This is my first TT/Outside job combined so any comments on my plan would be great ta.
Job: Power to outbuilding from house which is TT (Ze 36ohm).
Design current: 35.5A
Volt Drop: 3%
CCCapacity of SWA 50A (Ref meth D), 64A for 10mm t+e (ref meth C).
Plan:
1. Split tails and main earth.
2. L+N into 63A 100mA rcd, and earth into metallic block.
3. Take 10mm t+e - not using the cpc - and a 10mm single core earth from the metallic block, to outside the house where
4. It goes into a IP56 adaptable box and joins 10mm three core SWA.
5. SWA runs 40m - 6 of which underground - to outbuilding.
6 Inside outbuiding into JB where SWA joins 10mm t+e - not using the cpc - plus 10mm single core earth, all to garage c/u
7. C/U with 30mA mainswitch/30mA RCBOs for each way.
8. Test and anticipate a possible second earth rod for outbuilding.
Job: Power to outbuilding from house which is TT (Ze 36ohm).
Design current: 35.5A
Volt Drop: 3%
CCCapacity of SWA 50A (Ref meth D), 64A for 10mm t+e (ref meth C).
Plan:
1. Split tails and main earth.
2. L+N into 63A 100mA rcd, and earth into metallic block.
3. Take 10mm t+e - not using the cpc - and a 10mm single core earth from the metallic block, to outside the house where
4. It goes into a IP56 adaptable box and joins 10mm three core SWA.
5. SWA runs 40m - 6 of which underground - to outbuilding.
6 Inside outbuiding into JB where SWA joins 10mm t+e - not using the cpc - plus 10mm single core earth, all to garage c/u
7. C/U with 30mA mainswitch/30mA RCBOs for each way.
8. Test and anticipate a possible second earth rod for outbuilding.
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