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Generator to run tig welder

Portable Welder

Cast Iron
Joined
Jan 9, 2015
Location
Milan, MI
I just bought a 17500 watt generator that puts out approximately 78 amps, however the biggest plug is a 50 amp 230v plug and another one is a 30 amp 230v plug.
Looking at the electrical diagram both hots are on the same line, so I want to join them back together so I can give my Dynasty 300 the 61 amps to run at full capacity.

My thoughts are also to use it to run my welding shop since I just experienced 5 days without power.

I wire my machines in the shop all the time as well as having to wire them when I take them out to jobsites, so I know not to kill myself, I also know how to not over load the generator as well and both plugs are on circuit breakers as well.

I'm also thinking that once my amp load exceed 60 amps that the 30 amp breaker will trip which would give me enough power to run some lights and one welder.
Any thoughts of why I shouldn't tie my phases together ?
 
I just bought a 17500 watt generator that puts out approximately 78 amps, however the biggest plug is a 50 amp 230v plug and another one is a 30 amp 230v plug.
Looking at the electrical diagram both hots are on the same line, so I want to join them back together so I can give my Dynasty 300 the 61 amps to run at full capacity.

My thoughts are also to use it to run my welding shop since I just experienced 5 days without power.

I wire my machines in the shop all the time as well as having to wire them when I take them out to jobsites, so I know not to kill myself, I also know how to not over load the generator as well and both plugs are on circuit breakers as well.

I'm also thinking that once my amp load exceed 60 amps that the 30 amp breaker will trip which would give me enough power to run some lights and one welder.
Any thoughts of why I shouldn't tie my phases together ?

I would put the welder on the 50 amp plug and see if it does trip the genset's breaker.
 
You should be fine just using the 50 amp outlet. I run my weld shop on a pair of 30 amp 240 volt breakers and have never tripped them yet. But then again the most amps that I usually run is around 150. The voltage at the electrode is much lower than the 240 coming into the welder so 300 amps at your electrode is a lot less at 240 side.

I'm with DD. Try it with the 50 and see what happens. I've read that you can burn out some generators by trying to tie two legs together.

With all that said I have a 5K Coleman generator that I used for years to power our house during power outages by back feeding into my welder outlet. It has the small 240 volt outlets and I did tie them together after pulling it out and seeing that they were wired together already. It just took some load off of the small plugs.
 
digger doug, I was tig welding some 3/8" aluminum plate to 1" x 3" solid aluminum bar stock when the power went out, so I plugged the welder into my Trail Blazer that puts out 10,000 watts power, roughly 42 amps 240v, the best I could run was 200 amps and the Dynasty went into a help code, to get the car hauler out of my shop, I heated it up with my rose bud and then finished the weld.
So 200 amps was the best she had to give.
 
digger doug, I was tig welding some 3/8" aluminum plate to 1" x 3" solid aluminum bar stock when the power went out, so I plugged the welder into my Trail Blazer that puts out 10,000 watts power, roughly 42 amps 240v, the best I could run was 200 amps and the Dynasty went into a help code, to get the car hauler out of my shop, I heated it up with my rose bud and then finished the weld.
So 200 amps was the best she had to give.

Tell it to someone who gives a crap about helping you.
 
digger doug, theres nothing I said for you to be disrespectful, I was just giving you feed back about what happened when trying to power off a 10,000 watt generator.
Please dont respond to anything I post if your going to act like this !
 
Big B. Thats what I did as well, I kill my 200 amp main and back feed through my 50 amp welder plugs.

50 amps will run everything but my shear and press brake.
 
digger doug, theres nothing I said for you to be disrespectful, I was just giving you feed back about what happened when trying to power off a 10,000 watt generator.
Please dont respond to anything I post if your going to act like this !

Don't mind DD. He's just an ass____ that can't seem to get along with anyone. He's got over 22,000 posts and most of them are negative no help posts.
 
are you running the trailblazer with idle function or with no idle? If it is not tripping its internal breakers it is not giving 50 or 100 amps. The idle function has to be set to off to be able to give amps from go.
 
