Circuit Breakers

[Luke]

I'm using my Portamig 211 on a 16A blue plug and socket, through a 16A type B breaker. It trips the breaker if i try and use the top three or so settings. not a problem, I knew it would, it's internally fused at 20A.

My question is this, i have read that 'inductive load' breakers - types C & D, are designed to withstand the in-rush current of the transformer, the trouble is finding one, especially for the garage consumer unit i have. Will i 'get away' with a standard 20A type B or will that not stand the start-up spike?

PS, I love the portamig, it's been a great tool to learn with. I went to help a mate out with some work and took the portamig rather than have to use his welder

Cheers

Luke

 

[cobminor]

How is the 16A socket wired in? If it has its own line with the right cable you could put a 32A breaker in.

 

[irondarren]

My 250amp mig runs on a type B breaker 32amp no problems, in theory it should be a 32amp type C but i have never once popped the fuse

 

[Luke]

The welder is on a 16A trip, the garage ring is on a 20A trip, both of those are on a 40A MCB for the garage.

 

[Omniata]

Try and get a single run off the 40A MCB to a 20A to 30A (25A if you can find one) breaker for the welder. Use nice heavy duty cable to make the run.

The idea is that the breaker trips before your cables melt...

Regards,

Jim.

 

[Luke]

This is what i've got in my garage.

power comes in to the CU on one bit of 2+E, the other bit of 2+E is the garage ring (ok its not a ring until about a foot of that 2+E.

The welder is on the end of the blue 2.5mm^2 arctic, with 16A plug and socket.

 

[Omniata]

You need to check what size cable that 2+E is running into the box and up it accordingly if it isn't enough to take the max load, then afterwards just upgrade the breaker to the welder to a more suitable one.

Whatever you do make sure the cables are rated well above the total current they'll be carrying.
It's not good to have a cable rated for just the welder then go and add the kettle and the toaster to it, if you catch my point.
The breakers might not all go but the cables will...

Make sure that the welders rated to receive the current you'll be able to throw at it aswell, if it can take it, it will.
A breaker close to, if not just below the welders max should be ok, unless you want to max it out regularly. (If you get one slightly lower it won't let you burn it out)..

Hope this helps,

Jim.

 

[Luke]

The supply to the garage CU is up to the job, i made sure of that when it went in.

Basically, it's all set to take a new breaker, but we're back to the original question, will a type B 20A do, or do i need to source a 20A type C or D that will fit my consumer unit?

 

[Omniata]

Apparently a type D is suitable for your welding machine, read "trip characteristics" on http://www.moeller.co.uk/ta_mcb_basics.htm look for "type D" and "welding machines".

Next buy one thats as close to the max current your welder will draw from the supply.

Hope this helps,

Jim.

 

[Luke]

20A type D it is then,

Next question, anyone know where i can find one! it's a volex CU, apparently the same pattern as Crabtree, can anyone confirm that?

 

[Omniata]

You'll have to read the label lol... Volex hasn't been given many good reviews on t'internet, labeled as cheap ... All the mcb's should be more or less standard tho...

MOD - sorry link removed at request of shop who seem to be having google issues.

There's a link to get one, you'll need to ask to confirm...


Hope I've helped, going to bed now. Work in the morning ...

Night all...

Regards,

JIm.

 

[Luke]

Cheap it was! It's doing fine for what i want though.

 

[malcolm]

To add some confusion into the mix:

I run my 181 off a 16 amp type B. Inrush current (seems worst when the transformers and capacitors fill up with electricity when you switch it on) hasn't caused a problem.

My enormous Syncrowave TIG kept tripping a 40 amp type B when it was stitched on, but was fine in operation. I fitted a 40 amp type D for that (allows a higher than 40 amps for a longer time than the type B) and it's fine on that. Bought it from an electrical trade shop - they needed to see the old one to match it.

Strictly speaking for top electrical safety you'd go for the minimum amp and lowest letter you can get away with reliably. I'd go for 20 amp type B or at worst a C.

 

[Robotstar5]

MCB's

Try looking for an electrical factor in your yellow pages like a branch of CEF, Newey & Eyre, Hagemeyer etc. Hope you've got one local

 

[cobminor]

That supply to your garage is not up to the job. That looks like 2.5 mm TW+E, (or even less) rated at 18A max. You also don't have a ring if both ends of it don't go into the fuse box. So, your ring main, which should take 32 Amps if wired properly is only good for 18 before the cables overheat. Your welder is on the same 2.5mm supply. You have 16A for the welder, now you only have 2A left for the ring sockets.

Putting another length of cable in to make it a proper ring is still no good as the supply line is 2.5mm.

Check the size of the cables, if I am right get an electrician to check it out, or even a good amateur.

Sorry about the opinion.

 

[cobminor]

That supply to your garage is not up to the job. That looks like 2.5 mm TW+E, (or even less) rated at 18A max. You also don't have a ring if both ends of it don't go into the fuse box. So, your ring main, which should take 32 Amps if wired properly is only good for 18 before the cables overheat. Your welder is on the same 2.5mm supply. You have 16A for the welder, now you only have 2A left for the ring sockets.

Putting another length of cable in to make it a proper ring is still no good as the supply line is 2.5mm.

Check the size of the cables, if I am right get an electrician to check it out, or even a good amateur.

Sorry about the opinion.

You also have 2.5mm cable on a 40Amp breaker, that should be a lot less.

 

[Luke]

It's not 2.5mm cable.

 

[big_d]

Luke,
I've got a 20A type B and a 16A type D MCB (breaker) in the garage. I've just been out to test them and the 20A will trip with a Portamig on full power but the 16A type D is fine. [never let it be said we don't do our reseach on this forum]


To source a 16A type D is a wee bit tricky but in Glasgow I used

http://www.rexelsenate.co.uk/w01-0829/cgi-bin/details.cgi?402. The one I have is Hagar but the specs are all similar; also they are all pretty much interchangeable.

You could also try someone like City Electrical Factors or go along to your local professional electrical factors for one.

Don't bother trying B&Q and the like, the Type D is too obscure for them [but at a push talk with their sparky sales guy; he might know a source!!]

 

[Luke]

Cheers Big D, that's the sort of answer i like, great to have some 'real-world' facts.

 

[cobminor]

OK, what is it then?