i'm almost afraid to ask, since any topic i get into that involves welding current and/or safety always seems to draw too many opinions and not enough fact. but here goes anyways: does anyone here own and/or use a miller econotig? i'm specifically interested in what the specifics are for the branch circuit you run it on. i was looking at the manual for one and it has a couple of input current / fault protection requirements that mildly surprise me. if you have access to one, could you please tell me what you use for a breaker size and awg for both the hot leads and the ground wire. i posted this question on a different forum, but nobody has responded yet. i figured i'd check here in case anyone here actually had one.
anyone here own an econotig?
- Thread starter lostcause
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Wyatts dad
New member
Guess if you had no reply since march it is already done, if not, check the owners manual, if you dont have one, Millerwelds will download it for free, there should be a suggestion in there, there was for my Miller sycowave. My machine has the amps on the back of the machine and a good electrician can suggest a good wiring setup. FYI, make sure you install a very good ground rod close to the work area and one dedicated to the branch panel. The high freak can back feed searching for ground and blow your board, about $800 part minimum. also keep your cables in good shape for the same reason especially if you mount a thumb control or have built in thumb control, another source for backfeed to destroy the board.
/facepalm
don't get me wrong, i appreciate the effort to reply, but this is kind of what i was alluding to in the original post.
i posted this a few hours ago. maybe you saw my registration date of march and got them mixed up?
as far getting a manual... in my post i said i'm looking at the manual and that's where the confusion comes from. i'm just trying to see if anyone else has one and whether they know the specifics of the circuit that they run it from. i didn't want to go into all the details right now, but i guess i'll have to in order to fend off a few of the tangents form the start...
i could be wrong, but when you buy #6 nm copper cable i believe it generally comes with a #10 ground wire doesn't it? for those who have this machine, did they run another larger (#8) wire for a ground or did they just plug it in and not notice that the size of the ground wasn't up to specs?
Bill_C
Gold Member
Well according to the brochure here http://www.millerwelds.com/pdf/spec_sheets/AD1-2.pdf it needs 52 amps for full power on a 230 volt circuit.
So you need a breaker bigger than 52 amps. The next size up is 60 amps. So you get a 230 volt breaker, rated 60 amps. (Note: when folks say 220 or 230 or 240 volts, its realistically the same here in the US, that's nominal voltage)
You could put it on a 50 amp circuit breaker, or a 40, or a 30...but if you try to run at full rated welding power, the breaker would trip.
Now that you've sized the breaker at 60 amps, you need to size the wire. The insulation class and how the wire is run (in a conduit or raceway) will determine the minimum gage needed to meet the ampacity. #6 NM is rated for 55 amps, but the Code would (in the past, I think it still does) let it be used with the next available size breaker (60 amps). Also the Code has a provision for welding applications for duty cycle, so in that case #6 would likely be sufficient.
If your cable run is very long, however, you will also have to factor in voltage drop. Say you're running a couple hundred feet from the breaker out to an outbuilding. The wire has an internal resistance, which means the voltage at the end will be less than the voltage at the breaker. If this voltage drop is excessive, you must go to a heavier wire. There are Java script calculators floating around the Internet which can do these calculations for you, enter the current and distance and wire size, they calculate the voltage drop.
Let's say the #6 winds up being OK. You have two #6 conductors and the smaller ground. The two conductors are wired directly to the breaker. The smaller ground goes to the ground buss. The ground normally does not carry much if any current, that's why it can be smaller. The predominant share of the current is carried by the two conductors that are tied to the breaker--this is a 220 (230, or 240, whatever you chose to call it) breaker.
If you aren't sure about this, don't feel like anybody's picking on you, but if it doesn't make sense, I would advise that you call an electrician.
So you need a breaker bigger than 52 amps. The next size up is 60 amps. So you get a 230 volt breaker, rated 60 amps. (Note: when folks say 220 or 230 or 240 volts, its realistically the same here in the US, that's nominal voltage)
You could put it on a 50 amp circuit breaker, or a 40, or a 30...but if you try to run at full rated welding power, the breaker would trip.
Now that you've sized the breaker at 60 amps, you need to size the wire. The insulation class and how the wire is run (in a conduit or raceway) will determine the minimum gage needed to meet the ampacity. #6 NM is rated for 55 amps, but the Code would (in the past, I think it still does) let it be used with the next available size breaker (60 amps). Also the Code has a provision for welding applications for duty cycle, so in that case #6 would likely be sufficient.
