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View Full Version : 211v enough for MIG??



benboy
23rd Aug 2006, 05:42 PM
Hello everyone
I live on a farm where the power supply is second rate to say the least. Testing the 15amp power point in the farm workshop shows only 211 volts coming through, and that's during non-peak time. Is that enough to power a small mig (say a Lincoln SP 175t)? Bear in mind that I only want to use it at the lower end of the scale for sheet metal work (I have a Lincoln arc welder/generator for the bigger stuff). I have a feed bin project in mind that involves a lot of butt welding of 1mm galvanized sheet, that's what I wanted the mig for.
Also, I understand the Lincoln SP 175t is a "tapped" model. Would that be OK for 1mm work or is "infinately variable" amp setting the way to go? Do any of the small mig machines have "infinately variable" as a feature, as the few models that I've looked at on the net don't seem to.

Thanks
Benboy

Buzzer
23rd Aug 2006, 06:22 PM
Hi Benboy,

Welcome to the forum.

I too live on a farm, although I am not an electrican, around here they are few and far between. That leaves me to try and diagnose problems the best way I can.

211 volts sounds way too low to me, to run anything meant for 240v. If that is the no load voltage, it will drop even further under load.
I had the same problem and to cut a long story short, the electricity supplier had to replace transformer and pole earth wiring(swer line). This fixed the problem and no load voltage is now 245.

Cheers
Buzzer

Eddie Jones
23rd Aug 2006, 06:27 PM
Running anything containing a transformer on 211v when it should be 240v is going to generate excess heat. The device MAY sort of work, but you are sure to limit it's life

Auld Bassoon
23rd Aug 2006, 07:50 PM
211V sounds very low to me. Although no electrician, I do have a basic understanding of the various elements involved.

Running a transformer from an input 211v might work, but would put a heat load on the kit. I would also wonder on the effects it might be having on domestic kit if that same voltage applied.

Methinks a call to the elecktrickery distributor might be in order...

Grahame Collins
23rd Aug 2006, 08:33 PM
Benboy,
I understand there is a legislation existing where the electricity supplier should guarantee that electrical supply should not vary by a a factor of more than ten percent. 240 volts minus 24 equals a minimum of 216 volts that should legally be available.If that is the case in your neck of the woods, perhaps fact or not may be verified through contacting an electrical contractor.
You could then feel justified in taking up the matter with the supply authority.
Is your welder at risk, may be? But wait there's more !

Crikey! of much greater concern to me would be your household appliances that can be affected by low voltage.Refrigerators and freezer compressor motors come to mind.
Does n't OHM's law apply and low volts will affect the amperage drawn which will increase and sooner or later damage the compressor motor ? Perhaps an electrician might elaborate here?
I have my fridge freezer protected by a low voltage cut switch installed by an electrician.Contact your local leccy for details.

I hope it helps
Grahame

bsrlee
23rd Aug 2006, 09:19 PM
Dependant upon your state, but I was advised by a NSW techie that here its a minimum of 240 volts or else - if they supply low voltage the amps drawn go up & the meter supposedly runs faster. One of the old NSW 'County Councils' got into strife as they were supplying some areas with 180 volts.

Schtoo
24th Aug 2006, 12:33 AM
Nope, not enough by a long way.

How many wires are running to your meter? If it's only one, then it's a swer system (as mentioned) and since the ground is pretty dry you are getting a bad neutral line, dropping the voltage. That's no good and way under regulations (+-5% IIRC).

If there is more than one wire, something is amiss and needs looking at. Might be a bad connection somewhere (fire hazard!), undersize wiring (dodgy sparky) or some other unknown affliction.

Either way, give the power company a call and ask them come out and look at it. If it's their fault, they will fix it. If not, they should give you some suggestions on what to do to get it fixed. Maybe to the point of hunting down the iffy sparky to install proper sized cable.

(If you wired it yourself, then you gotta remove all evidence before they show up, and there won't be a problem for them to look at... ;) )


Just to give you an idea, we ran some cable for a fire pump shed, just some radiant heaters, control wiring for the pumps, lighting and a power point. The run was from the main switch baord, which was connected to a large transformer and was about 250m. The cable was 185mm2, which is about 3cm thick and all that to run about 20A of juice per leg. The cables are rated at about 200A, but the size was needed to avoid voltage drop, which is the problem you seem to be having.

If you need cable that big, might pay to look into a separate wire feeder setup for your genny welder.