Garage Feed

[m3wilson]

I have a Garage CU which has a 63A RCD incomer protecting 1x32Av (hot tub), 1x16A(sockets) and 1x6A (lighting) MCB.

The garage is fed via swa, what rating should the MCB in the main house be to feed the Garage?

Thanks in advance

 

[Steve]

What is the cross sectional area of the cores in the SWA, in mm²?

How long is the cable, from the house CU to the garage CU, in metres?

 

[m3wilson]

garage is approx 10m away, swa is 6mm.

 

[ericmark]

Table 4D4A shows 6mm direct in ground as 46A so likely a B45 MCB would be used but cable size is not the only consideration there is also volt drop and ELI and without the Ze and Zs reading this is a stab in the dark.

Also there are other types of SWA cable than shown in table 4D4A so that is just an approximate answer.

Why do you ask?

 

[m3wilson]

Many thanks.

The current 40A MCB in the house keeps tripping, just wondered if it was being overloaded.

 

[xr4x4]

Many thanks.

The current 40A MCB in the house keeps tripping, just wondered if it was being overloaded.

well if you add up the amps you get 54amps poss total draw...the hottub being 32amps needs a 6mm cable of its own.

what do you plug into the sockets? heaters? washing machine? tumble drier?

 

[m3wilson]

the sockets are only in use periodically, for general use such as a drill, sander etc, no heaters or tumble dryers.

Can anyone advise what size SWA cable and MCB would be suitable for such as setup.the hot tub does have a 6mm swa cable.

 

[electronicsuk]

Personally I'd go for 10mm on a 50A MCB, but I can't see how any of this is relevant as your question doesn't seem to make any sense. Many of your posts read as if you are going to be installing a new circuit to feed the garage, but in your first post you say that the garage is already fed by SWA. Are you upgrading an existing supply?

 

[m3wilson]

The garage is already fed by a 6mm SWA cable, but the MCB in the house keeps tripping, thinking it may be overloaded, hence the question on recommended SWA size and MCB.

 

[xr4x4]

says here that 6mm swa is good for 62amps....!!



i thought 40 amps was max.

 

[Adam_151]

I think in view of the hot tub load, and the fact that its best to only dig up the garden once, then it might be wise to go for 16mm² 3-core SWA feed from a separate switchfuse

 

[electronicsuk]

The garage is already fed by a 6mm SWA cable, but the MCB in the house keeps tripping, thinking it may be overloaded, hence the question on recommended SWA size and MCB.

If that's the case then it certainly could be overloaded - what's the size of the existing MCB for the garage?

 

[RF Lighting]

Why not put a clamp meter on the cable and find out?