220 volt plug for compressor and welder

[rdsk8ter]

Code says you have to calculate ground fault currents and load currents to correctly size the wire. It also says that each piece of equipment needs to be properly protected. The air compressor is probably not going to use as much current as the welder so you really probably need two outlets not one, but you could get away with one. The outlet needs to be a 30 amp or larger IMO. I have a 50 amp outlet receptacle.

 

Ohm the ground buss to make sure it's grounded and every other bit of advice is correct with the exception of the chicago fire.

funny I have a 30 amp air compressor and a 30 amp welder Ive wired several hundred 30 amp air compressors it is fairly standard. welders you go off the nameplate you only have to do caulcs if its 2 or more welders fed off the same service. a 30 amp circiut requires #10 thhn per 310.16 of the NEC. you will be fine running them both off the one line at seperate times. He is limited to the one outlet due to the rest of the breakers being gfci breakers and no more room on the bus. Adding a sub panel would be a very bad idea here. Get your welder and make sure 30 amps will be good for it( like i said it will say on the nameplate. often found on the back or inside door.)

[srgunz]

What he is saying is the run two seperate 220v circiuts witch is over your skill leven just run the one and plug and un plug whatever you need at the time

 

Yes, what I gathered was he had a 15A 220V and a 30A 220V piece of equipment. That equipment would each have a different plug configuration and cord guage size. Thus he could not just unplug one and plug in the other.

This is why I mentioned a welder breaker and a compressor breaker.

[rdsk8ter]

Yes, what I gathered was he had a 15A 220V and a 30A 220V piece of equipment. That equipment would each have a different plug configuration and cord guage size. Thus he could not just unplug one and plug in the other.

This is why I mentioned a welder breaker and a compressor breaker.

 

I didnt notice that. well that means you need to change a cord witch voids all warrentys or by a small piece of so cord and two cord ends a 30 amp to plug in the outlet and a 15 amp the matches the appliance. You will have to use common sence here and know if the cords nicked or hurt or the appliance is acting wierd unplug it

[Brad-ManQ45]

A 30 amp circuit will be fine for bothe the welder and the compressor.

 

I don't know what kind of compressor you have, but I had to make my own cord for the CH 60 gal. I purchased.

 

I used the 30 amp twist/lock outlet for the 220 outlet in my garage and use it for a 220 vold heater or the welder.

 

My compressor is in the basement (no noise issues) with its own outlet on the same circuit.

 

I don't think changing the plug end would void the warranty on the welder, but you could make an adapter cord easily.

[chrism]

Can't tell what the main panel is rated for. If it is 100 amps then you should be ok. If it is less, you may be overloading the main panel. Just check and see. You have no idea what the other guys are doing in the other stalls. If they are half as crazy as you then your all in for a big surprise.

[mr jdm]

its 100 amps, thanks for the help guys this is great.

[theghosttanker]

It's not too hard to do. Take the front panel off and pull a breaker straight back off the board. Once it's unclipped from the central bus bar and just hanging from it's black wire, it's dead, just loosen the terminal screw to get the wire off. Take the breaker to Home Depot and buy four 15 amp slimline breakers. They will look like skinny versions of what you just took out, and two of them will fit in the same space as a single regular breaker. There are some types/brands of breaker boxes and breakers that will not accept slimline breakers; if you can't find Square D or GE slim breakers that match yours then you are SOL. But most likely you will have no problem. Also buy a twin 220V 20amp breaker, and however much 12 gauge Romex cable you will need, and a box and cover and 220v female receptacle that matches the plugs on your compressor and welder.Also strain reliefs to protect your new cable from the edges of the box you are buying and also where your cable will exit the breaker box. You will need to replace four of the 15 amp breakers in your box with the slimline breakers, leaving a space that the double breaker will fit in. While you have the breakers out of the box, you will see that the central bus bars that the breakers clip to are made so that, as you clip breakers on, they draw power from alternating sides of the central bus bars. These sides of the bus bar carry 110 volts each. Your new 220v double breaker will clip in so that it draws off both of the center bars at once, and will ONLY clip in like this. Connect the black and white wires from your new cable to your new double breaker; pretend the white wire is black and hook it up to one terminal and connect the black to the other terminal.Install the bare copper ground wire from your new cable to the same bar that the other ground wires are connected to. In general, as you work, look at how the electrician installed things and copy it. The only thing you will not copy is that your new white wire will connect to your new double breaker instead of to the bar where the other white wires from the 110 v circuits are connected. Use the strain reliefs just like the electrician did, and staple the cable to the structure just like he did. mount your new receptacle and box wherever you want. You will now have a 220v 20 amp outlet, which will safely run either your compressor or welder, just not both at the same time.

