Your air compressor must need a lot of Amps in a big burst, to launch the 3HP motor. Running Amps are lower.
A MIG welder set to 100 Amps or less should work well. The initial arc strike might peak the input Amps for a split second. A portable welding service here runs a Miller MIG welder from a large generator (looks like 12 to 15 HP)
My 13HP generator starts and runs my 5 HP 240 Volt air compressor, but does not hold a good arc above 90 Amps on the Miller Thunderbolt AC/DC welding machine.
A MIG welder set to 100 Amps or less should work well. The initial arc strike might peak the input Amps for a split second. A portable welding service here runs a Miller MIG welder from a large generator (looks like 12 to 15 HP)
My 13HP generator starts and runs my 5 HP 240 Volt air compressor, but does not hold a good arc above 90 Amps on the Miller Thunderbolt AC/DC welding machine.
I have run my Lincoln 230 MIG on generator power. My generator puts out 5000 watts max, 4500 continuous and is powered by an 8 or 10 hp engine (don't remember without going out to the barn). Welded window frames made from 1/8 inch thick angle iron in to a 40 shipping container with no problem. Also welded in a chimney adapter made from 1/4 inch thick plate.
Yes I have used my 3500 watt generator to run a mig welder, welds came out nice. I did not overload the gen, and took extra rests to keep the windings cool in both units. I dont remember the voltage specs for the welder I think it was 20 amps/ 120 volts. and with my switch flipped to parallel the stator windings (120v only) we get a full 20amps (actually a little more) at that sinle outlet.
It takes alot of wattage to start those compressor motors, at least two to three times sometimes more than the rated running amps. Sometimes they print a starting wattage rating as well. Adding some resistive load helps, like a space heater. The induction motors are usually capacitor start, then we get cheapo generators like harbor freight who use aluminum windings, yes aluminum. That exacerbates a condition where the voltage lags behind the current, they get out of synch. I think its called capacitive reactance, power factor stuff.... thats why we scratch our heads when the generator says 3500 watts and the motor only 1500 and it wont start.....
I have a small compressor, which just hums when hooked to my generator, if I add in small a space heater 1000 watts in my case (just a big resistor) the compressor starts right up:shrug: That heater helps bring the amperage and voltage into synch, it helps the AVR automatic voltage regulator see what it actually needs to do.
It takes alot of wattage to start those compressor motors, at least two to three times sometimes more than the rated running amps. Sometimes they print a starting wattage rating as well. Adding some resistive load helps, like a space heater. The induction motors are usually capacitor start, then we get cheapo generators like harbor freight who use aluminum windings, yes aluminum. That exacerbates a condition where the voltage lags behind the current, they get out of synch. I think its called capacitive reactance, power factor stuff.... thats why we scratch our heads when the generator says 3500 watts and the motor only 1500 and it wont start.....
I have a small compressor, which just hums when hooked to my generator, if I add in small a space heater 1000 watts in my case (just a big resistor) the compressor starts right up:shrug: That heater helps bring the amperage and voltage into synch, it helps the AVR automatic voltage regulator see what it actually needs to do.
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ut:Today i tested the compressor with and without sideload, it runs from the other 230v output about 5 seconds then the generators overload relay kicks it off.
Same thing with the other output but it runs just 2 or 3 seconds before the relay kicks off, plugged it straight to generator:shrug:
What if i would connect the two 230v outputs as one would it just kill the generator or what.
Have a 2000w generator that cant be used for nothing, it cant even run a small anglegrinder properly so i could test it with it.
Same thing with the other output but it runs just 2 or 3 seconds before the relay kicks off, plugged it straight to generator:shrug:
What if i would connect the two 230v outputs as one would it just kill the generator or what.
Have a 2000w generator that cant be used for nothing, it cant even run a small anglegrinder properly so i could test it with it.
A 2000w generator will run lots of stuff, a 1200w microwave, hairdryers, various ligths, refrigeator,and lots of household stuff. But thats about it.
Anything with a motor hooked to a load will draw 2 to 3 times the runing amps when swiched on and ramping up to normal runing speed.
If a motor has a full load amp (FLA) rating of 12 amps, it would pull anywhere from 25-40 amps when speeding up from a dead stop. This varies on the type of motor and applaction, but they all do it.
Hooking up two 230v outputs together will still put the same load on the generator, you wont gain anything there. There is also a chance that you could cross phases and make a nice smoke mechine out of your generator.
A few tips when sizing electical loads to power sources.
Your total load in watts should not be more than 80% of your power sources normal runing capsity.
Some things do not give the wattage draw, only volts and amps. So dang, now what?
Voltage times amps = watts
Heres a example for a random piece of equipment that runs on 120v and pulls 11amps(my grinder). 120v X 11amps = 1320watts.
Throw in a few 120 watt work ligths, a fan or two, and a radio. You can add all the wattages up and find out how big of a generator you need.
Grinder 1320watts
3, 120 watt work ligths;120 X 3= 360 watts
Fan; 120v X 2amp=240 watts
Small radio may pull 50 watts
If we add that all up we get 1970 watts. A 2000 watt generator would get it done tell you squezzed the trigger on that grinder, slaming the generator with the 2-3x's the normal runing current.
Anyways hoped this helps.