If your cable run is very long, however, you will also have to factor in voltage drop. Say you're running a couple hundred feet from the breaker out to an outbuilding. The wire has an internal resistance, which means the voltage at the end will be less than the voltage at the breaker. If this voltage drop is excessive, you must go to a heavier wire. There are Java script calculators floating around the Internet which can do these calculations for you, enter the current and distance and wire size, they calculate the voltage drop.
Let's say the #6 winds up being OK. You have two #6 conductors and the smaller ground. The two conductors are wired directly to the breaker. The smaller ground goes to the ground buss. The ground normally does not carry much if any current, that's why it can be smaller. The predominant share of the current is carried by the two conductors that are tied to the breaker--this is a 220 (230, or 240, whatever you chose to call it) breaker.
If you aren't sure about this, don't feel like anybody's picking on you, but if it doesn't make sense, I would advise that you call an electrician.
Wyatts dad
New member
I bought a used machine that did not work thinking how bad it could be? Turns out the previous owner did not use it much and based upon the repairs did not have a good wiring setup. The board and a few other things were shot. Learned a lot in the process, we did as noted above, put in a 60amp breaker, the tag on back said 54mp. My Miller owners manual suggest (on page labeled electrical service guuide) a 60amp fuse (time delay) 80 amp (standard). Since I am only doing light gauge stuff, we stayed with the 60 amp breaker. We made up a very heavy copper extention 25 feet long#6 so I could move freely about the garage. We also put in a wall receptacle, they are a weak spot, none of the heavy plugs at the supply house were rated for 60, the highest with ground was only 50, upon further inspection, the insides of the 50 were just as heavy as a 60 without a ground.
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thanks for the replies. as far as my understanding of the wiring process, i think i'm in pretty good shape.
last year i ran underground service from my house to my garage. i put a 100a panel in the shop and even had to bump the wiring up due to the long run (about 175ft) in order to still have the entire 100a capacity at the sub panel. the sub panel is connected to the main panel with 4 wires - 2 hot, 1 neutral, 1 ground. additionally, the sub panel is grounded with a separate wire and two rods, and the neutral and ground are not bonded.
i wired three separate circuits for 120v receptacles, and i also ran separate 6/3, 8/3, and 10/3 circuits for current and future machinery. i use breakers sized suitably for whatever device i need. currently the 10/3 w/15a breaker for a compressor, the 6/3 w/50a breaker for welders, and the 8/3 currently has a 20a breaker and the only thing i plug into it is my lathe. note that each of the 240v circuits was wired with x/3 nm cable. i did that in case i ever need to power a 120v/240v appliance. currently the unused neutrals are wire nutted, taped and stuffed in the back of the gang box.
i asked not so much for advice on what i should do, but in trying to find what others actually have done. this is due to what i see as anomalies in what miller lists for requirements as follows:
1. miller states that their specifications for powering the 230v single phase is rated for 100% duty cycle (though this is physically impossible). they call for #6 hot wires with a 60a breaker. i'm not up on all the specs, but i was thinking that #6 was good for 50a, or maybe 55a. is it capable of more in all applications? i know there are specific welder duty cycle clauses where you can undersize the wires because they cannot carry current long enough to overheat with low duty cycles. those cases require special labeling and nothing is mentioned of that. since the manual states 100% duty cycle can you use a 60a breaker with 6/2 or 6/3 nm at 100%?
2. they say to use #6 hot leads and a #8 ground. when most people (homeowners / handymen - not welding professionals) wire (or hire someone to wire) a circuit for a welder, it is often done with 6/2 nm and a 50a breaker. this will run the most common stick welders and wire feed welders that end up in home shops. unless i am mistaken 6/2 (and 6/3) generally has a #10 ground, but the miller manual calls for a #8. are people running specially sized grounds or unknowingly just using the #10 that is in the 6/2 or 6/3 nm cable?
