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Posted By Topic: Using 13A welders on 10A outlets

mwc54
Jan 23 2014 08:39

Not being registered I have concerns over the practice of using 13A (or higher rated) welders on 10A outlets. 15A outlets are installed but when individuals have to go to other sites 15A outlets are not available. The practice is to either use a 10A/15A pigtail or grind down the earth. Comments please?
   

zl2aj
Jan 23 2014 08:41

Grinding the pin down would make the appliance electrically unsafe (ESR 23 with new amendments)
   

AlecK
Jan 23 2014 09:16

An adaptor lead without current limitation is also electrically unsafe.

Using either of these unsafe work-arounds is an offence[ESR 15].
So is allowing one to be used.
And of course making the lead or grinding the earth pin is an offence [ESR 13].

Fine can be up to $10k for the individual.

That\'s just the Electricity Act, there\'s HSE Act as well.


The cure is a proper adaptor with over-current protection rated for the lowest-rated fitting used (in this case,10 A).

   

mwc54
Jan 24 2014 07:40

To the point. That answers my question. Thank you both for your replies.
   

dbuckley
Jan 24 2014 15:38

Mind you, a 10A type B MCB-in-a-box will still allow quite a heavy welder to be used, 30A for 30 seconds! So for tacking jobs, just fine. Welding a long seam, well, maybe not...
   

pluto
Jan 24 2014 16:35

dbuckley Jan 24 2014 15:38

Your comment
Mind you, a 10A type B MCB-in-a-box will still allow quite a heavy welder to be used, 30A for 30 seconds! So for tacking jobs, just fine. Welding a long seam, well, maybe not...

My comment
I think you mean a Type D MCB.

A type B operates at approximately 4 times the rated current in a very short period and is typically a thermal / Magnetic type and is quick operating.

A type D operates at 12.5 times the rated current and is generally a thermal only breaker only and takes sometime for the thermal sensing to operate.

See clause B4.5 of 3000.
   

dbuckley
Jan 27 2014 09:43

I\'ve screwed up there, no doubt. You\'d think I could read a chart by now.

But, as an anecdote: in my woodshed I have a power hacksaw, which has no starter on it, just a plug. (it came that way) When used, it is on the end of a 25M cable, the sort one gets from M10. As there is a light in the shed, one of those (again, M10) four way plugboards with integral 10A breaker is used.

Sometimes, the hacksaw will stall. The light dims. Clearly there is a lot of current flowing. And then the 20A MCB in the house opens. Its about 2 seconds. The integral breaker on the plugboard has never beaten the house breaker to open.

Perhaps it would on a long term 15A load...?
   

pluto
Jan 27 2014 09:51

dbuckley Jan 27 2014 09:43

Your comment (part).

Sometimes, the hacksaw will stall. The light dims. Clearly there is a lot of current flowing. And then the 20A MCB in the house opens. Its about 2 seconds. The integral breaker on the plug board has never beaten the house breaker to open.

My comment
The house MCB will usually be a type C MCB (Thermal/magnetic) and the EPOD will be a type D (thermal only) Circuit breaker.

MCB theory 101
   

mowgli
Jan 28 2014 19:29

The thermal/magnetic distinction is a red herring. \"about 2 seconds\" is almost certainly in the thermal trip region of a C curve MCB. Magnetic trip shouldn\'t occur until between 5-10x In.