Wiring to two single breakers like you thought of in your first post is dangerous for several reasons: there is no guarantee both will trip at the same time, and you would have to be sure the two breakers were getting power from different sides of the central bus bar.

All these directions assume that your current breaker box is full. If in fact there is room for more breakers but the knockouts in the front cover have not been broken out, just knock out two and install that 220v 20 amp double breaker. You won't need to replace existing breakers with slimlines if the box has room to take the double. Just take a breaker out and go to Home depot to buy a matching double.GE and Square D both make two kinds of breakers so it's easiest to just take one with you to make sure you get a matching breaker.

Of course, turn off the main breaker while you are running wires through the breaker box. And be careful, because the two big cables coming into the main breakers are STILL LIVE even when the breakers are off.

[rdsk8ter]

It's not too hard to do. Take the front panel off and pull a breaker straight back off the board. Once it's unclipped from the central bus bar and just hanging from it's black wire, it's dead, just loosen the terminal screw to get the wire off. Take the breaker to Home Depot and buy four 15 amp slimline breakers. They will look like skinny versions of what you just took out, and two of them will fit in the same space as a single regular breaker. There are some types/brands of breaker boxes and breakers that will not accept slimline breakers; if you can't find Square D or GE slim breakers that match yours then you are SOL. But most likely you will have no problem. Also buy a twin 220V 20amp breaker, and however much 12 gauge Romex cable you will need, and a box and cover and 220v female receptacle that matches the plugs on your compressor and welder.Also strain reliefs to protect your new cable from the edges of the box you are buying and also where your cable will exit the breaker box. You will need to replace four of the 15 amp breakers in your box with the slimline breakers, leaving a space that the double breaker will fit in. While you have the breakers out of the box, you will see that the central bus bars that the breakers clip to are made so that, as you clip breakers on, they draw power from alternating sides of the central bus bars. These sides of the bus bar carry 110 volts each. Your new 220v double breaker will clip in so that it draws off both of the center bars at once, and will ONLY clip in like this. Connect the black and white wires from your new cable to your new double breaker; pretend the white wire is black and hook it up to one terminal and connect the black to the other terminal.Install the bare copper ground wire from your new cable to the same bar that the other ground wires are connected to. In general, as you work, look at how the electrician installed things and copy it. The only thing you will not copy is that your new white wire will connect to your new double breaker instead of to the bar where the other white wires from the 110 v circuits are connected. Use the strain reliefs just like the electrician did, and staple the cable to the structure just like he did. mount your new receptacle and box wherever you want. You will now have a 220v 20 amp outlet, which will safely run either your compressor or welder, just not both at the same time.

Wiring to two single breakers like you thought of in your first post is dangerous for several reasons: there is no guarantee both will trip at the same time, and you would have to be sure the two breakers were getting power from different sides of the central bus bar.

All these directions assume that your current breaker box is full. If in fact there is room for more breakers but the knockouts in the front cover have not been broken out, just knock out two and install that 220v 20 amp double breaker. You won't need to replace existing breakers with slimlines if the box has room to take the double. Just take a breaker out and go to Home depot to buy a matching double.GE and Square D both make two kinds of breakers so it's easiest to just take one with you to make sure you get a matching breaker.

Of course, turn off the main breaker while you are running wires through the breaker box. And be careful, because the two big cables coming into the main breakers are STILL LIVE even when the breakers are off.

 

 

Wow I dont even know where to start. He needs a 30 amp circiut. The circiut has to be rated as a continuious load 125% of the rated capacity. This puts his 24 amp welder to a 30 amp circiut. The panel is maxed at this point due to the rest of the breakers being GFCI breakers. The walls apear to be finished so the wire will have to be either fished in to a remo box, or put in a conduit due to the lack of experiance on his part its alot easier to do it this way. The flex connector is the insulating bushing in this case. I would say this thread has been resolved at this time

[theghosttanker]

A 210 amp welder puts out 210 amps of low voltage DC welding current. It will draw 15 amps AC at 220 V, so a 20 amp circuit is all he needs.Is the picture posted in your previous post his box?

[Pyro]

you need 220V. That means two 110V lines in different phases.

