Air Compressor reserve tanks

[79XS11F]

A TWIST on the electrial hook up.

OK .. The compressor says 15 AMP, 208 - 230 VOLT (+ / - 10%) 60 HZ, PH 1
I was under the impression that it would hook up just like a dryer but that's not the case. I took the wiring hook up cover off the unit to attach the dryer type plug and this is not a 3 wire + ground set up. It's a 2 wire + ground set up so now I'm really not sure how to hook it up. How the hell do I get the 208 - 230 VOLTS on 15 AMPS on a 2 wire hook up?
Any help would be very handy in deed.
Rob

[fredintoon]

Hi Rob,
the dryer uses 110V and 220V power and needs a 4-pin (3 live pin plus ground) plug & socket to work. You can use a dryer plug with 3-wire cable to run 220V to your compressor just fine. Simply find which two of the three live terminals have 220V between them, hook your two hot wires to them and be sure the ground wire actually grounds. Remember, 220V can kill you real easy. Know what you are doing or hire an expert.

[Ken Talbot]

I wouldn't try this myself either, but This link talks about how a dryer plug delivers both 110 and 220 to a dryer.

Interesting...

[DiverRay]

Rob,
Ken may be able to help with the search, but I think you need to have the two "hot" wires, Red and Black, connected to the power, with the "Neutral" on the "ground". The fourth, "ground" should be connected to the steel ground on the compressor as well.
In most breaker boxes, the neutral and ground wires are connected to the box frame. YMMV, Check Your Local Codes, etc. etc. etc.....

[79XS11F]

Maybe a look at the way the AC is hooked up is the thing to do . I know it took 2 - 15 amp breakers and it is a 2 wire hook up. The motor in the AC unit it easily the same size if not bigger. I'll post when I figure it out . What I did learn yesterday is that I can not use a selector switch even if I wanted to because the code says that the wire from the panel to the dryer plug MUST be one unbroken continuous run. I do need to do this to code to cover my ass should I ever have a fire. Even if a non code hook up was not the fault of a fire it could throw doubt into an insurance claim.
Rob

[fredintoon]

- - - I do need to do this to code to cover my ass should I ever have a fire. Even if a non code hook up was not the fault of a fire it could throw doubt into an insurance claim.

>
Hi Rob,
I swear I posted that very thing about 2 pages back.
What I did for 12 years was to unplug the dryer and plug in a fat extension cord that took the 220V out to the garage.
Then when I got more 220V stuff I had a professional electrician install an extra breaker in my service panel and wire the garage properly.
As your service panel has no room for another breaker you are SOL there so, two options:-
1) Put up with the inconvenience of an extension cord from the dryer plug.
2) Install a bigger service panel and wire the garage to code.

[79XS11F]

Yes I did read that post and I was ready to hook up like the dryer BUT the issue is that the dryer is a 3 wire (black, red & white) + ground set up and the compressor is a 2 wire (black white) + ground set up. So it's not the same set up as the dryer.
Rob

[blue giant]

Rob,

It's the same as you're air conditioning. For now disconnect the A/C and connect the compressor to the A/C breaker.

Paul

[Rasputin]

panel

You may not have room in your house panel to facilitate another breaker. In this case a sub-panel can be installed depending on the amperage load of your power line into the house and main breaker. You should be able to run a sub-panel off the main panel and by changing a couple of breakers get what you need. I would sincerely urge you to get an electrician to look at it. That way you will be fully aware of all the possibilities. Loads of electricians will give free estimates (in hope of getting your work) and tell you what you need for safety and to meet code. The last thing you need is a fire or worse due to attempting something that may be best left for a pro. JAT

[yadada]

I remember this problem now! Since I have exactly the same compressor I had the same problem. I was expecting the four wire hook up and then the thing only had three! I'd forgotten about this. I think I just used a 15 amp double pole breaker and put the uninsulated wire from the green screw to the ground bar in the panel. I'll have to look to see what I did. Mine isn't to code, yet. Right now the cover is off the breaker panel and I just have the wire directly between the two...since they are so close to each other and all. That's a good project for this weekend, fix the wiring!

[fredintoon]

Not an issue

Yes I did read that post and I was ready to hook up like the dryer BUT the issue is that the dryer is a 3 wire (black, red & white) + ground set up and the compressor is a 2 wire (black white) + ground set up. So it's not the same set up as the dryer.
Rob

Hi Rob,
set your multimeter to AC Voltage at a range greater than 220V.
Shove the probes into the different slots in the dryer outlet.
You are looking for the two slots that have 220V between them.
Connect the black & white wires of a sufficient length of 3-wire extension cable to those particular pins on a new dryer plug, plus connecting the green wire to the grounding pin.
Wire a short cord to the compressor motor and buy a sufficient amperage 220V plug & socket to join the long & short cords together.
And as always, be careful when messing with electricity.

[ELDR]

Hey Rob

If your dryer plug is to code Red and Black are the wires to use. Should be 220-240 AC between them. White is always neutral. Ground is Ground.

[79XS11F]

Hey Rob

If your dryer plug is to code Red and Black are the wires to use. Should be 220-240 AC between them. White is always neutral. Ground is Ground.

That's what I was also thinking. on a dryer each of the red and blacks carry 110 volts, white is natural and ground is ground. Now my AC is a 2 wire set up that uses 2 - 15 amp breakers so I am betting the set up would be the same for the compressor. I can't see splicing the black and red together and the 2 whites together to create 220 volts and in any case it would still be over 30 amps which would not flip if there was to be an over draw on the line.
Rob

[fredintoon]

I can't see splicing the black and red together and the 2 whites together to create 220 volts and in any case it would still be over 30 amps which would not flip if there was to be an over draw on the line.

Hi Rob,
if you splice the black and red wires together you will get a 220V dead short.
This is not a good thing.
There are 4 wires in the dryer outlet plug; red, black, white, green.
There will be 3 wires in the extension cord you are going to make to take the 220V to the compressor ; black, white, green.
Wire the extension cord into a new dryer plug like this:-
Take the original dryer plug's cover off to see which color of wire goes to which prong.
Connect the new cord's black wire to the same prong the dryer's black wire goes to.
Connect the new cord's white wire to the same prong the dryer's red wire goes to.
Connect the new cord's green wire to the same prong the dryer's green wire goes to.
The new plug's fourth prong is not connected to anything.
You can connect the other end of the cord direct to the pressure switch on the compressor or you can run a shorter cable from the compressor and use a welding plug & socket to join the two in your garage.

[ELDR]

Fred is correct, follow his notes and all should work.

The White is not used in a 220 only appliance. Some appliances like a dryer and stove also use the neutral wire because they also have internal 110VAC components like timer motors or in the case of a dryer the spin motor is 110VAC while the heating coil is 220VAC

Two Breakers are required for safety as the metal body of the compressor is grounded. Ground is at the same potential as neutral and a accidental short from either Red or Black leads to ground will cause the breaker to trip protecting the user (you) from a shock. The breakers are usually tied together so if one trips the other also trips fully disconnecting power.

Ted