Welding off a portable generator

/ Welding off a portable generator #1  

STERLING351

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So i am replacing my fence on my property with 2-7/8 steel pipe for corner post and H-braces. In the past i have welded with a friends generator welder using 6011 1/8th rods at 90-100amps with good results. I was looking at a Powerhorse 7000w surge/5500w running generator ( https://www.northerntool.com/shop/tools/product_200664808_200664808 ). It has a L14-30 outlet so i found this ( Amazon.com : Conntek PL143 Welder Adaper Generator L14-3 Plug(4 Prong 3Amp) to NEMA 6-5R 5 Amp 25-volt Adapter Cord : Garden & Outdoor ) to adapt my welder to the generator. Do you think this generator will be enough for my needs, has anyone used Powerhorse in the past? They have good reviews.
 
/ Welding off a portable generator #2  
Depends on the welder. For many small inverter welders it would likely be enough.

I've run my Thermal Arc 161 off my old 5000/6250 generator with good results.
 
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/ Welding off a portable generator
  • Thread Starter
#3  
Depends on the welder. For many small inverter welders it would likely be enough.

I've run my Thermal Arc 161 off my old 5500/6250 generator with good results.

I recently bought a Klutch st200iDV to use for this since it small and portable which makes it fit in the back of my polaris ranger next to the generator hopefull for ease of transport.
 
/ Welding off a portable generator #4  
It's an inverter based machine so I'd bet it performs similar to my Thermal Arc on a generator.

You're only trying to burn at 100 amps so you won't be pushing the welder very hard.

I know a lot of people opt for 7500 watt continuous generators though.
 
/ Welding off a portable generator #5  
On the Hobart Welding Forum (Weldtalk) , they recommend a generator with about 50% more capacity that welder needs.... So if input side of welder requires about 20 amps (4800 Watts) at 240 Volts AC a unit capable of about 30 amp (7200 Watts) surges is best (numbers here sort of arbitrary for example) ... The thinking is start up surge (each time arc is stuck) of welder puts addition load (surge) on generator and it may bog down if its too small (slow to recover), because the rotating parts do not have enough rotating inertia/mass to keep up with load needs... Granted new inverters welder are better load wise but having generator to small can be more of a pain and makes work more miserable...

Wish people would not post Northern Tool links till board software does away with VIGLINK link hijack...

Dale
 
/ Welding off a portable generator
  • Thread Starter
#6  
On the Hobart Welding Forum (Weldtalk) , they recommend a generator with about 50% more capacity that welder needs.... So if input side of welder requires about 20 amps (4800 Watts) at 240 Volts AC a unit capable of about 30 amp (7200 Watts) surges is best (numbers here sort of arbitrary for example) ... The thinking is start up surge (each time arc is stuck) of welder puts addition load (surge) on generator and it may bog down if its too small (slow to recover), because the rotating parts do not have enough rotating inertia/mass to keep up with load needs... Granted new inverters welder are better load wise but having generator to small can be more of a pain and makes work more miserable...

Wish people would not post Northern Tool links till board software does away with VIGLINK link hijack...

Dale

So are you saying this welder is too small? I know at 200 amps output it requires 40amps input ar 220. I am unsure of exactly how much the draw is for 100amps output.
 
/ Welding off a portable generator #7  
So are you saying this welder is too small? I know at 200 amps output it requires 40amps input ar 220. I am unsure of exactly how much the draw is for 100amps output.

My Thermal Arc 161 welds very well at 125 amps from my 15-20 year old 5000/6250 generac generator.

Rent a generator for half a day and try it out for peace of mind - that's only about $40 here.
 
/ Welding off a portable generator #8  
So are you saying this welder is too small? I know at 200 amps output it requires 40amps input ar 220. I am unsure of exactly how much the draw is for 100amps output.

First ...

Watts are volts time amps...
240(v) x 10(a) = 2400 (w)


Amps are Watts divided by volts.
2400(w) / 10(a) = 240(v)

Take case of Lincoln tombstone welder, its a transformer welder.... Lets say at 100 amps it has a arc voltage of 24 volts...

Since welder is transformer model and for discussion we will say its a 10:1 ratio.... So 240 volts is stepped down through transformer to 24 (arc) volts, BUT this means as voltage is stepped down, amperage is stepped up (thank you Nicola Tesla) with a 1:10 ratio so a 100 amp output it relates to a 10 amp input....

Arc voltage and amperage needs to be calculated as to the conversion factor internal to welder (step down ratio)....

In your case you 200 amp output requiring 40 amp input (at 240VAC) would suggest you need a generator capable of a minimum of 9600 watts... IF you include the 50% factor you would want a generator capable of about 14400Watt

240(v) x 40(a) = 9600(w) (less 50% factor)

These are input values BUT everything changes when you adjust amperage (for electrode) up or down....

How ever if you are only welding at 100 amps you draw would be less (about 1/2 max draw) or about 4800 watt... So you would want a generator capable of about 7200 Watts (including the about 50% over wattage reserve factor)...

Hope I have not confused you more...

Dale
 
/ Welding off a portable generator
  • Thread Starter
#9  
First ...

Watts are volts time amps...
240(v) x 10(a) = 2400 (w)


Amps are Watts divided by volts.
2400(w) / 10(a) = 240(v)

Take case of Lincoln tombstone welder, its a transformer welder.... Lets say at 100 amps it has a arc voltage of 24 volts...

Since welder is transformer model and for discussion we will say its a 10:1 ratio.... So 240 volts is stepped down through transformer to 24 (arc) volts, BUT this means as voltage is stepped down, amperage is stepped up (thank you Nicola Tesla) with a 1:10 ratio so a 100 amp output it relates to a 10 amp input....

Arc voltage and amperage needs to be calculated as to the conversion factor internal to welder (step down ratio)....