If there is a power factor capacitor bank that you can purchase for your Dynasty 300, that will make a difference in peak amperage used during welding.
I have a single phase Synchrowave 250, that is connected via 200ft of power wire that was only rated for 60amp, and fused for that. I've never tripped the main breaker with the power factor kit installed. And the distribution in my shop is on a 50amp breaker. Power factor capacitors will keep the reactive current in check. The kit from the OEM will have the correct capacitance for your welding supply transformer's inductance.
 
That's even legal ... so long as.. you use the "transfer" lockout plates made for the purpose.

- They are DIRT CHEAP.. compared to a "generator panel', a manual or an "Automatic" transfer switch.

- They don't take long to install.

- They might LOOK clumsy, but don't really even take long to switch, one mode to the other.

Most major load center makers have them for their goods. They aren't hard to find if one but looks.

My panel uses this one:

https://www.homedepot.com/p/Square-...erlock-Kit-QOCGK2C/203046553#product-overview

Obsolete panel? Search anyway. ebay might have it.

It can keep you out of a lot more expensive trouble than it's modest price!

Don't wanna?

No foul.

Just take your emergency load(s) directly to the gen set ... and stay TF OFF of the utility mains connected system.

Completely.

THIS.. is NOT one of the code provisions one casually fudges even briefly.
Powerco's are SERIOUS about backfeed violations. They need to be serious.

"Good intentions" or "I would never.." or "I know better than to.." aren't good enough.

Hardware has to prove and enforce it.

Be happy it is cheap.

Be happy you CAN easily stay off their wire.

We had wind storms here in Michigan last week and knocked out our power for 5 days. I did what I always do when we lose power for more than a few hours and pulled the meter, then hooked up my generator to the one of the welder outlets to backfeed the house. I don't have a main breaker.

When the power company came to restore power they just put the meter back in and never said a word about what I did, as usual.
 
Wot? Jealous because you only have 4,073 out of 4,074 no-help posts?

Figures...

Smart people speak because they have something to say. Fools speak because the need to say something.

I reference your over 20,000 babbling posts as termite and that doesn't count your posts as monarchist or any other personalities that you are using here.

Not much of a problem for me though as I usually skip reading your tripe.
 
You should look again at your gen set's manual.

Those are only "convenience" outlets built-in/onto most gen sets once you get above around 7500 Watts, 10 kVA and up almost always. 50 A is nominally 12 kVA @ 240 VAC.

Ex: My 10 kVA is lower-rated than your 17.5 kVA but has a 55A Circuit breaker, so would surely support more than your 50A just for connectivity. Sea-level rating SI 12 kVBA, and 15 kVA is known, proven, sustainable. But 17.5 kVA is NOT.

Most "serious" gen sets also have a set of split lugs meant for heavier wire.

All you have to do is find it and use it.

Whether you run #2 in buried conduit to a load center a hundred yards away to pull the whole house, or mount a NEMA weatherproof enclosure right at/on the gen set, and go on field manuevers - the flexibility to do whatever is needed should be already there. Not limited to just those two convenience outlets at all.

RTFM.

If no joy? Post the specific Generac details and let other eyes pull a manual and take a look, too.

Our man in Montana and I share a less than positive overall opinion of Generac, but still.

They purvey rather a LOT of gen sets - actually MADE by other people - and some of them are far better than others.

I've been using the same Generac generator to power our homes and sometimes our fifth wheel for over 15 years with the only problem being that the battery finally went dead after about 10 years. But termite said....
 
As usual, Big Blivet. More Bools**t that help.

You knew the model and rev number of HIS gen set for over 15 years ... all this time and never thot to share it so OTHERS could ken to WHICH Generac? WE didn't even know you two were sharing an RV.

I still say go and FIND OUT.

50 Amp connectors don't ordinarily grow organically right out of generator heads while still in the egg.

As usual you totally missed my point. My point is that just because you and some guy from Montana aren't huge fans of Generac generators doesn't make them bad generators. More bloviation from termite.
 
