Need help picking the right mig welder

[sberry]

The neutral cannot safely nor legally be used as the ground.

Its used all the time in a 3 wire bonded appliance. If the 3rd is a current carrying conductor and should it become interrupted there is voltage potential on the appliance side of the wire and in the true nature off resitance in wiring although the N is a grounded conductor its not truly isolated due to the fact it has current,,,, insulating this current from the frame and adding a 4th keeps it and everything the same potential as N at service main as well as the ground you are standing on and any other grounded metal in the same system. ????? Clear as mud????

 

[sberry]

My new construction build garage condo has 3 prong 220volt plugs that were wired for welders I have my 5hp compressor in one snd my 200 amp mig in the other.

Not saying it's right but it works.

These are correct. There are 2 ungrounded current carrying conductors which operate the appliance at 240V and one grounding conductor which terminates at service main neutral, it may be thru a 4th wire if on a sub.
When an old 3 wire recept is used to feed a 3 wire bonded appliance it then violates the intention that a new 4 wire provides which is an insulated neutral (lots of focus on th ground but its only part of it) when it is connected to a welder or an air comp it is as grounded as any other circuit with the only exception being the yoke of the recept.

 

[sberry]

Even though you've already purchased I'm going another vote for the Lincoln 180. Stepless adjustment knobs let you dial right in on your settings. I'd been using a mates one for about 6 months until recently when I took advantage of a "what do you want for Father's Day?" enquiry to go buy my own.

I actually like the stepped version or taps as good or better than the variable V from a user perspective. They however have been making it along time and the Linc is very good and tuned flawless with 030 solid. It was right on the button when they invented,,, or designed it and they didn't fiddle along the way.
I don't have seat time with the new Millers, by reliable accounts they are good. The Hobarts are good, I have ,more experience on a couple older models where they were adding gears from a lame 4 speed to 7's which are pretty good and the 210's a pinch more poop on the top than the red 180 but till you get there the arc on the red is as good maybe even better but this is a pretty fine line and really irrelevant to all but the test crowd..

 

[sberry]

Despite this sounding like a ramble which is is,,, we can see where some circuits even go so far as to require an insulated ground wire. In the case of the orange ones found in hospitals the yoke of the recept is insulated from the ground pin.
They want this insulated from everything especially water pipes and other circuits and even from the pipe itself with both the ungrounded conductors and the grounded conductor.
As I recall there is this in hot tub and pools. No way should this be jack legged and interrupted from a pathway to neutral service main.

 

[sberry]

(B) With Circuit Conductors. By an equipment grounding conductor contained within the same raceway, cable, or otherwise run with the circuit conductors.
NEC HANDBOOK COMMENTARY;
One of the functions of an equipment grounding conductor is to provide a low-impedance ground-fault path between a ground fault and the electrical source. This path allows the overcurrent protective device to actuate, interrupting the current. To keep the impedance at a minimum, it is necessary to run the equipment grounding conductor within the same raceway or cable as the circuit conductor(s). This practice allows the magnetic field developed by the circuit conductor and the equipment grounding conductor to cancel, reducing their impedance.
Magnetic flux strength is inversely proportional to the square of the distance between the two conductors. By placing an equipment grounding conductor away from the conductor delivering the fault current, the magnetic flux cancellation decreases. This increases the impedance of the fault path and delays operation of the protective device.

 

[woodturner9]

I don't get all this debate regarding ground and neutral. Inside a main panel the ground and neutral are bonded, making them the same potential electrically.

That is exactly the point - the neutral and the ground are NOT the same electrically.

This is a common misunderstanding, because most people don't have experience with fault events. When a fault occurs, the bond in the service panel looks like a high impedance path at the receptacle if there is not a separate ground wire - so the person gets electrocuted and killed, because they look like a better ground (lower impedance) than the neutral.

I can go though the technical explanation and math if anyone wants, or you can just ask an experienced electrician.

 

[woodturner9]

My new construction build garage condo has 3 prong 220volt plugs that were wired for welders I have my 5hp compressor in one snd my 200 amp mig in the other.

Not saying it's right but it works.

That is probably correct, two hots and ground wire. It's the dryer receptacle that is an issue, because a three prong dryer receptacle does not have a ground wire.

 

[woodturner9]

Its used all the time in a 3 wire bonded appliance.

I disagree, the neutral is never legally used as a ground in current NEC. Could be a grandfathered exception, but normal practice is not to bond the appliance to the neutral.

 

[sberry]

You are correct that this is now not a legal installation, I am trying to explain how it operates and this wire knows absolutely no difference which recept it goes thru. Adapters to these circuits are used all the time and they are safe.
The wire in either outlet goes to service neutral main on a main panel. There is only one difference in it, the 6-50 has a bond pin.

 

[sberry]

I disagree, the neutral is never legally used as a ground in current NEC. Could be a grandfathered exception, but normal practice is not to bond the appliance to the neutral.

It is grandfathered under some conditions but,,,,,,,,,,,,,,,, one of the reasons I even bother here is I suspect you are in the middle of studying this and while we got some real code quoters here they are not all bent on teaching. In the end you are going to land the wire correctly so its not so much an issue but I wouldnt mind it being clear you completely understand what you are doing and I am not sure that is the case here.
I sympathize, I have been there, it takes a while before it becomes a reaction to think of it in the way it operates, then the code makes sense.

