10 replies to this topic

[Bobbins]

I’m considering adding a dedicated socket to the house consumer unit to enable my MIG to have a higher current source than a standard 13A socket, is it usual to add a 16A, or will it need a 32A (round pin) socket? If I eventually buy a spot welder I’ll certainly need one!
I assume it’s fine to then run a suitable extension cable to my workshop where I’ll be welding, the workshops power is already fed from the house so I’m limited to a 13A plug in the workshop.

[elliot341]

Most migs you can run happily off a 13a. I'm even running my spot welder off a 13a connection, occasionally if trips but only if I don't have everything perfectly clean and set up well.

[nicklouse]

Most will be fine on a standard 13A plug. But check the specs of the Mig as some do need 16A.

Edited by nicklouse, 30 August 2021 - 11:43 AM.

[whistler]

If I remember my electrical theory correctly a load (mig welder) will only take what power it needs from a supply. If it wants or tries to take more from your 13A circuit then it will trip the breaker in the consumer unit. I run my mig (Clarke) from a standard 13A socket and also have used a fully unwound extension lead.

[Steam]

Depending on the distance, an extension lead may be worse than your existing power feed to the shed / workshop.
I doubt you would be using much in the shed other than rhe welder so the supply to the shed should be sufficient.

[GraemeC]

Do you know the cable size feeding the shed?  It may be large enough to support a 16A circuit (you'd also need to know the approx length of cable to factor in any derating).

[Ethel]

Depends what your toys are rated at - you'll need circuit protection to match: no 16A mig running directly off a 32A breaker or 30A spot welder off  16A (it'd be safe, but you wouldn't make many spot welds  )

 

2.5mm² is the "generic" cable size (likely to be found embossed on the sheathing) for most domestic applications, it'll carry 16 amps on a spur & 32 amps on a ring, which is supposed to do 4 sockets, but often has a lot more. If your existing wiring is tapped off a ring main for your house sockets you'd just be adding to that limitation. It's worthwhile as a dedicated connection to your consumer unit as you can have a breaker instead of blowing a fuse if you ground your torch.

 

As said, you really need to calculate the requirements, particularly if there's any sort of distance in the cable run, it needs armoured cable etc. There are online calculators that'll do the maths for you, but you ought to be talking to a sparky if you want to open your consumer unit & have it properly certificated. At least you can weigh up your options 

[Bobbins]

Thanks for the information and suggestions. I have an electrician coming to do some lighting changes hence looking into this now, it’s an opportunity to to have a socket fitted properly and fully certified to the regs.

The house wiring is safe but certainly not in my mind satisfactory, only one circuit breaker for both upstairs and downstairs sockets, the central heating boiler is fed from the upstairs lighting circuit which baffled my plumber, you get the picture! Also the shed/workshop electrics are fed from a B16 circuit breaker whereas the house sockets are protected with a B32.

My welder is a R-Tech MIG 180 which will run off a 13A plug but only if I’m careful with the settings, hence looking at a dedicated supply. Unfortunately the consumer unit is at the opposite side of the house to where I’m welding the Mini and will need around a 20m extension cable, the spec needed of extension cable I think is likely to determine the socket needed?

[Ethel]

That'll be a ring vs a spur. May as well use what you already have which is enough for sockets, or your welder but not both at the same time. If you split your house ring in to upstairs & downstairs could you stick the shed sockets on the upstairs ring? If you're in the shed you won't be in bed  . You could then convert the existing line, just for your welder, with a commando socket.

[GraemeC]

You have a spark coming round - tell him what you want and let him advise.

 

Running a 20m extension cable just sounds impractical and a hassle.

[Bobbins]

You have a spark coming round - tell him what you want and let him advise.

 

Running a 20m extension cable just sounds impractical and a hassle.

 

I suspect that's what I need to do.

 

The extension cable I'm referring to is a heavy duty commando socket type specifically for the welder, I'm thinking this would avoid putting any increased load on any of the other circuits.