elsewhere and found the following answer myself. Yes, you can parallel 2 #12 wires and increase your capacity. In fact, another forum was even siting the specific codes that allow paralleling these wires.

Posting on this forum has been an unpleasant experience, and a waste of time. What is your guys' deal?
 
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Old 11-24-07, 07:06 AM
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You want us to believe you? Post the site and code section.
-----------------------

using #12 and your length of 1000 feet and your running current of 10 amps, you would have 202 volts at the compressor. Under start at 20 amps, you would drop to 164 volts.

We have all been doing this long enough to know what those numbers mean and what would happen.

This is where I say:

prove it.
 
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Old 11-24-07, 07:35 AM
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Old 11-24-07, 08:04 AM
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Using 12-2 cable as an extension cord violates code, and is dangerous.

Doing so is very foolish, even temporarily.

This is a do it yourself board. But we do not help people do things that could kill them.
 
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Old 11-24-07, 09:13 AM
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Deleted my post. Decided wasn't going to make a difference.
 
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Old 11-24-07, 01:15 PM
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Old 11-24-07, 01:22 PM
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Old 11-24-07, 01:27 PM
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Old 11-24-07, 02:22 PM
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Oh, it works. Well then, everything's fine, right?

This is typical of how someone comes looking for a certain answer, and when they don't get the answer they want to hear they get all defensive.

Also,I wouldn't go quoting Mike Holt's site when you have NO clue about what you are looking at.
 
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Old 11-24-07, 02:57 PM
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Wow. Unbelievable.

Go back and read the whole thread.

I've asked a few simple questions. How many answers have I gotten that actually address my questions? Go ahead, count 'em. 0.

Hence, a waste of time.

Oh, and how many times have I been insulted and had my honesty challenged? I don't feel like counting, but you'd think I assaulted somebody the ways you guys are responding.
 
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Old 11-24-07, 03:08 PM
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logan; YOU need to go back and read mile holts web thread. The arguement does NOT state you situation is ok. They are argueing over a control circuit (which does fall within an exception but only with many other qualifiers) or a redundant circuit, which your is not either.

You just don;t get it. Although a 20 amp breaker is enough for your circuit, whith the voltage drop, the current needed to run the circuit will increase, which will produce heat. then end result is it will not work correctly. If it works at all, it will result in a smoked motor in chort order so, if you want to do it, go for it. Its not my motor that will smoke.
 
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Old 11-24-07, 03:13 PM
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Originally Posted by jrlogan1 View Post
Your calculations and statements all have one common problem. They are at odds with reality. .
if you think physics has nothing to do with reality, then you might be right but those calulations are based upon the principles of physics, which unless something happened very recently, cannot be broken.

One more thing; the code does not require upsizing wire for voltage drop. That is from a practical point of view. You can wire something that causes a 100% voltage drop if you want. That does not mean it will work, but hey, it's your motor.
 
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Old 11-24-07, 03:45 PM
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Originally Posted by jrlogan1 View Post
....., but you'd think I assaulted somebody the ways you guys are responding.
If you do something OBVIOUSLY against code, and do it without regard for the code and for safety, and someone gets hurt, that IS equal to assault.
Maybe we are all trying to avoid someone getting hurt and in turn your feelings got hurt.
 
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Old 11-24-07, 04:43 PM
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Aside from code, Yes it will work, as it probably does......

But.. When the simplest of mishaps occurs, You have a 600 foot "FIRESTICK" aimed directly at your main panel. No way in hell can you out run it, or disconnect it before it does some major damage. Temporary or not , I dont think your WIRE is gonna care much about that, Because it doesnt know the difference.

As far as code, even with 1/0 , "The wiring must rated to carry the full load of the Circuit with only one leg connected".

There is also a big difference in "Start-up" current from empty as opposed to "TOP-OFF". A single 12 gauge cable is TOAST under that condition, And for your own safety , just take my word for it.
Consider that if this was a Light bulb, no prob, But its an electric motor, running on quite considerable voltage and amperage,...
 
