350-400amp single phase

[brightspark]

Agricultural

lol i was working on a farm and there transformer had blew up was fed of an 11kv line and 80 years old . it had never been checked and had coroded and lost some oil. then it went pop goodstyle

 

[PTvor]

it must have been an old p....ss poor transformer and feed. the boards cutout fuses generaly match the size of the supply cable so the cable cant be overloaded

I can think of a few places in country areas where you have a transformer on a couple of poles, which looks like it's been there since the fifties, which serves three or four houses. Sometimes there's a long cable run to the furthest house. This was all installed before the days of 9KW electric showers.

What's supposed to happen and what comes about over the years and no one bothers to check because it all works, are different things.

 

[brightspark]

even in the towns substation maintenance isnt getting carried out as they havent the manpower to do it .there 2 busy doing emergency repairs instead and lack of staff since privatised

 

[Kent]

A tip if anyone who wants to sell you something says something won't do the task you require Listen carefully
carefully

 

[wheresmejumper]

I think some people are confusing what welder you can run on a single phase supply,with what you could run in a house with sockets cooker etc on at the same time.
Which wasn't the original question.

 

[dan.taylor.1]

I'm failing to see why if you have 63a available with other stuff running (my poxy little farm workshop has 100a to it!) That you can't run a big mig that is over 250a. My supply is quite happy with the 3hp compressor going and the plasma and me migging without a tripped fuse in sight, that's max draw 78a if they're all on full chat.

 

[brightspark]

I'm failing to see why if you have 63a available with other stuff running (my poxy little farm workshop has 100a to it!) That you can't run a big mig that is over 250a. My supply is quite happy with the 3hp compressor going and the plasma and me migging without a tripped fuse in sight, that's max draw 78a if they're all on full chat.

and even without allowing for diversity u still have 20 amp more capacity

 

[Kent]

The idea of the fuse is not to overwork the cable etc.fuse the supply too high is kinda dumb! I have 100 amp to mine and an 80 amp fuse. Go get your 400 amp welder and run some measured 350amp runs off the single phase mains. This is something I was asking myself a few months back, found the answers and learned some things along the way, still looking for a big single phase MMA inverter 250 amp tec arc is the biggest I can find that a company will allow me to prove, saw Jims post on the lash up which got me thinking of other ways to skin cats though

 

[dan.taylor.1]

Cables rated to more than 100a (16mmsq swa so 140aish) fuse is 100a main incommer and each 32a is on its own c type mcb. I can see if say the plate with max current input is telling porkies and it pulls more, but if it's saying at 32a in it'll put out 300a then where's the issue.

I appreciate most plates aren't worth the plastic they're printed on but even so if it says 40a and it actually pulls 50, it'll be on a 63a plug/breaker anyway so again no issue.

 

[dan.taylor.1]

Also transformer at ours is big enough for 15 houses apparently and its supplies 2 and the farm which draws nothing until I start work!!

In fact it puts out near to 250v off peak times.

 

[skotl]

The idea of the fuse is not to overwork the cable etc.fuse the supply too high is kinda dumb! I have 100 amp to mine and an 80 amp fuse. Go get your 400 amp welder and run some measured 350amp runs off the single phase mains. This is something I was asking myself a few months back, found the answers and learned some things along the way, still looking for a big single phase MMA inverter 250 amp tec arc is the biggest I can find that a company will allow me to prove, saw Jims post on the lash up which got me thinking of other ways to skin cats though

Not exactly. The fuse is to protect the circuit so, assuming the circuit has been designed and installed correctly, there is no problem with drawing 63A on a circuit protected by a 63A breaker.

I'm not sure why we are (once again, and I don't mean you specifically, Kent) attempting to argue the laws of physics. If a reputable manufacturer states that their machine can kick out 400A, on a 52A input single phase supply, why are we less likely to believe that claim compared to the same manufacturer's claim for a 250A, 100A or 50A welder?

A reputable manufacturer is not going to keep that reputation if they make blatantly untrue statements.

 

[matt1978]

When I asked around from people in the know about 240 amps is all you can get from a mig despite what people state the set will do, limit is the input power you cant exceed. I can attest that poor supplies will limit this further, I had new lines put in from overhead (3 phase in case of future) but running single at present and a separate meter feed to the shop and it did give me better than previous at the hot end.

I think you also tested one of our M-Pro 252's? What did you get out of that?

We only have a 16 amp 230v in our demo area but even so, it has out-putted around 260-265a on the maximum voltage setting with a 1.0mm Steel wire using a 5% Co2 Mix.

 

[Kent]

Skoti ,
reputable is a strange word to choose. If the machine has a maximum duty of 400 amps it don't mean the supply can give it nor does it mean the seller is lying. Think on about 110v and 240v and their limits then think 415v. I think you mis understand my point and its the fuse should trip way before the safe load of the cable is reached on the supply, if not then we might as well replace the fuse with a section of 6" nail.

