Power requirement for Tig welder question

I'm helping a friend work out the details for a new shop he is building. He has an older 275 amp tig welder, probably a Lincoln, at least 15 - 20 years
old. Power input is the question, it's on 240 volt single phase. The electrician has rough-wired a 40 amp service, which I strongly suspect will not be sufficient. I don't have a specific model to research, but looking at similar size welders I see input current spec'd at about 100 amps, which may not be available - total to the shop is 100 amps. I suggested at least 60 amps and just don't turn up the current past about 150 or so, which won't be a problem - he works with thinner steel (.125" or less), and very little aluminium.
So, can we use a 60 amp circuit for this welder and use discretion on the current dial, or is there a surge requirement in starting the arc, etc, that I'm not aware of? Is 60 amps enough to run a welder like this at 150 amps with about a reasonable duty cycle (my Square Wave 175 is on a 60 amp circuit). What other options are there bar getting a new welder?
Thanks very much, Brian
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

You need a 90 amps circuit. 80 amps at least.
Your buddy's machine pulls about the same as my Syncrowave 250. I run mine on a 90 amp breaker. When I ran it on a 60 amp breaker it would trip the breaker often.
--
"I love deadlines, especially the wooshing sound they make as
they fly by" - Douglas Adams
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

60 will be fine for that size and amperage.
Gunner
"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
i have the lincoln 275 that i usually run off of a 50a breaker. never tripped when welding at 145a tig or stick. some time ago i was tigging al at 200a and it was a no go. in that case i have an extension cord i rigged up using building wire that comes off a 100a breaker in the service entrance panel. works great but looks like hell, i just keep it rolled up behind the bushes. the code allows the wire's amp rating to be doubled if only a welder is on the circuit. the theory is that a welder is not operated long enough for the wire to get hot enough to burn down the building. just be sure the voltage drop is not excessive if you go this route.
Brian wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I would use wire suitable for 90 amps, but put in a 60 amp breaker. My reasoning is........ It is a lot of work to remove and replace the wire, and heavier wire won't cost all that much more. But breakers take a major price jump between 60 amps and anything higher. So if a 60 amp breaker works, then he is ahead. If it doesn't work, it isn't much work to remove and replace the breaker. And the 60 amp breaker is less than $20 if I recall correctly.
I think a 60 amp breaker will work. Lincoln incorporates some power factor correction in their welders. Miller welders come without unless you pay extra for power factor correction. So I think a sixty amp breaker will work, but I would hedge my bet by having wire big enough for 90 amps.
Dan
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It should not be.

Why do you think that 100A service would be a good idea? You still can limit your use of the welder.
My Hobart Cybertig is speced to run at 44 amps THREE phase, maximum.
My phase converter (the old one anyway) uses about 85 amps single phase to supply the current.

A circuit breaker normally is not an instantaneous device under moderate overloads. It could be a few seconds or even more before it trips.
i

--


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 30 Dec 2005 03:52:53 GMT, Ignoramus6309
Chuckle..you must have a smaller drawer than mine. Mine is rated at 102 amps, 3ph. But then..it will do 675 at full throttle.
Gunner
"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Scary stuff! Do you want 3/16" -- very thick -- lanthanated electrodes? Good up to 750 amps? I can sell you some for not too much. AirGas wants $39 for each, I can do $5 each.
i

--


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 30 Dec 2005 05:36:46 GMT, Ignoramus6309

I dont have a torch big enough to run full bore with a big tungsten. Though I did run it with a some 5/16 stick a couple times. I think the arc could be seen from orbit.
Now the welder sits, covered up, unloved, out on a friends ranch, hoping someone will come and get it and give it love and attention. Right next to the Logan 14" lathe, the two fixer upper Boyer Shultz surface grinders..etc etc etc etc
Gunner

"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It should fetch you that $200 on ebay, that you want. Especially with the leads attached. I would expect it to go for $500 or even more.
i
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Fri, 30 Dec 2005 15:00:25 GMT, Ignoramus24987

Shipping would be a killer. I think I, for financial reasons, am going to start up a sellers account this coming month on ebay, and see if I can generate some revenue. Ive too much Stuff..and am pretty good about dragging more home every week..so I guess it makes sense.
Guner
"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.
Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Shipping should not be a big problem if you can deliver to LA or to a freight terminal. You can even list your cybertig as located in LA.
Just one word of warning, as a seller, you have to be relatively organized and do things that you promise to, within promised time, more or less. Like ship stuff within a few days of getting paid, for example.
And also, good feedback == better closing prices.
i
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
By the way Gunner... From a cheapskate...
If I lived close to you, and did not already have a welder, I would gladly pay $200 for your cybertig and would consider it a great deal.
i
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.