i need to install a few gates and posts around the field, ideally i would like to concrete in a load of 4"x4" steel posts then go round and weld the hinges on and hang the gates once they are set, ive got an Rtec 181 which runs happily enough through a 13amp fuse in a domestic plug/socket in the workshop i would like to run this off a generator on the back of a trailer that i can drag around the field , but what size do i need in kva i guess ? in the dim and distant past i had a murex set and it never liked running off a generator what ever the size i dont mind if its overly large as it stops anyone walking off with it at what should i be looking ? thank you
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finyuk2005
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Generator Friendly - Generator must be minimum of 6KVA 240V and fitted with AVR (auto voltage regulation)
thats what it says on the website
BISON WHISPER MKII 10kVA SINGLE-PHASE DIESEL GENERATOR – Warrior Welders
www.warriorwelders.com
i have the non "silenced" version of this genny, and it seems to have plenty of power, even runs an old 240amp transformer based mig better than my shed, (need to fit a bigger mcb!)
hotponyshoes
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If it's a one-off job most hire centers will have generators cheap enough.
sardine
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My experience is that welders put too much load on sub 10kva generators and either kill the AVR on a regular basis , the AVR cuts out or the welder goes moody or it burn out the windings, if you're going to get a generator big enough to power a welder you as well get a welder generator with 110/220 v power for tools.
I'm selling all my generators and buying a proper welder generator.
I'm selling all my generators and buying a proper welder generator.
finyuk2005
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I definitely think a diesel genny does much better than a petrol one at the sub 10kva range, the extra torque and rotational mass makes them deal with big current spikes a welder like to produce much better than a small petrol, and any fluctuations is what will kill an inverter based welder especially!
I did have a parweld stick welder once, but i think running it 50 meter long extension reels that are only 1.5mm wiring killed it in no time!, lesson learnt, i made up 4mm extension leads and bought a Kemppi stick!
I did have a parweld stick welder once, but i think running it 50 meter long extension reels that are only 1.5mm wiring killed it in no time!, lesson learnt, i made up 4mm extension leads and bought a Kemppi stick!
A 6-ish kva genny will just about cope with a 160A or so transformer arc welder.
People bash on about AVR' on these small sets being essential to run welders.... but not necessarily true for lots of gensets.
Inverter welders use less power than transformer sets.... so a 6-7kva petrol GX390 Honda engined set is in with a shout of doing the job.
Inverter welders & capacitive voltage regulated generators..... hard to say for certain. UPS are very voltage & frequency fussy & like other Inverter drives create Harmonics that play havoc with the voltage regulation of small generators (they cause the instability then cannot cope with it).... but lots of non-UPS inverters also are pretty tolerant & have no issues with working off quite wide voltage & frequency bandwidths.
I've seen inverters work happily off a "dumb" capacitor regulated alternator, but refuse point blank to run off an AVR regulated variant of the sane power (my guess is that the faster-reacting AVR exacerbates the voltage fluctuation, where the more passive, slower-reacting capacitive version "damps" out the instability caused by the Inverter high-freqency switching).
Sometimes it's a bit of a black art - or an educated "suck it & see" exercise.
Note the small diesels 3000rpm ones (singles) max out at 10hp absolute peak, & don't have the flywheel mass etc to make any meaningful benefit.... where a Honda GX390 is rated at 13hp (though not quite that at 3000rpm). My money would be on the 1-cyl Honda outperforming a 1-cyl Diesel Yanmar.
If you want the safest "double the kva of the Inverter" advice (& the bigger the genny as a proportion of the non-linear load, the better your chances for sure).... then a Honda GX620 V-Twin at 20Hp & 10kva (8kw) is the cheapest and lightest way to get that sort of oomph.
People bash on about AVR' on these small sets being essential to run welders.... but not necessarily true for lots of gensets.
Inverter welders use less power than transformer sets.... so a 6-7kva petrol GX390 Honda engined set is in with a shout of doing the job.
Inverter welders & capacitive voltage regulated generators..... hard to say for certain. UPS are very voltage & frequency fussy & like other Inverter drives create Harmonics that play havoc with the voltage regulation of small generators (they cause the instability then cannot cope with it).... but lots of non-UPS inverters also are pretty tolerant & have no issues with working off quite wide voltage & frequency bandwidths.
I've seen inverters work happily off a "dumb" capacitor regulated alternator, but refuse point blank to run off an AVR regulated variant of the sane power (my guess is that the faster-reacting AVR exacerbates the voltage fluctuation, where the more passive, slower-reacting capacitive version "damps" out the instability caused by the Inverter high-freqency switching).
Sometimes it's a bit of a black art - or an educated "suck it & see" exercise.
Note the small diesels 3000rpm ones (singles) max out at 10hp absolute peak, & don't have the flywheel mass etc to make any meaningful benefit.... where a Honda GX390 is rated at 13hp (though not quite that at 3000rpm). My money would be on the 1-cyl Honda outperforming a 1-cyl Diesel Yanmar.
If you want the safest "double the kva of the Inverter" advice (& the bigger the genny as a proportion of the non-linear load, the better your chances for sure).... then a Honda GX620 V-Twin at 20Hp & 10kva (8kw) is the cheapest and lightest way to get that sort of oomph.
finyuk2005
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that one i have is a yanmar 1cyl clone, but they made it quite a bit bigger physically, and 15hp supposedly so id does do better than a 6kv pramac with a proper yanmar, like you say though, they are very heavy, and obnoxiously loud!!
Yes the real ones are loud enough to wake the dead, but the clones seem to clatter even louder!
Also although they are clones I don't think many (any?) Parts are interchangeable with Yanmar.
Weak starter motors as well - ideally you want to use the manual decompressor lever even with the electric starter, ad they really struggle.
thank you all for your replies, its more or less as i though go big or better still bigger still, how about old school lister style diesel generators i guess they would be ok they have some mass to them ? ok not really portable but i could trailer mount one,
i just found that pic on fb but i think i know where there is a smaller on than that , will investigate
i just found that pic on fb but i think i know where there is a smaller on than that , will investigate
Old Lister 1500rpm sets generally do pretty well. Alternators have plenty of mass, and being 4-pole industrial units have 2/3 pitched windings and generally AVR voltage control (though there were odd ones with transformer regulation to be found).
addjunkie
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Hire one of these
brandonhirestation.com
Or buy one of these
www.r-techwelding.co.uk
Home Page - Default Store View
brandonhirestation.com
Or buy one of these
MagicWeld 150M Petrol Welder - Mosa Engine
MagicWeld 150M Petrol Welder - Mosa Engine available from R-Tech Welding Equipment with fast UK delivery.
www.r-techwelding.co.uk