 

[sberry]

Take off an old range plug, install a welder plug, only code difference is the color of the wire.
It isn't even a neutral until you actually plug something in, until then its a grounded conductor.

 

[2mJps]

I have a HTP that i bought new in 1988. Its made in the USA and one of the best things i ever bought. I think its a 120. I use stick on heavyer metal. I want to get a 200 HTP some time. It is used alot more than just a hobby welder and by alot of diffrent guys over the years i cant think of any thing bad to say about it.

 

[sberry]

I can go though the technical explanation and math if anyone wants, or you can just ask an experienced electrician.

Feel free, elaborate away.

 

[woodturner9]

I suspect you are in the middle of studying this

actually I teach it.

I wouldnt mind it being clear you completely understand what you are doing

I'm concerned you aren't clear, since you keep saying that neutral and ground are electrically the same, which they are NOT. It is a common misunderstanding, just trying to clarify it so others don't hurt themselves.

Simple way to prove they are not the same, and that ground does not work like a regular AC circuit: Stick one lead from a DVM into the earth, connect the other lead to a ground terminal on a receptacle, measure resistance. What do you read? By your view, you should read close to zero ohms, but you will actually read high resistance. The reason is that the connection is a low impedance connection, but is mostly reactive (imaginary part of impedance) rather than resistive (real part of the impedance).

 

[woodturner9]

Feel free, elaborate away.

If you want the detailed explanation, let's move the discussion to the electrical forum. I'm happy to help you understand and to explain it, but that seems a better forum for it.

 

[woodturner9]

Take off an old range plug, install a welder plug, only code difference is the color of the wire.

A range receptacle is wired differently from a dryer receptacle - the range is a 220 VAC appliance, the dryer also needs 110 VAC. A range receptacle could be used for a welder, since it has two hots and a ground like any other 220 VAC receptacle. It's the 3 prong dryer receptacle that cannot be safely or legally used for a 220 VAC appliance or welder.

 

[sberry]

How long you been doing this? I used the old range as an example and it is wired exactly as an old dryer.

It's the 3 prong dryer receptacle that cannot be safely or legally used for a 220 VAC appliance or welder

. No one is saying it is a legal recept for the welder but it wont know the difference. Both wires are terminated on the same bbar in the panel no matter which recept is used, 3 wire or 4 wire.
The only unsafe thing about using a old dryer or range plug is basically the fact if you mounted one in a metal box it wouldn't be grounded, neither is the backing plate or the yoke in a surface mount. Install it in a box with grounded pipe and its safe for the welder. No,,,,, its not a listed application but it doesn't change the priniciple.

 

[trackwelder]

This electrical **** gives me a headache. I'm glad to have friends to do my electrical work.

 

[woodturner9]

No one is saying it is a legal recept for the welder but it wont know the difference.

That's the point you are missing - it is NOT the same, and the welder WILL "know the difference" when a fault occurs.

 

[sberry]

No it wont. You are right, take this over to the electric forum, there are a couple guys there probably be more than happy to splain it better than I can. But, where would one be teaching at? I am going to say high school shop.
I do have have a question then. Where is a fault returned to?

 

[sberry]

Simple as this. Where in the panel do you land the N wire from a dryer and where do you land the ground wire from a welder? Many main panels do not even have an auxiliary ground bar. The only reason to use it is for crowd control.
A fault is back via wire to the transformer that brung it. Most are 120V, ground wire delivers short circuits to the N bar. We had one the other day that sat on a grounded gfci bench and was 2 wire battery charger. The worn cord was hidden but it shorted to the grounded conductor (white wire) and never tripped the gfci.
And to be clear no one here is talking about bootlegging the ground pin on a 120v 3 wire.

 

[sberry]

The fault is only part of the story. The main reason for 4 wire over 3 is so we can insulate all the current carrying conductors. None would flow over metal gas line from building to building or between equipment, with the advent of phones and old modems all have the potential a well as a little bit of earth for carrying current. No more neutral currents on machine chassis. There is some voltage on a N wire due to the fact current is flowing on it but its termination on the system is at the same point.
The ground wire puts it all at the same and provides for a fault return should the N wire become interupted, it cant leave a standing potential on the machine. I have seen it with home brewed switches and a couple other times, didn't have amachine electrically grounded and had 120 on it, the ground it sitting on never allowed for more than 20A or enuf to trip a breaker.

 

[woodturner9]

No it wont.

Sorry, that's just wrong.

But, where would one be teaching at?

Electrical engineering at a tier 1 research school.

Where is a fault returned to?

Earth ground, which is NOT the same as neutral.

I think your basic misunderstanding is that you are trying to think about AC circuits as if they were DC circuits - which is not correct.

I'll see you on the electrical forum.

 

[woodturner9]

Simple as this. Where in the panel do you land the N wire from a dryer and where do you land the ground wire from a welder?

Again, you are misunderstanding the difference between DC and AC circuits.

A fault is back via wire to the transformer that brung it. Most are 120V, ground wire delivers short circuits to the N bar.

No, that is the point - the fault wants to return to earth ground, and without the AC ground wire, a person may look like a better path - so the current flows through the person rather than the wire.

 

[woodturner9]

The main reason for 4 wire over 3 is so we can insulate all the current carrying conductors.

Sorry, no. All current carrying conductors in a 3 prong receptacle (e.g. two hots and the neutral) are insulated. The reason the 4 prong is now code required is the fault protection provided by EGC.