Matt,
Cracking set, tested it by the side of the C271 ESAB, didn't get to try it on 1mm just 0.8 , it basically ran out of wire speed on the thinner wire obviously a powerful set and I melted the torch and strangely not that much greater output than I suggest possible I will Likely buy one as a second set shortly to keep on 0.8 and argoshield light rather than universal as it was super smooth and almost spatter free (perfect for a job I have in the offing shortly). Currently I am Running a Kempi rated at 250 using it with 1mm this set will do a double side closed butt through 10mm meeting seamlessly, I am sure both the ESAB and the Lorch could also.

I know people respect your view can you give us the answer can a MIG be built that will run at 350 and over off the hot end off single phase single plug supply?

 

[skotl]

reputable is a strange word to choose. If the machine has a maximum duty of 400 amps it don't mean the supply can give it nor does it mean the seller is lying. Think on about 110v and 240v and their limits then think 415v. I think you mis understand my point and its the fuse should trip way before the safe load of the cable is reached on the supply, if not then we might as well replace the fuse with a section of 6" nail.

Of course the machine's maximum duty only sets an expectation of the supply requirement, not a guarantee that the supply will be adequate.
And, of course, 415v has much higher limits than 240v.

But my point is that a properly installed cable, with a likely CSA of 16mm2, will happily supply 63 amps all day long, assuming that this (or more) power is available at the consumer unit / distribution board, and that a 63A MCB is installed.
If a circuit is (properly) designed for 63A then you don't need to do anything to "de-rate" that supply and you can safely consume 63A from it. Incidentally, MCBs will trip at a level that far exceeds the actual capacity of the cable (5-10 times for B curves and 10-20 times for C curves).

That all said, you can absolutely consume 14.5KW from a 63A circuit (assuming 230V, closer to 15.7KW at 250V) so if you have a welder that is capable of consuming that level of power, then I would expect that the welder will output what the manufacturer states.

I guess the bit I'm having difficulty with (and I may be mis-reading what you're saying) is that you don't seem to believe the manufacturers claims, or that they could be fed that much power on a single-phase supply.

 

[Kent]

Of course the machine's maximum duty only sets an expectation of the supply requirement, not a guarantee that the supply will be adequate.
And, of course, 415v has much higher limits than 240v.

But my point is that a properly installed cable, with a likely CSA of 16mm2, will happily supply 63 amps all day long, assuming that this (or more) power is available at the consumer unit / distribution board, and that a 63A MCB is installed.
If a circuit is (properly) designed for 63A then you don't need to do anything to "de-rate" that supply and you can safely consume 63A from it. Incidentally, MCBs will trip at a level that far exceeds the actual capacity of the cable (5-10 times for B curves and 10-20 times for C curves).

That all said, you can absolutely consume 14.5KW from a 63A circuit (assuming 230V, closer to 15.7KW at 250V) so if you have a welder that is capable of consuming that level of power, then I would expect that the welder will output what the manufacturer states.

I guess the bit I'm having difficulty with (and I may be mis-reading what you're saying) is that you don't seem to believe the manufacturers claims, or that they could be fed that much power on a single-phase supply.

I don't actually know were I said this about the cable I have cable like an elephants trunk with an 80amp main fuse to my shop the spark said no more I believe him 100% and his reasoning, if your popping 80amps you have an issue and a potential safety issue at the point of supply.

Yes totally but its not I am saying they are liars just telling one version of the truth without the full story. Big capacity single phase is only about increasing duty at 250 ish amps not running beads at 300 plus. I should certainly listen to what Matt1978 has to say
Lorch have their biggest single phase mentioned above the 252 m pro
ESAB have the c271 as their biggest
The name though don't mean a massive amount but the point should be taken on board that neither of these major world manufacturers of welding plants has a 400 amp single phase

 

[daleyd]

Is that not just an indication that there probably isn't a market for that type of machine rather than the impossibility of producing one?

I can't see any logical reason why a single phase machine wouldn't produce that amount of current, when I worked at pilkingtons we used large single phase transformers to generate up to 2000 amps for heating circuits.

 

[wheresmejumper]

3 pages of head slapping nonsene

 

[PTvor]

Miller does a 400A single phase machine. Actually, it's single or three phase.

http://www.millerwelds.com/pdf/spec_sheets/DC12-51.pdf

Current draw 61A @ 230V.

Long ago there was a thread on here saying that machines up to 450A were available in 240V single phase.

http://www.mig-welding.co.uk/forum/threads/how-big-a-mig-on-single-phase.605/

One of the postings says that transformer MIGs are very sensitive to undervoltage, and if that's so, the local transformer or the lines supplying the premises weren't up to snuff there could be problems. With a good supply, there wouldn't be.

When you get to that sort of power you are definitely talking about industrial machines. Industrial premises almost always have three phase because much industrial equipment is three phase and it has all sorts of advantages at those power levels.

 

[harryb94]

Surely if you can run say a 250 amp machine on a 32 amp supply then with a supply rated at almost twice that there wouldn't be any problem with a higher powered machine producing much more than 250 amps??

 

[brightspark]

Surely if you can run say a 250 amp machine on a 32 amp supply then with a supply rated at almost twice that there wouldn't be any problem with a higher powered machine producing much more than 250 amps??

i realy dont get it. 80 percent of domestic supplies are minimum 60 amp mains fuse so unless u load everything else up at the same time u wont have any bother unless your in outlying aerias on long overhead lines and use the power at peak periods