3 way, 220v switching

[The Car Man]

I want to control a 50 amp 220v curcuit from two locations. I understand that this could be done with a contactor...or I think it can.

I would rather use a 120v coil than a 24v coil for the switches, but it's no big deal. I just did this with a 120v curcuit and a 24v coil via a HVAC fan controller, so I understand the concept.

Can someone tell me what is the contactor I need? I mean, I can't seem to find anything to switch 220v. I am going to use this for an air compressor located in the basement for a basement shop and in the garage, wanting to turn the compressor on/off from either location. (I would leave the compressor "live" and turn it off with these "wall" switches.....like turning the lights on at either end of a hallway).

A link to the right contactor would be great.

Thanks. Great forum!

 

[pattenp]

Here's a contactor with a 120v coil,

http://americanhvacparts.com/Mercha...duct_Code=CTR502P120S&Category_Code=c1-120v2p

 

[mrb]

i have a few 3p 50 amp contactors if you cant find one cheap. ideally you want to do this with start / stop buttons and indicator lights vs controlling it with toggle switches. ill post a diagram for you but wont have time until tomorrow night. Why do you want 120v control vs 24v control?

 

[The Car Man]

Just didn't want to mess with a transformer with the 24v, but I could be talked into it.

I would appreciate the diagram.....maybe I'm just having brain gas.

Yeah, I'd like to get away cheap if I can.....waddaya got?

Thanks

 

[mrb]

Just didn't want to mess with a transformer with the 24v, but I could be talked into it.

I would appreciate the diagram.....maybe I'm just having brain gas.

Yeah, I'd like to get away cheap if I can.....waddaya got?

Thanks

ill check, i know i have contactors (120v coil, then you use an ice cube relay to switch that with 24v) pilot lights, some buttons. ill see what all ive got.

you *could* do it with a pair of 3 way switches as you proposed, but the other way is better. what kind of distance are you looking at. the cost of some 14/3 for your control circuit might pay for the transformer and other stuff...

 

[The Car Man]

I have enough 10/2 and 14/2 left over from other stuff to wire it all up, so that's covered. I ran 8/3 from the main for about 30 feet to the compressor. The switches only have runs of about 10' each......got lucky on the placement of the compressor, with my basement workshop in the next room and the garage right above the compressor.

I wish I had of thought of the welder, bigger compressor, dust collector and four pole lift BEFORE the house was built! I did go with a 400 amp service though.

My wife let me get away with two man caves.....upper and lower levels.

Thanks again.

 

[Norcal]

Here's a contactor with a 120v coil,

http://americanhvacparts.com/Mercha...duct_Code=CTR502P120S&Category_Code=c1-120v2p

You do understand definite purpose contactors are not UL listed? They are UL recognized but that does not mean they can be used for site assembled projects, with out testing by UL or other NRTL, Nationally Recognized Testing Lab. & doubt anyone has a spare $100K or so around to have the testing done.


Edit: Their use in HVAC equipment has been engineered & tested for the specific application.

 

[Alchymist]

Use an impulse relay with a 24 volt coil to control a contactor at the load. Low voltage push buttons can be located anywhere needed. Push once to turn on, push again to turn off.


https://www.relayspec.com/catalogs/026940/105A_385.pdf

 

[The Car Man]

Hmmmmmm.....guess I need to rethink this?

Guess that is what "definite purpose" means, huh.

 

[mrb]

Hmmmmmm.....guess I need to rethink this?

Guess that is what "definite purpose" means, huh.

you can get ul contactors, just cant use a definite purpose one.

i will admit to using them, to control 9kw of lighting nonetheless (this is the last thing you would use this type of contactor for i believe) it only had to work once. i took one of the contactors apart afterward to look at the contacts and they were in very good shape compared to what i expected.

 

[Mr_fixit]

How about a different method. I use a remote control to open a solenoid valve after the compresor. You could wire it to operate ofas switch if you like. So I leave my big garage compresor on all the time and have iit feed back into the cellar, and small garage,. I'm using the wireless X10 devices to do it.... from the house or garage. Click. Instant air. You can ge them in 12 v 120v, 24v, probably more. They only use about 8 watts when th air is on.

 

[pattenp]

You do understand definite purpose contactors are not UL listed? They are UL recognized but that does not mean they can be used for site assembled projects, with out testing by UL or other NRTL, Nationally Recognized Testing Lab. & doubt anyone has a spare $100K or so around to have the testing done.


Edit: Their use in HVAC equipment has been engineered & tested for the specific application.

The overview of this contactor on the below linked site shows this Square-D contactor as UL approved. It also list the contactor as having other uses than just HVAC.
http://www.alliedelec.com/search/productdetail.aspx?SKU=4280076#tab=Overview

 

[The Car Man]

Thanks for all of the great replies.

Mr Fix It,
Leaving it on all of the time is not an option because it's gonna be in the house basement and my marriage wouldn't survive. Too many year invested in that relationship to risk it.

Pattenp,
I wonder what exactly "definate purpose" means....must not mean "specific" purpose if can be multi-purpose?

Norcal,
I asked an electricion buddy of mine a while back and he specifically mentioned using a contactor. He is also an insurance investigator for electrical fires. I guess that I will give him a call......and maybe just pay him to do this!

MRB,
I would like to see that diagram if you get a chance.

I just can't believe that I can't find a more definative answer. Thanks again to all.....if someone figures it out, please let me know.

 

[mrb]

im not going to have time for diagram until tomorrow probably

to just use a pair of 3 way switches, you will wire them same as you would a light, and connect them to the coil of a 120v coil 2 pole 50 amp contactor. depending on whether this control circuit is protected by a 15 amp or 20 amp breaker you will need 14/3 or 12/3 to each switch.

 

[pattenp]

Definite purpose contactors are designed mainly for HVAC applications but are used in other applications. The main thing is to size the contactor correctly to the application as being used. You need to size it for the max amp load and duty cycle. As an example the Square-D 8910DPA52V02 has a max amp load rating of 50A and an electrical life of 200,000 cycles and a mechanical life of 500,000 cycles and the duty cycle is continuous. This contactor will work for what you are planning to do, although it's a bit pricey.

PS - The first contactor I posted actually only has a 40 amp full load rating.

 

[jbekuykendall]

I have a need to remotely switch the following:

ELECTRICAL
REQUIREMENTS
230 VAC, 4-Wire,
50 AMP, 60 Hz
GFCI Protected
Dedicated Separate Circuit

Using a Belkin Wemo Maker - http://www.belkin.com/us/wemo-maker/

So 220 - 50 amps -> solenoid (unknown) -> Wemo low volt switch -> breaker box - dedicated circuit. Anyone know how best to direct me on my quest?

 

[wyliesdiesels]

If youre using this to switch a compressor, the contacor needs to be sized by the HP of the motor not just the amps! So how many HP is your compressor? And why not just use 3-way switches to switch one side of the contactor on the starter which Im assuming your compressor has. The other side of the contactor coil should be fed by the overloads. Obviously the control circuit will need its own fuse for the wire.

Dont forget a disconnect unless the compressor is within sight and 50' or less from the electrical panel.