In your case you 200 amp output requiring 40 amp input (at 240VAC) would suggest you need a generator capable of a minimum of 9600 watts... IF you include the 50% factor you would want a generator capable of about 14400Watt

240(v) x 40(a) = 9600(w) (less 50% factor)

These are input values BUT everything changes when you adjust amperage (for electrode) up or down....

How ever if you are only welding at 100 amps you draw would be less (about 1/2 max draw) or about 4800 watt... So you would want a generator capable of about 7200 Watts (including the about 50% over wattage reserve factor)...

Hope I have not confused you more...

Dale

no you did not confuse me more, you helped clear up some stuff. I contacted northerntools asking for a graph/info on the power requirements at different amp ranges but they still have not provided the info and I doubt they will. I did the same calculations as you did but was not 100% sure on my math so I figured I would seek input.
 
/ Welding off a portable generator #10  
I was pondering this at one time, the only conclusion I came up with is if I wanted to run even my inverter welder at max amps I would need about a 10K generator. For some reason you go over 8 KW on a generator the price increases to the point you might as well buy a welder/generator.
 
/ Welding off a portable generator #11  
I was pondering this at one time, the only conclusion I came up with is if I wanted to run even my inverter welder at max amps I would need about a 10K generator. For some reason you go over 8 KW on a generator the price increases to the point you might as well buy a welder/generator.
OR, buy a pto generator and run what ever you want, including your whole house.

I run my welder off my pto genset and it works perfectly. I like that I can set up lights to see better and also, someone can be running a side grinder while I weld.

SR
 
/ Welding off a portable generator #12  
no you did not confuse me more, you helped clear up some stuff. I contacted northerntools asking for a graph/info on the power requirements at different amp ranges but they still have not provided the info and I doubt they will. I did the same calculations as you did but was not 100% sure on my math so I figured I would seek input.

Try looking up graph in owners manual for welder, Hobart is pretty good about amperage outputs vs power requirements graphs, not sure about other welding equipment suppliers....... Welder information will be more precise in it requirement for selection of generator that will operate in your "working" range....

Also you may query online tech support (factory) for your brand welder and ask for generator recommendation....

EDIT: If your welder is Thernal Arc 161i (inverter) the manual on page 2-2 states recommended generator need ...

http://www.esabna.com/eu/literature...161 stl operators manual (0-5147)_nov2010.pdf


Dale
 
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/ Welding off a portable generator #13  
If you are in the market for a genny have you considered a welder generator? They work great
 
/ Welding off a portable generator
  • Thread Starter
#14  
If you are in the market for a genny have you considered a welder generator? They work great

Ive thought about it but in some areas on my property getting my big truck to them is pretty much impossible, my polaris does fine so im looking for a good portable setup that fits im the bed of my ranger.
 
/ Welding off a portable generator #15  
Ive thought about it but in some areas on my property getting my big truck to them is pretty much impossible, my polaris does fine so im looking for a good portable setup that fits im the bed of my ranger.

They have small welder generators. I used to have a Ranger 8 (8kW 100% duty cycle) which fit in the back of a pickup no problem. If you had a flat bed on the ranger you could probably carry it. I left mine on a pallet and just moved it around with my loader forks.

Engine Driven Welders | Lincoln Electric Canada
Miller Welder Generators - Engine Driven Welders and Machines - MillerWelds

There are smaller units you can pick up by hand too. At the time I got mine it wasn't much more expensive than a comparable duty cycle gas gen set.
 
/ Welding off a portable generator #16  
EDIT: If your welder is Thernal Arc 161i (inverter) the manual on page 2-2 states recommended generator need ...

http://www.esabna.com/eu/literature...161 stl operators manual (0-5147)_nov2010.pdf


Dale

Yep, that's the welder I've used on my 15-20 year old 5000/6250 generac generator.
The manual recommends a 6,000 watt genny and the one I use is just a little smaller.

Inverters are pretty darn stingy on power requirements compared to transformer machines.

If a person is unfamiliar with how big a generator is needed, I still recommend borrowing or renting a generator to test with.

But truthfully, I prefer welding with my miller bobcat 225nt instead of a generator + inverter setup.

Honda Ranger would easily pull a little trailer with a 500 pound welder/generator on it.
 
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/ Welding off a portable generator #17  
So i am replacing my fence on my property with 2-7/8 steel pipe for corner post and H-braces. In the past i have welded with a friends generator welder using 6011 1/8th rods at 90-100amps with good results. I was looking at a Powerhorse 7000w surge/5500w running generator ( https://www.northerntool.com/shop/tools/product_200664808_200664808 ). It has a L14-30 outlet so i found this ( Amazon.com : Conntek PL14365 Welder Adaper Generator L14-3 Plug(4 Prong 3Amp) to NEMA 6-5R 5 Amp 25-volt Adapter Cord : Garden & Outdoor ) to adapt my welder to the generator. Do you think this generator will be enough for my needs, has anyone used Powerhorse in the past? They have good reviews.

Purlins ok, drill pipe iffy. I find that using AC and an AC rod will make it (with a sloppier weld) than DC when at the generator's limit. I had a 5000 and it wouldn't work even with 3/32" rods. Then newer 6500 running watts does ok with 3/32 rods, barely on pipe. Clean material to be welded really makes a difference.
 
/ Welding off a portable generator
  • Thread Starter
#18  
Purlins ok, drill pipe iffy. I find that using AC and an AC rod will make it (with a sloppier weld) than DC when at the generator's limit. I had a 5000 and it wouldn't work even with 3/32" rods. Then newer 6500 running watts does ok with 3/32 rods, barely on pipe. Clean material to be welded really makes a difference.

I grind the immediate area to be welded first so it is alittle cleaner
 

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