 

how many plugs do you have in your garage? If you have 2 plugs that are feed by 2 different breakers and they are on different phases, then you can use 2 plugs to power your 220v needs.

 

use a volt meter and test between the hot side of 2 different plugs until you find 220V. The hot side is the smaller slot in the plug.

 

other wise, you need to get into the breaker box.

[rdsk8ter]

according to the nameplate it uses 24 amps Nec requires you to go off the nameplate where applicable I have more infor then just whats on here he gave me the model number I pulled up the info on it and got the nameplate. Because It is capable of running for more then 3 hours it has to be caulculated at 125% and sized to the next overcurrent device witch is 30 amps sorry I forgot he sent the model info to me over a pm just read that. but never the less he needs a 30 amp circiut.

 

 

you need 220V. That means two 110V lines in different phases.

 

how many plugs do you have in your garage? If you have 2 plugs that are feed by 2 different breakers and they are on different phases, then you can use 2 plugs to power your 220v needs.

 

use a volt meter and test between the hot side of 2 different plugs until you find 220V. The hot side is the smaller slot in the plug.

 

other wise, you need to get into the breaker box.

 

 

BAD BAD BAD dont even think about this this is just as bad if not worse then double tapping the breaker.

[Pyro]

Double tapping a breaker is not going to blow you up. either is making a little adaptor cable that uses two plugs. Sure it isn't code, but it gets the job done in a pinch. don't be afraidee cat.

[rdsk8ter]

this from a guy named pyro lol odd isnt it? it wont blow you up but could damage ther wiring in the house. Please dont take this advice if you are reading this

[Brad-ManQ45]

My MM175's panel states it draws 19.1 amps max.

 

When I appl;ied for an electrical permit, I asked for an electrical inspector to come and discuss what I was going to do (a second 120V outlet in the garage and a 220v outlet in the basement and the garage for compressor and welder (not at the same time of course).

 

When the electrical inspector came out he said I had to have a 30 amp circuit for it (that 125% rule) after looking at the welder.

 

30 is definitely what you need...

[woldson]

The main reason for doing this correctly is thermal LOAD of the entire circuit.

This means if you exceed the ablity of the circuit to dissipate heat things will melt and you get a nice fire to keep you warm during the cold months of winter.

There is no getting around this.

Also, the better delivery of maxium voltage to said electical load is SOOOOO much better for the life expendacy of said load!

You almost can not over wire, just under.

If code calls for 14awg go 12awg,,,,etc. The nice thing is you don't ever have to do it again, cause things don't ware out like something mechcanical.

Don't be the smuck on the news.

 

 

Remember as well, breakers just don't throw at rated amprage. Why, initial start up of the load. Start up can easily exceed the amp rating of the breaker.

If conditions are right you can over run the amp capacity of the breaker, and since the wire is rated at that amperage,,,,heat bulid up due to resistance in the wire per the demand, translated FIRE FIRE!!!!

[dr_hunt]

Ok, calm down boys, be civil. Whether it is right or wrong, what the inspector says goes. But in this case he doesn't want an inspector, he wants it to work so he can get by with one receptacle 30 amp off a 220Vbreaker.

[woldson]

One other thing. The longer the run the larger the gauge wire.

Longer equels more resistance, hence more heat, more draw on the circuit to over come the wire to the load.

So something that is five feet away, may have to increase double the gauge wire in a hundred feet, with the same load.

[woldson]

Sorry Dr hunt, just saw your post as I posted.

I'll let it go, just there are other lives at stake and this is really a no brainer.

[rdsk8ter]

One other thing. The longer the run the larger the gauge wire.

Longer equels more resistance, hence more heat, more draw on the circuit to over come the wire to the load.

So something that is five feet away, may have to increase double the gauge wire in a hundred feet, with the same load.

 

there is a long formula for voltage drop you can use or you can just go with the rule of thumn that says for every 100' go up a wire size and youll be golden

[Pyro]

this from a guy named pyro lol odd isnt it? it wont blow you up but could damage ther wiring in the house. Please dont take this advice if you are reading this

 

What? how could you possibly damage the wiring in the house? The worst thing that can happen is the breaker will trip.

 

Jesssss you guys are over thinking this. In most cases, the welder will pull less than 20 amps because full power welding is rarely used.

 

I did electrician work for 4 or 5 years while going to college and did multiple side jobs for the last 15 years and numerous temp power setups (as described above).