3. the econotig has a standard 50a plug. can you use this with a 60a 100% duty cycle circuit? also, as was stated above, all the receptacles for these plugs are also rated for 50a. same issue.
last year i ran underground service from my house to my garage. i put a 100a panel in the shop and even had to bump the wiring up due to the long run (about 175ft) in order to still have the entire 100a capacity at the sub panel. the sub panel is connected to the main panel with 4 wires - 2 hot, 1 neutral, 1 ground. additionally, the sub panel is grounded with a separate wire and two rods, and the neutral and ground are not bonded.
i wired three separate circuits for 120v receptacles, and i also ran separate 6/3, 8/3, and 10/3 circuits for current and future machinery. i use breakers sized suitably for whatever device i need. currently the 10/3 w/15a breaker for a compressor, the 6/3 w/50a breaker for welders, and the 8/3 currently has a 20a breaker and the only thing i plug into it is my lathe. note that each of the 240v circuits was wired with x/3 nm cable. i did that in case i ever need to power a 120v/240v appliance. currently the unused neutrals are wire nutted, taped and stuffed in the back of the gang box.
i asked not so much for advice on what i should do, but in trying to find what others actually have done. this is due to what i see as anomalies in what miller lists for requirements as follows:
1. miller states that their specifications for powering the 230v single phase is rated for 100% duty cycle (though this is physically impossible). they call for #6 hot wires with a 60a breaker. i'm not up on all the specs, but i was thinking that #6 was good for 50a, or maybe 55a. is it capable of more in all applications? i know there are specific welder duty cycle clauses where you can undersize the wires because they cannot carry current long enough to overheat with low duty cycles. those cases require special labeling and nothing is mentioned of that. since the manual states 100% duty cycle can you use a 60a breaker with 6/2 or 6/3 nm at 100%?
2. they say to use #6 hot leads and a #8 ground. when most people (homeowners / handymen - not welding professionals) wire (or hire someone to wire) a circuit for a welder, it is often done with 6/2 nm and a 50a breaker. this will run the most common stick welders and wire feed welders that end up in home shops. unless i am mistaken 6/2 (and 6/3) generally has a #10 ground, but the miller manual calls for a #8. are people running specially sized grounds or unknowingly just using the #10 that is in the 6/2 or 6/3 nm cable?
3. the econotig has a standard 50a plug. can you use this with a 60a 100% duty cycle circuit? also, as was stated above, all the receptacles for these plugs are also rated for 50a. same issue.
accordionman
Gold Member
HELLO,
yes, i have owned one for several years. i have it
wired with # 6 wire, and a 50amp breaker. in my
opinion it is a fine welder. a lot of people bad mouth
this machine. it is not a high amp machine, but it will
do small, and delicate work, and that is why i have one.
it will also do stick welding.
good luck to all.
accordionman
wlbrown
wright city, mo.
yes, i have owned one for several years. i have it
wired with # 6 wire, and a 50amp breaker. in my
opinion it is a fine welder. a lot of people bad mouth
this machine. it is not a high amp machine, but it will
do small, and delicate work, and that is why i have one.
it will also do stick welding.
good luck to all.
accordionman
wlbrown
wright city, mo.
don't suppose you know for certain what size the ground wire is?
accordionman
Gold Member
SIR,
it appears to be a #10 ground wire.
i have had no probems with this
machine. one time i had problems with
the argon flow. the machine is mounted
low on a shelf, and the top is a steel plate,
and it has casters on the cart. i had pushed the
cart against something, and it pinched the
hose that supplies argon. after i found out what
had caused it, i moved the cart out a bit, and
this solved the gas flow problem.
good luck with your projects.
accordionman
wlbrown
wrigtht city, mo.
it appears to be a #10 ground wire.
i have had no probems with this
machine. one time i had problems with
the argon flow. the machine is mounted
low on a shelf, and the top is a steel plate,
and it has casters on the cart. i had pushed the
cart against something, and it pinched the
hose that supplies argon. after i found out what
had caused it, i moved the cart out a bit, and
this solved the gas flow problem.
good luck with your projects.
accordionman
wlbrown
wrigtht city, mo.
RPW
Veteran Member
- Joined
- Aug 12, 2009
- Messages
- 1,105
When I had an electrical panel put in the shop specifically for welding I had them run a 100amp circuit to the panel and then I use a 50amp breaker for the econotig. As this was in my home in the city I didn't want to have any issues with fire marshal etc. As far as the econotig I use it as much as possible, love the machine. Lately I've used it more for arc welding than tig but it's very easy to use on tig. Lots of control.
Good luck.
Good luck.
