Welder taking out MCB

[ash_s3]

Hi
I recently installed a supply for my mates welder in his workshop.
2.5mm SWA from existing TP Schneider DB to 16A wall mounted socket.
Protected by 16A Type C MCB.

Welder has a 16A blue plug attached and this is how it came from the manufacturer.
The breaker trips after one or two welds, i then upped it to a 20A C, same thing, then i went up to a 20A type D and still cant use the welder anywhere near full power.

Cable meggered out all clear (only a 10m run), nice low Zs, all connections double checked etc..

Surely if the welder comes with 16A plug attached it cant demand anymore current that 16A as that would overload the socket.

Im thinking faulty welder, any one any thoughts?

Welder is an SIP IDEAL 240.

Thanks

 

[Marvo]

Did you test the current draw with a clamp on ammeter? Maybe the welderis tracking internally across the windings. This wouldn't show up on an IR test.

 

[Guest123]

According to the manufacturers info, that particular model requires a 40A fuse for single phase.

 

[ash_s3]

Not had chance to test with clamp meter, its on another van.
Haven't IR tested the welder, only my wiring.

How can it require a 40A fuse and come fitted with a 16A plug? Where did you find this info please Lenny?

Thanks guys

 

[baldsparkies]

Lost count of the number of times I have seen a single phase mig welder on a 13 amp plug top, take out a 32amp ring main mcb. Open the plug top and there a nice peice of wire rapped around the fuse carriers prongs. These babies draw a lot of current. As Lenny says that model needs a 40A supply, and trust me, if handled badly they can take the DNO's HRC out no problem. Take care.

 

[ash_s3]

So i need 10mm SWA on 40A MCB with a 16A socket? Thats never right surely?
The thing has only got a 2.5mm flex on it!

 

[Mark_Burgess]

Here says a 50A supply. (the 's' model) 40A for the standard.

Wonderful thing Google.

 

[Guest123]

Here, 4th row down centre. Click on more info.


Tooltrade - tooltrade,sales,welders,mig,plasma,tig,arc,welder,cheap,online,sales

 

[ash_s3]

I did google it! 1st thing i did actually. Its an N model if that makes any difference?

 

[ash_s3]

Hmm... So if it does require a 40/50A supply, what am i terminating in? Can you get a 50A plug/socket?

 

[Marvo]

Yes, well, kind of, you get a63Amp plug and socket. Check out the Gewiss range on one of your local websites.

That supply cable at 2.5 mmsq isn't going to cut the mustard at 50Amps either.

 

[ash_s3]

The supply cable will obviously need to be upped to 6/10mm (havent looked it up yet)

What about the flex on the welder?

 

[baldsparkies]

Remember, these things are not your domestic friendly resistive loads. That highly inductive arc is caused by something close to a short circuit. Make sure the suppliers cut out fuse can handle it. As I have said on domestic supplies the standard HRC's used can easily be taken out.
You are upping your supply cables and your MCB's.
In doing so you are reducing descrimination between primary and secondary over current devices. Be carefull !!

Oh and in case you ask. Surge arrestor at the mains position. (I have found them capable of sorting the problem in the past)

 

[davelerave]

no chance this would be a 2phase model (aka 3-phase)

would have been better. on the tpn board anyhow

should be 1phase with the 16amp plug-but plug and lead don't seem to match SP specs

 

[Knobhead]

The supply cable will obviously need to be upped to 6/10mm (havent looked it up yet)

What about the flex on the welder?

Personally I’d return it as “not fit for purpose” and get a model that suits the supply. 40A is one hell of a whack for a home welding kit.

I can just imagine, Sunday morning he goes to do a bit of DIY while his wife puts the dinner in the oven. One DNO cutout launched in to space!

 

[Knobhead]

For some reason this PC has found a new trick. Have now got the fonts sorted, it’s started doing double posts!

 

[ash_s3]

Thanks Tony, this welder is being used in an industrial unit for a metal fabrication business so needs to be fairly hefty for welding 10mm plate.SIP have emailed me confirming it needs a 40a supply and the chap was unsure why it had a 16a plug attached! He Said the 2.5mm flex was ok as it only draws 40a for a small amount of time then settles to around 30a!!

 

[Knobhead]

The cable size still needs looking at, it’s too small.
Still your mate could wrap the flex around his mug to keep his tea warm.

 

[davelerave]

you would stand a better chance with the 20amp 3-phase model if it could be swapped at all


you may even get away with the existing 2.5 final circuit assuming it utilises only 2-phases

which i think is the case


why is a 40amp SP welder supplied with a 16amp plug and 2.5 lead? nothing surprises me with new equipment lately

 

[ash_s3]

Welder cant be swapped as its about 10 years old!

Can you get larger flex than 2.5mm sq?