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stals
01-06-2007, 02:40 PM
6622

6623

I just purchased a Lincoln Pro Mig 175. My plan is to run a 25' 10 gage extension cord to the dryer outlet. The outlet is different than the plug on the welder. I need some help to make sure I hook it up correctly.

Is the round plug on the welder the same as the L shaped plug on the dryer? I assume this is the ground. The welding plug has one prong larger than the other. Does this mean it requires the positive and negative to be on one or the other? Attached are pictures of the two plugs in question. Any help would be greatly appreciated.

Regards,
Stals

runchman
01-06-2007, 04:02 PM
Yes the ground is the round one as you mentioned and corresponds to the one you said.

with 220 each hot is indistinguishable from the other, so which one goes to which of the flat blades doesn't matter. The one blade is wider just to force it to only fit in the correct kind of outlet.

easiest thing to do is probably to go to home depot, get a plug the same as your dryer has. cut the existing one off the welder and wire on the new one.

or you could make up an extension cord with an outlet on one side to fit the welder, and a plug on the other side to fit the dryer outlet socket.

- John

Oh I just read your post and see you want an extension cord, so forget the cutting off the plug part :)

Rick V
01-07-2007, 11:05 AM
Hi Stals,
John set you straight on the ground pin.

You mentioned your plan to use a 25' 10 gage extension cord to the dryer outlet. I guess it depends upon that extension cord - what it already has on the ends for connectors.

If that extension cord is a typical contractor grade cord for 117 volts AC, I suggest you may want leave that untouched (for all kinds of uses) and make up a couple adapter cables.

#1 - Buy a dryer cable ($15): this gives you the plug that you showed us. Put a good 117 VAC female socket ($6) on the other end.

#2 - Buy a welding female socket (~$10 at Home Dept, totally enclosed wall mount type) ) into which you can plug your welder. Buy a good 117 VAC male plug ($6). Buy a few feet of 10 gauge 3 wire (plus ground) cable. Install the female welding socket on one end of the cable and the male 117 VAC plug on the other.

In use: You plug #1 adapter cable into the drier socket. You plug your extension cord into the 117 VAC female of the #1 adapter. Into the female end of your extension cord, you the plug the male end #2 adapter cord. You plug your welder into the female weld socket on #2 adapter.

Note: As long as the power demand of the welder is 15 amps at 220 Volts, the use of 117 VAC plugs and sockets (usually rated at 15 amps) should be just fine.
e.g. With my Lincoln MIG-PAK 15 (SP-175T), the demand is 15 amps at 220 volts.

The advantage of this approach is that if someone asked you to bring over your welder, you can always add more #10 extension cords if needed. Also, the idea of cutting off the welding plug off the new welder does not appeal to me.

Rick V

runchman
01-07-2007, 01:05 PM
The adapter cables sound like a good idea, just be sure that you dont leave them laying around where someone is going to accidently connect 220 to a 110 device!

Not likely if it is just for you, but you know how people are.....

slamdvw
01-07-2007, 04:20 PM
That new welder plug looks awful big for 115 volt... im thinking its actually a 220 volt plug. Seen one the other day at HomeDepot looked just like it. Was on a 225 amp tombstone, 220v.

Woodshed
01-07-2007, 08:19 PM
When I was in apartment maintenance business we could not change the outlet from 4 to 3 prong or 3 to 4 prongs. Electric code was change out pigtail. If I remember right 3 prong has two hot and one prong was ground and neutral. Under the new code 4 prong has two hot, one ground and one neutral. Changing out the plug on the cord is not safe since ground and netrual are on different plugs. Changing them will still work but lose the safety factor.

runchman
01-07-2007, 09:40 PM
That new welder plug looks awful big for 115 volt... im thinking its actually a 220 volt plug. Seen one the other day at HomeDepot looked just like it. Was on a 225 amp tombstone, 220v.

Yeah, the plug is 220v. The extension cord guy wasnt saying it is 115volt, he was just suggesting using a 115volt extension cord with an adapter cable plugged into both ends, so if need be you could substitute a longer, easy-to-obtain 115volt extension cord.

That way you still have the use of the 115volt cord if need be for a 115volt thing while you arent using the welder.

