T
The General
Hi everyone, apologies in advance, it's been a long day and I've not even had my lunch yet, so I'll try and keep this quick!
Running a supply to a wooden summer house, coming from existing CU on a 20A MCB with 30mA RCD as the main switch. It's going to run in 4mm 3-core SWA buried under a patch of garden and then terminated into a new metal CU in the summer house. I was planning to use the 3rd core as the main earth and there's no water/oil/gas services to bond.
I'm just questioning myself as I'm suddenly thinking that I also need to run in a main earth alongside the SWA back to the original CU?!? Or am I just going mad? Like I say, it's been a long day already.....
I honestly can't remember if the installation is TN-C-S or TN-S, but I can check tomorrow if it makes a difference. If I do have to run a new main earth then it'll be 16mm anyway as it would be buried without any mechanical protection (table 54.1)
Sorry for asking daft questions, but my brain is currently not functioning properly.
Thanks in advance for your patience and advice!
Running a supply to a wooden summer house, coming from existing CU on a 20A MCB with 30mA RCD as the main switch. It's going to run in 4mm 3-core SWA buried under a patch of garden and then terminated into a new metal CU in the summer house. I was planning to use the 3rd core as the main earth and there's no water/oil/gas services to bond.
I'm just questioning myself as I'm suddenly thinking that I also need to run in a main earth alongside the SWA back to the original CU?!? Or am I just going mad? Like I say, it's been a long day already.....
I honestly can't remember if the installation is TN-C-S or TN-S, but I can check tomorrow if it makes a difference. If I do have to run a new main earth then it'll be 16mm anyway as it would be buried without any mechanical protection (table 54.1)
Sorry for asking daft questions, but my brain is currently not functioning properly.
Thanks in advance for your patience and advice!