I just bought a 17500 watt generator that puts out approximately 78 amps, however the biggest plug is a 50 amp 230v plug and another one is a 30 amp 230v plug.
Looking at the electrical diagram both hots are on the same line, so I want to join them back together so I can give my Dynasty 300 the 61 amps to run at full capacity.

My thoughts are also to use it to run my welding shop since I just experienced 5 days without power.

I wire my machines in the shop all the time as well as having to wire them when I take them out to jobsites, so I know not to kill myself, I also know how to not over load the generator as well and both plugs are on circuit breakers as well.

I'm also thinking that once my amp load exceed 60 amps that the 30 amp breaker will trip which would give me enough power to run some lights and one welder.
Any thoughts of why I shouldn't tie my phases together ?


only reason I wouldn't, what happens if it back feeds the 50A through the 30A connector.......... fire waiting to happen. thats why you run one conductor only.
 
Here is how I would approach this. Someone please correct me if I am wrong.

Think of a generator being hooked up to a breaker panel with one wire feeding a leg with a 30 amp breaker and the same wire feeding a leg with a 50 amp breaker. In this case you could hook both hots together with no problems. They are already hooked together before they feed the breakers.

Now as to generators, most of the ones that I've dealt with either have two or four field coils. Most of those have two field coils and they only put out one phase. The ones with four field coils have two use two of the coils for one 120 volt feed and two coils for the other 120 volt feed. The advantage to having four field coils is that you can run them at half the rpm's of a two field generator. But it you tie them together you could very likely burn it out from the field coils working against each other or being out of phase with each other. The two coil generators are like the breaker box that is fed by a single feed wire.

With my old Coleman generator there is one set of wires feeding a single 240 volt receptacle with two outlets. I wired a pair of 240 volt plugs with pigtails to a small breaker box and a 6 ga extension cord coming out of it with a range outlet on the end. If I just used one of the small 240 volt outlets it would probably melt it down when I'm running a lot of loads but this allows it to use both outlets instead of one.

If you take the cover off and see that both outlets are fed by the same hot you can combine them. They are already combined inside and then split to both outlets.

I hope this helps.
 
Thanks for every ones tips / recommendations, I have the ability to kill the 200 amp breaker and lock the box so there's no chance of back feed.

I dont have the generator yet, there's a 150 day delay to get it, however, looking at the electrical schematic on line, its the same phase of power for both the 50 and the 30 amp plug !
 
just think of it this way. the power hot feed goes out through the 50A breaker then back feeds through 30A because that is the path of least resistance, it will melt everything as its is most likely sized to handle only 30A and not the heat from 50A returning to the neutral if that makes sense. doesn't matter that its hooked together inside. the weakest point will burn first and possibly take the generator coil with it.
 
I just bought a 17500 watt generator that puts out approximately 78 amps, however the biggest plug is a 50 amp 230v plug and another one is a 30 amp 230v plug.
Looking at the electrical diagram both hots are on the same line, so I want to join them back together so I can give my Dynasty 300 the 61 amps to run at full capacity.

My thoughts are also to use it to run my welding shop since I just experienced 5 days without power.

I wire my machines in the shop all the time as well as having to wire them when I take them out to jobsites, so I know not to kill myself, I also know how to not over load the generator as well and both plugs are on circuit breakers as well.

I'm also thinking that once my amp load exceed 60 amps that the 30 amp breaker will trip which would give me enough power to run some lights and one welder.
Any thoughts of why I shouldn't tie my phases together ?

I would not tie the two plugs back together; but I would check the wiring size for the 50A receptacle to find out if it will support the 78 amps.

NEC has exceptions for welding circuits since they usually don't have a long, steady power draw. Unless you are welding at full current from your dynasty, you should be able to support it on the 50A plug.

I have a Syncrowave 250DX that pulls around 70 amps when I'm TIG welding thick aluminum. I had to upsize the breaker and wiring for it, but the 50A plug and receptacles have worked just fine.

Since your Dynasty is an inverter machine, it will pull less amps than my transformer style.

Best of success to you with your project.
 








 
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