- John

runchman
01-07-2007, 09:46 PM
When I was in apartment maintenance business we could not change the outlet from 4 to 3 prong or 3 to 4 prongs. Electric code was change out pigtail. If I remember right 3 prong has two hot and one prong was ground and neutral. Under the new code 4 prong has two hot, one ground and one neutral. Changing out the plug on the cord is not safe since ground and netrual are on different plugs. Changing them will still work but lose the safety factor.

For lots of 220 devices though, such as the one in question, there is no neutral - you just have 2 hots and a ground.

So have you decided which approach to take, Mr. Original Poster?

Id say keep it simple, buy three things:
1. Socket that fits your welder plug
2. Plug that fits your dryer outlet
3. Heavy gauge extension cord in required length

cut ends off cord, wire on plugs. Ohm out from one end to the other to make sure the 2 welder blades go to the 2 side blades of the dryer plug.

You should also be able to ohm from the ground of the dryer plug to a point someplace on the body of the welder. (when it is plugged into your extension cord, of course!)

- John

awright
01-07-2007, 10:29 PM
I would strongly discourage making an adapter from 230 volt receptacles to 115 volt receptacles in expectation that you will "be careful" not to inadvertently plug a 115 volt tool into 230 volt power. I speak from experience. Decades ago I did that very thing for a quick expedient. I even put large string tags on the 115 volt receptacle on the end of the extension cord. Worked OK for me for a while, but a guy I hired to help me plugged in one of my best power tools without so much as a glance at the2" x 5" string tag screaming, "CAUTION - 230 VOLTS," on both sides that he had to push out of his way. Destroyed a good Milwaukee drill motor. This guy was even a native english speaker.

Additionally, with a few more decades of experience I've become more cautious and now realize that it is simply foolish and dangerous to set up a booby trap like that with the expectation that there will never be someone, sometime, who plugs a 115 volt tool into the trick 230 volt line.

I don't know for sure, but I would bet it strictly prohibited by the code, and your insurer would not look favorably on it either if something brought them into the situation. And all to save the cost of an extension cord dedicated to 230 volt applications?

Be safe.

awright

GWallace
01-08-2007, 02:17 PM
http://minneapolis.craigslist.org/hsh/254760251.html

Call this guy. Looks like you could make a great extension cord from this.

wojeepster
01-08-2007, 09:25 PM
Crimey, I went to lowes's bought the welder socket and box and wire clamp and got a plug for the dryer and wired up this very extension in 15 min. Something to remember though.... Many welders take 50 amps, many dryers just have 30 amp circuit. The plug you have pictured is 220v 110 one way, 110 the other, round is ground. bent one on dryer is ground. If you are welding on the low side you will be fine if you go over the breakers rating it will blow.

awright
01-09-2007, 03:47 AM
True enough, wojeepster, but the Pro Mig 175 has a rated primary current of 20 amps at 230 volts and rated welding current. While the welder was equipped with a 50 amp connector and the recommended breaker size is "40 amp Super Lag," the 30 amp dryer circuit will probably provide adequate primary current for THAT welder for almost all applications.

Regarding the connectors: I'd like to solicit MAC702's input on this, but my understanding is that the NEMA 10-30 dryer plug/receptacle with the bent prong and the two angled straight prongs is designated for having the bent prong connected to NEUTRAL, not ground. Conversely, the NEMA 5-50 plug with the round prong and the two parallel straight prongs that came on your welder is designated for two hots and a GROUND on the round prong, with no neutral connection since it is not anticipated that this welder will require 115 volt power for any function.

Look at the chart of NEMA connectors at http://quail.com/nema.cfm. The NEMA 10-30 plug/receptacle is described as, "125/250V" and, "3 pole 3 wire," which I think means the angled prong can only be connected to neutral, not ground. In fact, my recollection is that the boxes say something like, "NOT FOR GROUNDING USE." Conversely, the NEMA 6-50 plug/receptacle is described as, "250 volt," and "2 pole 3 wire grounding." In other words, the round prong is a safety GROUNDING connection, not a neutral connection, and you can not legally take 115 volt power from that plug.