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Old 11-24-07, 04:49 PM
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Originally Posted by nap View Post
logan; YOU need to go back and read mile holts web thread. The arguement does NOT state you situation is ok. They are argueing over a control circuit (which does fall within an exception but only with many other qualifiers) or a redundant circuit, which your is not either.

You just don;t get it. Although a 20 amp breaker is enough for your circuit, whith the voltage drop, the current needed to run the circuit will increase, which will produce heat. then end result is it will not work correctly. If it works at all, it will result in a smoked motor in chort order so, if you want to do it, go for it. Its not my motor that will smoke.

Man, I can do this all day. You need to actually read what I write. I said that his thread supports the fact that two wires in parallel increases capacity. Which is does. I didn't say it meant everything I'm doing is kosher.

#2
Of course if you get voltage drop, the amperage goes up and you get more heat, and that's hard on a motor. You're teaching me nothing. Known that for years. But my voltmeter says I have 230 volts which won't hurt a thing. And my amperage is within the amp rating of my circuit. So it sounds to me that my circuit is fine, the only issue is the wire being exposed. And I've already considered it might be hard on my motor, I don't care. This has nothing to do with your previous worthless comments on the subject.
 
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Old 11-24-07, 05:04 PM
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Originally Posted by Unclediezel View Post
Aside from code, Yes it will work, as it probably does......

But.. When the simplest of mishaps occurs, You have a 600 foot "FIRESTICK" aimed directly at your main panel. No way in hell can you out run it, or disconnect it before it does some major damage. Temporary or not , I dont think your WIRE is gonna care much about that, Because it doesnt know the difference.

As far as code, even with 1/0 , "The wiring must rated to carry the full load of the Circuit with only one leg connected".

There is also a big difference in "Start-up" current from empty as opposed to "TOP-OFF". A single 12 gauge cable is TOAST under that condition, And for your own safety , just take my word for it.
Consider that if this was a Light bulb, no prob, But its an electric motor, running on quite considerable voltage and amperage,...
Hey! A real answer! Thanks for actually considering the situation. So I'm confused. If my peak amperage is 20 amps, then I only need one 12-2 wire to be within code, yes? I'm not going to parallel the wires if I don't need to, which it seems I don't, as it's working just fine with one. I only hit 20 amps in one of about 10 readings, and that just for a blip of the digital readout. Most startups were more like 17 amps, and like I said, it runs at 10 amps the rest of the time. So the wire size is ok, no? (All of my tests have been with one single 12-2 wire)

Firestick? Are you saying I have a fire hazard? I am planning on running the wire through 3/4" PVC conduit. What do I need to do to remedy this?
By the way, my buddy told me to get an arc fault breaker for the circuit, which I already plan to do.

Finally, (and I can already hear people calling me a liar again), I live in a rural area that doesn't have building codes. We don't need permits, we don't get inspections. There's no legal issue here. No, I'm not lying, this is true.
 
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Old 11-24-07, 05:16 PM
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In theory that compressor should have "Dragged it self" to an early death almost instantly.

Ultimately, a Service for the garage will be necessary, and since you can only have ONE "FEEDER " to an outbuilding, I would think 12/2 would be "OutGrown" rather quickly. Since the distance is so large, I would carefully lay out what you want for the end result, and work around that, as opposed to buildng a temp situation, and having it be useless before its started.
 
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Old 11-24-07, 05:35 PM
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If my peak amperage is 20 amps, then I only need one 12-2 wire to be within code, yes?
yep, all you need is one 12/2 wire. there is nothing in the code requiring anything more.

Since you don't care about the code, why would you even care what the code requires.

I said that his thread supports the fact that two wires in parallel increases capacity.
of courese it does. Nobody EVER claimed anything to the contrary. Everybody here was simply telling you that it is against code.
If you want, you could run 15 cat 5 cables out there and do what you are doing. it's against code but it would work. The point everybody was dealing with is the legality of the install. Due to that, nobody wants to tell you how to smoke your motor.

