Oxford RT110

[N16KWA]

Hello there. I'm new to welding, having recently achieved a lifetime's ambition of learning to weld at night school.

I was going to buy a Clarke MIG 135 TE, but a friend of mine offered me his Oxford Oil Cooled welder. I probably paid over the odds for it, given that the cables had no protection and I've had to replace them with nice new ones, but better to do that than receive a 'shock'! I have also rewired it with a 32 amp plug and armoured cable. I have had a 32amp switch socket installed by an electrician in the garage with a 32 amp fuse.

So, last weekend I prepared myself for a bit of a practise. I grinded some steel back to its shiny glory, switched on the welder and........ trip went the fuse. I re-set everything and re-started and trip it went again. I turned the amps down to about 55 and re-started and it hummed into action, but think I was too nervous to strike an arc thinking it was going to trip so gave up and packed away.

I've taken some photos of my set up and will upload later, but wondered whether putting in a C32 or D32 MCB would solve the issue? The electrician says he installed the 32 amp socket with 6mm cable and the distance from the socket to the fuse box is no more than 18 inches.

Can anyone help please?

Thanks

Nick

 

[zardoz]

can you make sure that take a pic of the data plate and/or the top of the Oxford.

 

[super noob]

what class is your breaker ? I had a problem using my astonarc until it got upgraded to a C class

 

[julianthegypsy]

I've used the 140 off a 13 amp plug, it blew fuses occasiobally at higher settings but was otherwise ok! If you can get it sorted, you have a far better welder than the clarke.

 

[brightspark]

the welder will run fine of a 30amp rewirable fuse but will take a 30 amp b type mcb out just on plugging it in before welding . so theres your answer change it to a c type or a d if u have 2

 

[N16KWA]

Thanks for the replies. Here are the pictures of my set up.

 

[Paul99]

There's your problem it's only a domestic (B-rated) 32 amp breaker which just can't cope with the high inrush current the welder asks for. You need to have that breaker changed for a C32 of D32 or you'll always have the problem with it tripping.

Some background reading here: http://en.wikipedia.org/wiki/Circuit_breaker#Standard_current_ratings_for_Europe

 

[N16KWA]

So, if I fit a D32, I can crank it up to the full 110 with no problem?

Also, is the 6mm cable in the black pipe sufficient or would that need upgrading to say 10mm like for an electric shower?

 

[N16KWA]

Also, someone has said I shouldn't be putting in a D32 on a domestic circuit. That's rubbish isn't it?

 

[RonA]

I own an Oxford 180A oil cooled welder, great welder but I had to run it off a cooker socket & fit a power factor correction condenser to avoid blowing fuses.

 

[Paul99]

I regularly run my oil cooled welder at 100amp+ off a 40amp C rated breaker (32C would have done - but the electrician used what we already had). You should easily be able to run that welder flat out on a 32C or a 32D if you want to spend the extra - I've never heard of rules against adding a C or D breaker to a domestic circuit (definitely no physical reason to stop you anyway) but as I'm no electrician you need to check with one - probably not the same one as before as he should have known a 32B would cause problems with a welder IMO.

As for cable again I'm not sure of regulations or more importantly whether you could get away with 32amp through such a short length of 6mm but for such a short length I'd not think twice about swapping it for 10mm TBH.

 

[brightspark]

Also, someone has said I shouldn't be putting in a D32 on a domestic circuit. That's rubbish isn't it?

no its not rubbish try the c type breaker 1st and 6.0mm cable will well cover it

 

[BillJ]

no its not rubbish try the c type breaker 1st and 6.0mm cable will well cover it

Indeed, it isn't rubbish but there are considerations to do with the rest of the house wiring that will dictate whether or not it is safe to fit a D32. We can't tell what those are from here. It is certainly unusual to find a D32 fitted in a domestic circuit. Why not ask the electrician who fitted the 32A socket since he should know how the rest of the house is wired?

Regarding the welder tripping the MCB on switch-on, I often have this happen with my little Aldi buzz-box on a 16A socket and breaker. Even a C16 didn't stop it. However, turning the current right down before switching on, as you did with yours, also works on mine. Once switched on I can set the current as I want and start welding without problems. After running for a while I can switch it off and on again without tripping so it seems only to be the cold inrush current that causes the problem.

 

[N16KWA]

Thanks for your replies. The electrician has ordered me a C32 fuse and will be fitting next week so I will update you on the outcome then. Failing that, I'll have an Oxford for sale with nice new leads!

 

[N16KWA]

All up and running now with the help of the C32 fuse. Many thanks for all your help. Sorry for posting in the wrong section.

 

[zardoz]

Good to hear. They are fine old machines, I learned at college to Arc weld on one of those. (I also used to own one, but unfortunately for me I apparently bought the worlds only Oxford machine that would not also work with 230 Volts, so it had to go)