Which certificate?

[pencilpusher]

I have changed the consumer unit in a kitchen. All done. I need to run new swa out to the detached garage to replace the swa thats already there. I am doing this so that I can avoid RCD protection at the house cu. Swa will be run inside and terminted in a box before running T&E to CU. My question is; what certificate do i use re the new swa to garage? I will not be touching any circuits in the garage. Thanks

 

[Mark_Burgess]

If you are changing the SWA which means either a larger or smaller size of CSA and length difference, then you really should fill out an EIC, as you will have affected the Zs values of all the circuits in the garage.

Why not install the swa directly into the CU?

By using the T&E to connect into the garage CU, remember the earth CSA will be reduced.

 

[pencilpusher]

Thanks Mark. The only reason for terminating in a box and then running to CU was because of the lack of room in the kitchen cupboard where the CU is. The swa at the moment runs with T&E through the kitchen wall to an adaptable box on the outside wall where it joins swa. To avoid having to RCD the swa (because garage CU is TT and house is TNCS) and discrimination issues I am changing swa to run inside the house.

 

[telectrix]

clear as mud. what size is the SWA as it's too big to take to the CU?