By the way, my buddy told me to get an arc fault breaker for the circuit, which I already plan to do.
Yep, Worthy surely is a good electrician. Apparently has no idea what an arc-fault breaker is for and where it is required.

Yep, surely knows his stuff.
 
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Old 11-24-07, 06:36 PM
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Old 11-24-07, 07:06 PM
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Old 11-24-07, 07:36 PM
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There are many knowledgeable people on this board, many of which ARE proffessional electricians.

I on the other hand am just a Humble auto mechanic, from a backwoods lil town in Pa.

I dont think anyone meant any Ill will towards you, But what you proposed was extremely unsafe.

Nobody can tell you you cant do it, But waking to a flaming fuse panel isnt exactly anyones decision either.

Just think carefully before you do anything, It may be your families lives at stake if youre wrong.
 
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Old 11-24-07, 07:44 PM
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Old 11-24-07, 07:50 PM
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Old 11-24-07, 08:25 PM
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Old 11-24-07, 08:33 PM
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Cost of wire

I am really curious as to the cost of wire vs buying a generator.

Lets say 1000ft of wire 500.
Ground fault 20.
Arc breaker 40.
Buying PVC

I think it would be cheaper to buy a generator or rent one.

BOB
 
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Old 11-24-07, 08:49 PM
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Originally Posted by mrboyd View Post
I am really curious as to the cost of wire vs buying a generator.

Lets say 1000ft of wire 500.
Ground fault 20.
Arc breaker 40.
Buying PVC

I think it would be cheaper to buy a generator or rent one.

BOB
I need the wire anyway for the garage I am building and the house I will build next year, so it's essentially free. It cost $268 for 1000'.
Ground fault I already have. PVC I already have.
 
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Old 11-24-07, 09:52 PM
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268 $???? for 1000 feet????
Double check wire type!!! NM cannot be used outdoors regardless of conduit, And by the way that sounds really cheap even for NM cable.

Will the compressor stay in the garage? With your current setup the compressor along with anything more than a nightlite, will send the whole thing south.

I realize this is temporary, But why would you want the labor and expense of doing this 3 times?
 
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Old 11-25-07, 12:37 AM
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I'm almost scared to reply because of the tongue lashing I will receive.

This is NM wire. This setup is for building the garage, which is currently under construction. I have already buried conduit for real permanent service that will be coming in later, but the power company is going to take too long, so...again...this is a temporary fix to run my compressor that I need to power my framing nailer to finish building my garage. A month or two from now I hope to have a completed garage with new 400amp permanent service that is already in the making, and 90% completed.

I know this isn't to code, but I also know that this kind of thing happens very frequently in the real world. To do this "right" I would have to buy a generator ($600+) or run UF in buried conduit which would be prohibitively expensive. My solution is going to cost me the price of a breaker, as I need the wire for the garage anyway, and I have everything else. Now that I've tested it, I know it will work. I plan to leave the circuit power on only when its in use, and I expect to use it for 1-2 weeks at most.

Finally, this is perfectly legal in my area. There are no building code requirements, permits, or government inspections. We use codes as guidelines here, but we aren't required to stick to them.

Does this clear some things up?
 
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Old 11-25-07, 03:57 AM
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Well ... this thread is fun and refreshing for a change. It seems that physics is indeed at play here: Perpetual force meets immoveable object.

Originally Posted by jrlogan1 View Post
So I went out this morning and bought 1000' of 12-2, put a plug on one end and hooked the compressor to the other, leaving it spooled just to test it.
A 1,000 foot coil of 12/2 is a crude inductor. Somewhere in the back of my brain is a fuzzy detail about air-core inductive ballast devices and their ability to store and limit current. I'm curious to see how the amp & voltage readings change after you stretch it out.
 
