220V to 110V converter

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DavidLee

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I have a standard 50 amp 220V socket that I have used just for my miller mig welder. My garage is the typical garage that was built in the 50's that came with just two 15 amp 110V plugs. I would love to have a converter that i can then wire some extra 110V sockets. What would you recommend?
 
I think you could just come off one side of the 220 . 220 is just two 110's on the hot side .
a converter changes AC to DC . A Inverter changes DC to AC .
 
I think you could just come off one side of the 220 . 220 is just two 110's on the hot side .
a converter changes AC to DC . A Inverter changes DC to AC .

Nay verily, I proclaim. If the "220" power in the garage is your typical single phase 240v welder circuit there will be no neutral conductor and thus, no code compliant/safe return path for a 120v load.

I have a standard 50 amp 220V socket that I have used just for my miller mig welder. My garage is the typical garage that was built in the 50's that came with just two 15 amp 110V plugs. I would love to have a converter that i can then wire some extra 110V sockets. What would you recommend?

If you want to break some 120v power off the existing 240v receptacle you would need a small transformer to derive a neutral, which would be cost prohibitive to purchase and install properly. A 240v single phase 50a receptacle will be a NEMA 6-50R and will only have 3 prongs. If this is what you have then chances are there is no neutral conductor. A 50 amp 120/240v single phase receptacle with neutral would be a NEMA 14-50R and will have 4 prongs. Considering most welders use single phase power in either 200/230/460 volts, I'd be really surprised if there was a neutral available at that plug.

Just pay a sparky to run a couple extra 120v circuits to the gayrage. It's your best bet...
 
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Nay verily, I proclaim. If the "220" power in the garage is your typical single phase 240v welder circuit there will be no neutral conductor and thus, no code compliant/safe return path for a 120v load.

If you wanted to break some 120v power off the existing 220v receptacle you would need a small transformer to derive a neutral, which would be cost prohibitive to purchase and install properly.

Just pay a sparky to run a couple extra 120v circuits to the gayrage. It's your best bet..


Thanks that AC current is sketchy stuff
 
what do you plan on running on the extra 120V outlets?
 
OK, let's straighten this out!!!

IF YOU HAVE (like me) an older setup ---I use "dryer plugs" WHICH ARE NOT a neutral!!!! They are TWO wire plus ground, which is the green/ safety ground AND NOT NEUTRAL!!1

Therefore you CAN NOT (legally) use this for 120V (I do anyway LOL)

50-amp-plug.jpg


HOWEVER.........every 240V welder I've seen in the last 40 years had a FOUR WIRE PLUG!! This means it has TWO hot conductors plus the NEUTRAL plus the green/ safety GROUND

Each HOT is 120V to NEUTRAL. This means you have TWO 120V circuits in that plug

N%2014-50R%20125-250-volt.jpg


So IF you have a 4 terminal/ slot/ conductor receptacle, you could wire it for 120 EXCEPT FOR THE following:

You have a HUGE (30-40-50? amp) breaker feeding that circuit, and that is NO PROTECTION AT ALL for 120V outlets.

IF YOU ONLY want something temporary, I would get a small 2- breaker box and put som 15 or 20A breakers in there, and then wire it with a plug to fit the welder receptacle...........go to the box........and then either more cord to something like a couple of receptacles in a box, or mount the box right on the back or bottom of the breaker box.

WHAT YOU HAVE

GROUND/ green is for SAFETY, it hooks directly to the breaker box and the receptacle box, as well as to the green screw on the receptacles

You will need to devise some way of "stepping down" the big wire from the welder plug to fit the breakers. Wire nuts, or careful selection of breakers and your "welder cord" they might fit fine as is

One hot to each breaker, green to the box, and white / neutral gets connected to the white screws on the receptacles, so this will have to be clamped with a terminal/ wire nuts etc and passed on to the receptacles.
 
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So "how" do I get away with using a 3 terminal plug (no neutral) for occasional 120V and WHY would I do that?

FIRST, at my junkhouse, the 240V welder box comes DIRECTLY off the main breaker box. AT THE MAIN BOX the is where main power comes in, and the neutral buss, and the ground buss and the box ground ALL AMOUNT TO THE SAME TERMINAL. This is NOT the case with added breaker boxes / sub panel such as "over at the house." (My main is at the detached garage)

At the house breaker box, which in this case is actually a sub-panel, the box is grounded to a stake, and is grounded to a ground / green conductor coming from the garage. The NEUTRAL at the house box is connected to an INSULATED neutral buss bar, NOT THE CASE at the garage main panel

If you open my box, there is about 2ft total wire "or less" between the box for the welder, the main box, the neutral, and the ground buss. They are one and the SAME

So I have "cheated" and tied the neutral and ground together on my 120V adapter. They are one and the same.

I ONLY do this when I want to use the 120V MIG "far from" the house, as I have a couple of long "welder" extension cables

This is NEVER plugged in for more than long enough to get the job done, certainly not unattended or overnight.

So far as grounding, it is safe because everything that is a "box" is grounded including the welder, which ALSO has a 3 wire plug
 
Get an electrician to look at what you have.

