230 question

[uncletater]

I was shopping for a compressor and was talking to the sales person. I was looking at Northern tool at the Puma and the IR.

The Sales person stated that the compressor should be wired within 10 feet of the panel.

Is this true. If so I am screwed because my panel is about 25 feet away from where I want to set the comperssor.

I have yet to wire the 230 yet so my options are open. I am sure my electician will know what to do. I just wanted some opinions before I discuss it with him.

Thoughts?

 

[pattenp]

There is no problem with it being 25' from your panel. The 10' is bull. Just use the correct size wire.

 

[frankush]

The install manual will tell you if you need to upsize the wire. Go to the manufacturer's website and see if an install manual for the models you are looking at can be downloaded.

 

[Falcon67]

Depends on the distance and size of the motor. My 3.2HP upright is 50' from the panel as the wire runs, 12-2 is all that is required to feed the 240VAC motor.

 

[uncletater]

I am looking at a 3hp single stage upright. I have a lot of 12/2 left over from the outlets. I do have 10/3 that I thought could be used for the 230 runs.

 

[Speedy Petey]

I am looking at a 3hp single stage upright. I have a lot of 12/2 left over from the outlets. I do have 10/3 that I thought could be used for the 230 runs.

What does the size of the wire have to do with the voltage? And WHY do you need 3-wire? Isn't this a 240V motor load only?

Run the appropriate size wire for the circuit size, NOT the voltage.
Run the appropriate configuration (2-wire, 3-wire) according to the voltage (120v, 240v, 120/240v).

 

[lessersivad]

What does the size of the wire have to do with the voltage? And WHY do you need 3-wire? Isn't this a 240V motor load only?

Run the appropriate size wire for the circuit size, NOT the voltage.
Run the appropriate configuration (2-wire, 3-wire) according to the voltage (120v, 240v, 120/240v).

Gosh, I guess voltage drop may have something to do with the 1st question.

Along with a possibilty later on that a larger compressor/load MAY come into play.

Also, while 3 wires may not be neccessary, some people actually do run a ground to a 240 volt application.

Just my 2¢.

 

[Speedy Petey]

Gosh, I guess voltage drop may have something to do with the 1st question.

My point was he said he had 12/2 from some receptacles he wired, and that he had 10/3 for the "230". As if #10 were somehow required for a 230V circuit. I don't get how so many people think larger wire is automatically required for a 240V circuit.
I HIGHLY doubt voltage drop was a consideration in this case.

Along with a possibilty later on that a larger compressor/load MAY come into play.

Maybe, but I doubt it.

Also, while 3 wires may not be neccessary, some people actually do run a ground to a 240 volt application.

I don't get it. A ground is ALWAYS required, regardless of the voltage. I was referring to "3-wire", as in 10/3.
This is another DIY/homeowner wives tale. Automatically thinking 3-wire is needed for a 240V circuit. Maybe because they think only black and red can be used. Who knows?

 

[Falcon67]

I am looking at a 3hp single stage upright. I have a lot of 12/2 left over from the outlets. I do have 10/3 that I thought could be used for the 230 runs.

So it's like mine, in which case 12-2 will do fine based on the distance you stated in post #1. If you think you'll upgrade later to something like a 5 or 7.5 HP model, no problem using #10. I have 4 240V runs, only one uses #10. That is the 5kW heater, which pulls 20A. The compressor only pulls about 10A running.

 

[uncletater]

thanks for the answers.

Yes I was thinking of voltage drop may have been an issue.

Yes I thought that you would need to ground 230 (hence the 3 wire)

As you can tell I do not mess with electrical. That is why I asked.

 

[pattenp]

Just a FYI, but when referring to wire such as NM-b (Romex), 12/2 is 2 plus a ground and 12/3 is 3 plus a ground. The ground wire is not included in the count. When talking about cord the ground is included in the conductor count.

 

[uncletater]

Sorry I didn't phrase that correctly.

I assumed with the 230 I would need two hots(blacks or black and red) one neutral (white) and a ground.

This is why I picked up the three wire

 

[Engineer61]

You do need to ground 230, it's the neutral line that you don't need. You only need the neutral line if you want to run something that's 115v off of the compressor switch; fan, hour meter etc. which you would hookup to the hot line that is controlled ny the switch, and the neutral line. The compressor runs between the two hot lines (230v), and 115v is between either of the two hot lines and the neutral line, and the ground line of course is hooked to the compressor's ground.

 

[uncletater]

You do need to ground 230, it's the neutral line that you don't need. You only need the neutral line if you want to run something that's 115v off of the compressor switch; fan, hour meter etc. which you would hookup to the hot line that is controlled ny the switch, and the neutral line. The compressor runs between the two hot lines (230v), and 115v is between either of the two hot lines and the neutral line, and the ground line of course is hooked to the compressor's ground.

thanks this is good information.

 

[lessersivad]

Speedy,

You wrote;
"I don't get it. A ground is ALWAYS required, regardless of the voltage. I was referring to "3-wire", as in 10/3.
This is another DIY/homeowner wives tale. Automatically thinking 3-wire is needed for a 240V circuit. Maybe because they think only black and red can be used. Who knows? "

Yup, you're right, a ground is required and I had a MAJOR brain fart when I wrote previously in regards to the "10/3".

I know what 10/3 is but for some stupid reason I was thinking of only 3 wires, NOT 3 + ground.

So I made a rather BIG mistake with my response concerning the 10/3.

 

[theoldwizard1]

Just a FYI, but when referring to wire such as NM-b (Romex), 12/2 is 2 plus a ground and 12/3 is 3 plus a ground. The ground wire is not included in the count. When talking about cord the ground is included in the conductor count.

Absolutely accurate !


HOWEVER, when you are referring to "portable cordage" (the stuff they make "extension cords" out of) 12-2 does NOT have a 3rd (ground) conductor. 12-3 cordage DOES have 3 conductors.

12-3 cordage (SOW, SJOOW, SJT) can be used to make either a 120V or a 240V only extension cord. Most "modern" 240V "appliances" require 4 wires.

 

[sberry]

Only 230v multi wire appliancs that are common would be ranges and dryers.