Wiring garage supply, breaker size recommendations for welder.

[starmag]

Hi guys, I'm planing on putting some power to my grandparents garage so I can work on my car. I'm going to put in one double socket which will be running a freezer, and my welder too, and then a couple 5ft fluorescents or x2 battenholders.. whatever gives the best spread of light?


The thing I'm unsure of which size breakers to use. The garage is detached so the plan was to put in a sub main using a 6mm 3core armoured fed from the main consumer unit on a 63A mcb? Then have this going to a garage consumer unit with a 63A 30mA RCD main switch.. 6A breaker for lights.
Then for the socket, because of the high current drawn by the welder, do I:


1. Type C 20A breaker, radial circuit, 2.5mm
or
2. Type C 32A breaker, ring circuit, 2.5mm

Or do i run a circuit just for the welder socket?

What's your thoughts?

Welder specs below (Clarke 150te)

Any advice is much appreciated.
Thanks, James

 

[Marvo]

A 63A MCB on a 6mm cable is a bit hairy for my liking.

Lets start at the beginning, what earthing arrangement is the main house?

 

[Octopus]

Here we go again. Have you consulted your OSG or BGB?

 

[MDJ]

eh? sorry what was that again??

 

[Darkwood]

Yep the 6mm jumped straight out at me ...has the OP missed a 1 of it ?..... If not i'd be inclined to polish the mirror first before you add the make-up.

 

[starmag]

Sorry guys, meant to post this in the DIY section but couldn't? I did my level 2 years ago but never got round to finishing my apprenticeship because the company I was working for went bust, so I'm a bit rusty, sorry

 

[Marvo]

No probs, I've relocated it for you.

 

[Octopus]

New circuit = Part P = Building Control Notification.

 

[Darkwood]

Do your cable calcs to derate the front end mcb of the supply to the garage... best advice is ring manufacturers up regarding mcb sizing i suspect the fuse (20) it relates to could be cartridge style as you may have picked a welder better suited to a workshop not a domestic garage.. again just contact supplier and query this point i may be wrong but inrush current on welders can be high.

 

[starmag]

Thanks Marvo, sorry I missed your question about the earthing arrangement. It's TN-S.

would a 32A be more suited to feed the garage supply?

and as for missing the 1 from the 6mm. What do you mean by that? Surely a 16mm armoured would be a bit overkill? The welder is only a standard plug top

 

[starmag]

Clarke 150TE (Turbo) MIG Welder - Machine Mart

 

[Darkwood]

Thanks Marvo, sorry I missed your question about the earthing arrangement. It's TN-S.

would a 32A be more suited to feed the garage supply?

and as for missing the 1 from the 6mm. What do you mean by that? Surely a 16mm armoured would be a bit overkill? The welder is only a standard plug top

Not knowing the size of the house, garage or incoming supply all we had to go on was the 63amp mcb you said it had ... 16mm may be overkill but with all due respect the fuse protecting the garage supply is overkill and a fire hazard on a 6mm cable if you developed an high impedance fault.. (overload unlikely in the circumstances of the circuits you listed).

You spec' us a 150TE which is not on the list you posted as the nearest one is a 150T3E on a 20amp fuse but you now say its on a plug top ...conflicting info or you haven't posted the correct spec for your model.

We can only go on what you tell us - be aware we don't know your install except for what you tell us ... i've seen garages before with 16mm ..when you take into account install methods (especially ducting underground) length of run etc etc a cable can easily get to larger sizes even with a 40amp front end device.

 

[Darkwood]

Clarke 150TE (Turbo) MIG Welder - Machine Mart

Now we have the spec' of the correct model - check the power supply requirement it states then consider that plug tops only go up to 13amp...

Quote - require 15amp power supply minimum!