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Old 11-25-07, 05:25 AM
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Originally Posted by Rick Johnston View Post
A 1,000 foot coil of 12/2 is a crude inductor.
No, it wouldn't be because of the neutral being in the same coil. Yes, there was some talk about parallel conductors and if one did something like this then you'd have to consider induction.
 
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Old 11-25-07, 05:30 AM
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Originally Posted by Rick Johnston View Post
A 1,000 foot coil of 12/2 is a crude inductor. Somewhere in the back of my brain is a fuzzy detail about air-core inductive ballast devices and their ability to store and limit current. I'm curious to see how the amp & voltage readings change after you stretch it out.
The engineer and I had a discussion about this. He couldn't recall anything about a dual conductor coil, as this is, and what effects that might have. Basically you have two coils in opposite directions, coiling one direction on the black and opposite on the white. We are guessing that they would cancel each other out and not have much induction effect. However, I will definitely check the amps/volts again when I set it up for real (hopefully tomorrow) and I'll post it here, just as a matter of curiosity.
 
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Old 11-25-07, 05:32 AM
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This thread is closed. Your plan is ill thought out, dangerous and a code violation. Don't do it.

Regular electrical cable (NM) is not built to handle the demands of being outdoors. It will get damaged, and then hen you put it into your house it could cause a fire. Buy a proper extension cord. Inside conduit it will quickly become wet and ruined.

Running cables in parallel when they are not designed to be run in parallel (and not done properly) creates electromagnetic fields which create all sorts of problems.

Please give up on your plan before you kill someone. And yes, if you do kill someone (other than yourself) you will go to jail.
 
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Old 11-25-07, 12:18 PM
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In a private message from winnie I received the following. Jon intended to post these but slept on it first, and I had closed the thread before he could post. I have no problems posting this.

1) This is _not_ the place to ask for help if your attitude is 'I don't care about code, only safety.' You kick people by saying that their experience base is essentially irrelevant, and then ask them to respect your questions. Most of the electrical code is not about the bare minimum required to make something work, but instead a reasonable minimum to work, work safely, and continue to be safe even when something goes wrong. The fact that a particular area does not have inspections nor an adopted code does not mean that code is irrelevant to you; in the event of a failure that causes damage or injury, code will be relied upon in the court case.

2) Significant portions of the code are in fact arbitrary, as evidenced by the fact that other countries have _different_ electrical codes, yet they get by just fine. Once you make the decision to deviate from code, you are not necessarily creating an unsafe situation, but rather you are setting yourself up in the position of a testing lab and code making panel; rather than trusting years of experience and results you are charting new ground. Maybe it is safe, maybe not. The point is that you no longer have a safe electrical installation, you have an _experimental_ installation that _may_ be safe.

3) There are almost always code compliant ways to do what one really wants to do, it just requires more thinking. Sometimes it helps if you describe your installation more fully, rather than jumping immediately to 'I don't care about code, tell me how to hack this.'

On to the specific points.

1) Code allows parallel conductors in specific situations. The most well known is to provide circuits with greater amp capacity. Code permits conductors of size 1/0 or larger to be placed in parallel, with a total amp capacity that is the sum of the adjusted capacities of the individual conductors. In other words, you could take two 200A conductors and parallel them and treat the pair as a single 400A conductor. To use this code rule, you have to carefully match the characteristics of the conductors, in terms of material, length, conduit type, termination, etc. so as to make sure that the current flow divides evenly. If the current flow did not divide evenly, then one of the conductors might be overloaded even though the total circuit was not overloaded. Your desire to parallel #12 conductors is in clear violation of this rule.

I then went on to discuss other aspects of his installation, suggesting UF for the underground run (he probably doesn't know that he could use UF in place of NM for the later installation), warning against attaching solid conductors to cord caps, warning against running unprotected cable on the ground, and discussing voltage drop and his compressors.

-Jon
 
 

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