Now, I'm not sure of the practical aspects of this, but the poeple on the committees that decide these things have specific safety aspects in mind when they come up with these standards, all having to do with what happens when a fault occurs. My understanding of this (possibly derived from an old post by MAC702) is that in the olden days papal dispensation was granted to allow dryers (and welders) to use the neutral connection as the chassis ground via the neutral prong on NEMA 5-30 dryer plug (or the 50-amp, "125-250 volt," "3 pole 3 wire," NEMA 10-50 range plug with three straight prongs). One motivation was presumably that both dryers and ranges use 115 volts for auxiliary functions like timers and control circuits. I suppose that, as an economy measure, the neutral was previously allowed to be used as chassis ground for dryers and ranges. After all, the neutral is bonded to the ground at the service entrance. Current code requires a four conductor connector for ranges (and, I presume, dryers) to provide the safety chassis ground and the neutral for 115 volt functions.

So, strictly speaking, by adapting your welder to plug into the dryer receptacle I think you are taking a machine that complies with the current code requirements for grounding the chassis and throwing it back to the prior compromise situation (not legal for new products) of using the neutral as the chassis ground.

I'm not being critical of this arrangement. In fact, I used it for a long time. And I don't know if anybody really cares about these things other than electrical inspectors. But I think we should know what we are doing when we make these adaptations and compromises, especially if an inspector could mosey in.

awright

runchman
01-09-2007, 09:54 AM
Look at the chart of NEMA connectors at http://quail.com/nema.cfm. The NEMA 10-30 plug/receptacle is described as, "125/250V" and, "3 pole 3 wire," .....

sheesh are there enough types of nema connectors? Holy cow.

I'd take the outlet off the box and look at the wires. Don't think I'd be content to have neutral connected to my welder box as ground, but that's just me. Sure the neutral and ground are tied at the panel and you'll probably be fine, but still.

I believe the rationale for not using it as ground, is if the neutral/ground connection came apart at the panel, you could now suddenly be the conductivity path from the nuetral on your welder chassis to ground. Zap.

- John

awright
01-09-2007, 01:12 PM
You are correct, John. That's exactly the concern.

In terms of retrofitting, you might find that your electrical box is adequately grounded if it is supplied by wires in EMT (Electrical Metallic Tubing) or armored cable of a certain type. I don't recall the designations, but I believe that older steel armored cable (trade named "BX") was legal for ground, while newer aluminum armored cable is not. Check this out with your electrician or inspector.

If you find that you have red, black, white conductors but no green or bare wire (which you probably won't if they used the old style dryer receptacle) you have no ground unless the electrical box is grounded via conduit or armor. If you DO have an adequate, legal ground, you would be well advised to install a 4-contact dryer receptacle (I don't know what model) with both neutral and ground. Then make an adapter to your existing welder plug using two hots and GROUND. If you did this, you would have to remove the ground strap to neutral in your dryer and install a 4-conductor stinger with the new style plug.

Never forget, I'm not an electrician.

awright

runchman
01-09-2007, 01:42 PM
Never forget, I'm not an electrician.

awright

Maybe not, but you have an inherent understanding of what is actually happening with the current, and that's what counts !

leeschaumberg
01-09-2007, 07:38 PM
People say all kinds of voltages. 110 , 115 , 120 ,125 , 220 , 230 , 240 and 250 volts. A house has only 2 voltages. I call them 120 and 240 volts. If you look how your house panel (you must take off the cover to see) is wired you can see the older 3 wire hookup or the newer 4 wire hookup. If you touch any hot you may die so don't. The only differance between them is the extra negative wire. Now they use earth and ground. Both are negative. Get and use a meter that will tell you. One can cost only less than 10 dollars. You can use it all over. There is many kinds of terminal so use the correct end that you need. Just remember there are 30 and 50 amp terminals. I hope I answered any and all questions without confusing you. Because I don't read this column all the time email me if you have any questions at leeschaumberg@hotmail.com .:)

billie_
01-09-2007, 08:47 PM
if your dryer was a 30 amp breaker adn wired by a real electrican..then your wire size will also be correct for the 30 amp breaker...if you use this set up with a home made extension cord and your welder needs a 40 amp breaker but you use the 30 amp..you will likely blow the breaker often....and if you then replae the fuse with the one recomended for the welder you will be overloading the wire and have a chance for a fire ... i read in an earlier post "the 30 amp dryer circuit will PROBABLY provide adequate primary current for THAT welder for ALLMOST all applications."

those are risky words when talking electricity

Pentawelder
01-09-2007, 10:46 PM
"The only differance between them is the extra negative wire."
There are no negative or positive wires in an AC circuit! The
wires are called hot, live, L1, L2, neutral, return, ground among many others
but NEVER positive and negative (unless you have DC power to your house or business).