You do not want multiple grounds on your system. Strange things can start happening.
The earth between two grounds can act as a battery.

To be clear this is not a "system." This is a temporary lashup to get 110 (120) at fairly high current "once in awhile.

All US household electrical systems have more than one ground. You sound like you are in Europe? Whole different deal. Here, the 240V neutral is grounded at the pole and at the main box at the house, AKA "meterhead"
 
I beg to differ. The plug in for your welder is part of the system of your home and your garage until it gets out there to that Transformer.

No I'm not in Europe. My father and my brother have worked as lineman and on the Distribution Systems for years. You show me a house with more than one ground I'll show you somebody that's having problems and they may not even know it. There is one main ground and it's usually at your main box the rest of it is grounded through the wiring.
Have an electrician look at your system including your house. It's not worth dying over.

I don't need anybody to look at anything, and you are incorrect, please re-read this thread

1....The OP was looking for a way, I only wrote how I do it. The only thing that is not "code" is the TEMPORARY grounding on the rarely used extension cord

2....There ARE more than one ground on a house system. The house main box ground is the "start" that is the line neutral and the box case ground and the ground stake are all tied together there

When you wire up a sub panel in another building THAT is grounded at that box so IT has a separate ground. That's at least TWO right there

3....If you have a tower IT is grounded by means of multiple ground stakes, and if it has power to it THAT is tied to the tower and therefore tied to the main system ground. That's THREE

4...Plumbing......Gas pipe and plumbing is often bonded to the house system ground and "yes" the gas meter and house water supply both have "dielectric" connectors, but this doesn't mean that an outside faucet might be tied to something else. "Possibly FOUR"

5...Lightning protection.....Some houses have various types of lighting (rod) protection, and THAT is grounded by means of multiple stakes as well as bonded/ tied to the house main ground

SO THAT'S at least FIVE...........separate.......grounds depending on the situation.

Another? ANY metal equipment, such as a welder, or in my case, the outdoor two post hoist. The electrical ground is tied to the metallic box and conduit on the hoist. So the entire hoist is connected to system (green) ground.......traced directly back to the main box.

THE HOIST sits on the GROUND on a metal frame. Isn't that "ground?" I'd think so.
 
I don't need anybody to look at anything, and you are incorrect, please re-read this thread

1....The OP was looking for a way, I only wrote how I do it. The only thing that is not "code" is the TEMPORARY grounding on the rarely used extension cord

2....There ARE more than one ground on a house system. The house main box ground is the "start" that is the line neutral and the box case ground and the ground stake are all tied together there

When you wire up a sub panel in another building THAT is grounded at that box so IT has a separate ground. That's at least TWO right there

3....If you have a tower IT is grounded by means of multiple ground stakes, and if it has power to it THAT is tied to the tower and therefore tied to the main system ground. That's THREE

4...Plumbing......Gas pipe and plumbing is often bonded to the house system ground and "yes" the gas meter and house water supply both have "dielectric" connectors, but this doesn't mean that an outside faucet might be tied to something else. "Possibly FOUR"

5...Lightning protection.....Some houses have various types of lighting (rod) protection, and THAT is grounded by means of multiple stakes as well as bonded/ tied to the house main ground

SO THAT'S at least FIVE...........separate.......grounds depending on the situation.

Another? ANY metal equipment, such as a welder, or in my case, the outdoor two post hoist. The electrical ground is tied to the metallic box and conduit on the hoist. So the entire hoist is connected to system (green) ground.......traced directly back to the main box.

THE HOIST sits on the GROUND on a metal frame. Isn't that "ground?" I'd think so.

I see where you are coming from, but a couple things should be clarified:

The "ground," or equipment grounding conductor, AKA green wire, AKA bare copper wire, is meant to provide a low impedance path back to the transformer in order to clear faults on electrically conductive materials that people may come in contact with. The way it does this is via the neutral tap of the supply transformer, where it will be bonded ONLY at the main panel, as you have pointed out.

Grounding electrodes, AKA ground rods, cold water pipe, etc. are meant only to help keep metal items at ground potential and to dissipate residual fault current into the earth. They are not meant to be the low impedance path needed to open a circuit breaker and eliminate hazardous voltage from metal items that we come in contact with.

The ground at your "sub panel" is tied only to the chassis of the panel at this point because connecting it to the neutral bus would turn every ground wire and bonded piece of equipment/junction box/conduit downstream into a neutral conductor. We call this "objectionable current", and it is dangerous.
 
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i am going to have my panel replaced in a short period of time. I will just ask them to add a few more plugs into the garage. That will give me an excuse to clear the garage and paint the floor at that time.
 
Hmmm, I have a 220 in my basement for dryer that I don't need cause the one I have is gas. I was wondering about breaking the 220 down and run to garage for more juice. Now it's 110 at 15 amps. Sounds as though it is a little more involved than just splitting it in half. I am not versed in electric at all, so this is not for me. Thanks to OP for this thread! And thanks to 67Dart273 also for the info.
 
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