Want to run a 120 volt welder off a generator?

It is possible that your generator has some receptacles built onto it that are rated for less than the capacity of the generator.

Here's what's important about generator rating, the total watts are often only achievable at 240v, only half of the watts may be available at 120. So a 3500 watt generator may only be good for about 14.5 amps at 120. However if your generator has a 30 amp 240v plug I would expect that the generator is likely sized above 5000 watts, because if it couldn't produce 5000 watts they would probably put a 20 amp 240v receptacle (20A x 240V = 4800 watts), so it's probably capable of at least 20 amps on 120v.

But welding off a generator is often difficult, the throttle doesn't respond fast enough for the generator to develop the current needed for a good weld, welders with build in generators regulate the engine speed different and keep the RPM's up higher.

The generator can deliver 30amp between the two sides of the 240 v, but that means that it has 2 - 15amp, 110v circuits. (after losses through the circuitry, it is safety down rated to 13 amps per side.) The 2 sides are out of sync and if you try to jump them together you will simply recreate 220v and destroy the welder and probably the generators internals. My recommendation is to buy a less than 30 amp 220 v welder, or a larger capacity generator.

You need to purchase a larger generator that will produce enough electricity to run your welder, this on is not large enough.

You are misreading something. If the generator can only supply 13 amps at 120 volts, it isn't capable of supplying 30 amps at 240 volts. Note: There is NO SUCH THING as the type of adapter you ask about.

What you need to do is READ the manual for your generator. I GUARANTEE if it can supply 30 amps at 240 volts, it can DIRECTLY supply 20 amps at 120 volts.

The wiring leading to the outlets cannot handle the higher amperage. You can damage the welder as it will not be getting sufficient power and/or overheat and start to melt the wiring on the generator,

If you use the 30 Amp output then your 120v adapter will have the Amp limitation but only up to 30Amp when the generator takes over the loading control

So if your adapter has a 20Amp limitation you r good to go.

I have just looked at your 'pigtail' and if you only use 1 tail to a 220v to110v transformer then the transformer must have the Amperage limitation you need

I'm ashamed of those who are saying you CAN do that. Truth is you CAN'T! Won't happen. Trying to do so will likely burn out your generator. So please don't try it.

Running it with only one lag off the 220 may burn up the generator.

No way.

i'm ashamed of those who are saying you can do that..................................................................................................................... truth is you cannot! shall not happen............................................................................................................... trying to do so shall likely burn out your generator...................................................................................................... so pleease don't try it...........................................................................................................................