Sandy
01-10-2007, 12:03 AM
I'm not being critical of this arrangement. In fact, I used it for a long time. And I don't know if anybody really cares about these things other than electrical inspectors. But I think we should know what we are doing when we make these adaptations and compromises, especially if an inspector could mosey in.

Nicely put. It isn't really feasible to retrofit a home every time technology or code changes or a new device is purchsed. If a person, as you say, has an understanding of current and past codes and arrangements then I believe we can hook up any modern device to an older home and have as safe an installation as when the home was originally built. Just becuse the newest codes are more safe doesn't mean the old codes were unsafe.

In all reality there should be more safety concerns with having a dryer plugged into a three wire receptacle than a welder. :)

leeschaumberg
01-10-2007, 07:21 AM
"The only differance between them is the extra negative wire."
There are no negative or positive wires in an AC circuit! The
wires are called hot, live, L1, L2, neutral, return, ground among many others
but NEVER positive and negative (unless you have DC power to your house or business).

Notice the writer says first - The only differance between them is the extra negative wire!
Then the writer says there is no negative wire! Hmmmmm
L1 equals line one. This is one side or half of the total voltage available. 120 volts.
L2 equals line two. This is also half of the total voltage available.
120 time 2 equals 240 volts!
L1 and L2 have the workable current that is used by the devices to run.
The current exits L1 and L2 goes to the device then exits and goes to a return path to complete the circuit. The return is called the return path and called the negative or (there is no negative).
In the wall panel there is two legs in the center which are wired to L1 and L2. On the side is the return path. Here this path goes to a rod (10 foot copper rod driven in the ground). The nonexistant negative or ground wire.
The new code says put 2 of them in in case one doesn't work or in case the ground (earth) is too dry. Kinda like the regular 120 volt outlets that have 2 grounds. The narrow terminal is the hot(120 v) and the wide is the ground or nonexistant negative. (Confused yet):laugh:

Clay Walters
01-10-2007, 10:06 AM
Lee,

The writer's first line is in quotes. He is correcting someone else.

Regards,

Clay

runchman
01-10-2007, 11:10 AM
The current exits L1 and L2 goes to the device then exits and goes to a return path to complete the circuit. The return is called the return path and called the negative or (there is no negative).

Well not exactly; for a 120 circuit, the path is L1-Neutral or L2-Neutral. For a 240 circuit the path is L1-L2. Since it is AC the current goes both ways, L1 to L2 for half the sine wave and L2 to L1 for the other half. Same thing with a 120 circuit and the hot-neutral pair of wires.




Kinda like the regular 120 volt outlets that have 2 grounds. The narrow terminal is the hot(120 v) and the wide is the ground or nonexistant negative. (Confused yet):laugh:

Even though the neutral and ground ARE tied together at the panel, it isn't really like the outlet has '2 grounds'. One of them (the round plug, the real ground) is truly tied to ground, and has NO connection with the neutral. This is the safety ground; should something go haywire inside the device and 120 contacts the chassis, the short to ground through this safety ground pin will trip the breaker and save you from getting zapped.

The neutral terminal IS a current carrying conductor and should not be confused with the safety ground.

These discussions make one realize why an electrician can be money well spent, eh??

- John

Woodshed
01-10-2007, 11:54 PM
Also if you do something your self and don't have license electrican do the work and a fire starts and burn down your shop and insurance company find out the work wasn't done by license electrican can cancel your insurance and not pay for any damages.

GWallace
01-11-2007, 10:08 AM
Bingo.

seamus
01-11-2007, 07:15 PM
Stals,

I just went down to the local electrical shop. I bought the male connector for the dryer outlet hookup, a couple of feet of 10/3 cable and the female connector for the welder.

