Tom, it's like our (very) old 2 phase. Here we have 3 wires
with 220-230V between each phase and the zero/ground.
Depending how each phase is hooked up to an electrical
motor it's possible to make the motor spin in each direction
if two of the phases change places on the motor. All houses
here have 3 phase 380-400V and to load it equal, they split
them up to 3 groups of single phase 220-230V. The main
idea with 400V MIG-welders is that it's possible to use lower
rating main fuses to get more even current. I have not yet
tried a 220V MIG-welder here that can gererate this even
flow of current but development continues I guess. For gas
I use a CO2 & Argon mix (25%/75%) for mild steel, HE & Argon
mix (30%/70%) and TIG for stainless is Argon. All of these have
about 0.2% Mison gas added to reduce Ozone because it
gives me a sore throat after a while. Mison is common use in
welding gas here. The use of Helium for stainless MIG weldings
has been difficult since September 11:th since all Helium
comes from USA and the export permit office was in one of
the WTC towers.
Thomas
Thomas Walter wrote:
> Thomas,
>
> In the USA three phase is only brought into industrial
> areas (commercial area). Very rare to see any three phase
> power in the homes.
>
> All the houses here are wired for 220V single phase.
> Typically ovens, Air Conditioning, and clothes dryers are
> 220V, the rest of the house being 110V.
>
> The 110V is really a "split" 220V with a branch on both
> sides of a "common". It is a very odd way of doing things
> as to "balance" the load you really should have an equal
> amount of load on the two sides of branches, as current
> should not be flowing in the "common branch".
>
> Oh, I do have three phase motor's in my shop for the
> milling machine and metal lathe. Trick there is to use
> a switched capacitor to start the motor, then once it
> is rotating it will spin along nicely on the single phase
> power (at reduced power ratings). Doesn't work for
> something like a welder.
>
> Cheers,
>
> Tom Walter
>
> P.S. My electric vehicle used a three phase motor! ;-)
> DC (288V) was supplied by batteries to six IGBT switches,
> which created the three phase power to the trucks motor.
> http://www.austinev.org/evalbum/121.html to give an idea.
> Alas, truck stayed with Motorola. Still sitting there. ;-(
>
> Thomas - Sweden wrote:
>
> > The few suggestions I can give on MIG welders in general
> > (as someone who welds a few hours every day) is to get
> > a 3-phase current machine. We have 220-230 Volts on
> > 1-phase and 400 Volts on 3-phase in most parts of Europe.
> > I think USA are 110 Volts for 1-phase and 220 Volts for
> > 3-phase.
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