I followed the instructions the guy at the counter gave me:

"Green to ground, black and white to hot."

30 minutes of work and $25. The only tools used were a flat head screwdriver, a wire stripper capable of stripping 10 gauge wire and a razor blade (to strip the cable's outer surface and access the individual wires). And I'm not an electrician. I actually picked out what connectors I needed from a big picture poster of plugs.

If you're not comfortable doing it, just tell the electrician at the shop and they should be able to do it for you right there.

awright
01-11-2007, 08:58 PM
Excellent! Next thing you know you'll be rewiring the house.

I have only one comment: Any time you connect a white wire to "HOT," it MUST be identified as such so someone does not assume it is a neutral. You do this by coloring the insulation at both ends for an inch or more with a permanent pen (a "Sharpie" works well) or by wrapping electrical tape around the insulation for an inch or so at each end. Black or red is commonly used. I don't know what other colors are permissible, but green is definitely NOT permitted as it always designates earth ground.

Enjoy your new welding capability.

awright

acelatrace
01-12-2007, 03:21 AM
I am an Electrician and a Welder. Confused? At one job I try to prevent short circuits, and at the other I create short cicuits. Lol. This welder hookup has no problems provided that the round prong of the welder cable is connected to the ground connection in the dryer socket. The neutral (or white) wire is not required by the welder. It is required by the dryer because of it's need for 120v for some of its components. The neutral is not a negative as one fellow stated but is the return current carrying conductor. In a three phase system it carries the unbalanced load and therefore can be carrying a large current. Without getting into a complex discusion, let's just say that it cannot be confused with the ground conductor. The ground is there for safety, and in the case of the welder is connected to the case so that any stray hot wires comming in contact with the case will trip the breaker or blow the fuse, whichever is used. House wiring does bond the neutral with the ground as it is a single phase system. Using the white wire in an extension cord does not pose a problem as it is impossible to confuse 120 volt plugs with 220 volt, although it is not a bad idea to wrap some black or red tape @ each end for un-knowing do it yourselfers. The 30 amp breaker is there to protect the conductors, and as such the cord must be min. #10 AWG to carry the allowed current, even though the welder may only use 20 amp. Smaller wire will burn up before tripping the breaker and be a fire hazard. I hope some of this makes sense, and happy welding.

ACE

MoonRise
01-12-2007, 12:07 PM
Just to add to the information mix here.

Hi Ace, here in the US the NEC has some allowable wire sizing exemptions for welding circuits because of the duty cycles typically involved.

I don't have a copy of the NEC handy, and haven't memorized the allowable wire-sizing exemptions for welders (haven't had a need to memorize -that- info), but it is an appreciable size difference allowed on branch circuits for welding.

There is certainly nothing wrong with doing the circuit in accordance with the 'regular' wire sizing requirements, but a circuit used for a welder may have the wire size be smaller than 'regular'.

In general, the breaker or fuse is sized for the equipment's needs and then the wire size is chosen to match the needed current capacity of the breaker. We'll ignore temperature derating, the 80% capacity rule, conduit/raceway fill allowances, voltage-drop over distance, and welding circuit exemptions for now. In general, the breaker is there to keep the wire from melting or overheating.

Just like Ace (and others) have said, the breaker is there to primarily protect the conductors from overcurrent.

If you don't -know- what you are doing or are uncomfortable doing the operation even if you know what you are doing, find someone who KNOWS what to do.

And I'll repeat what awright mentioned. If you use a white wire for anything other than 'neutral', then you are supposed to mark it in some manner (electrical tape, permanent marker, etc) to denote that.

Oh, and to stals the original poster, your welder's manual recommends/requires that the electrical service for the welder is #8 AWG conductors and a 40A super-lag breaker/fuse and the ground wire can be #10 AWG (page A-6 of the manual). Using the machine on the 30A #10 AWG dryer circuit will work OK for most settings on the welder except the higher/highest ones, which will most likely trip the breaker. The machine is rated at 230V-20A input and 130A output at a 30% duty-cycle, but the machine can output a max of 175A. Which means that the machine will be pulling at least 27 amps at max output, most likely popping the 30A breaker when you pull the trigger especially if the input voltage is running a little less than a full 230V.