Welcome to the forum. Although you can post in any forum, the USA forum is here in case of local regs or laws
No Part P up here 😀
If there is a ring main close by I would take the spur from the ring main, the cable should be the same size as the ring main I.e. 2.5 mm t&e, the ring main protective device would suffice, and then the spur should be fused to protect the appliance as required.
Should I have to go back to the board for a new circuit then again 2.5 mm t&e, protective device for this would be 16amp then again fused at the spur to protect the appliance.
If you read the text you will see that the 16 amp is to protect 2.5mm t&e, 32amp is to big to protect 2.5mm as a single circuit.
depends on what circuit type it is 😉
That was why I asked the question. 2.5mm from the board on a 15amp 3036 rewireable fuse to the immersion. Then a 1.5mm from the spur to the boiler with a 3 amp fuse at the spur. Just thought the 15amp at the board should be changed to a 6amp.
He's not converting a radial into a ring he was asking where we take a spur from, and how we size the cable,
So the 15amp at the board will protect the 2.5mm and the 3amp will protest the 1.5mm from the spur.
As a single circuit, I.e. From the board to the appliance (not a ring main) then the maximum current carrying capacity of 2.5 mm t&e is 27amps when ref.method C is used, a 32amp breaker would therefore be too big.
No, the 15amp protects the circuit the 3amp protects the appliance fitted, in this case the boiler
Good example of how a simple question can involve complex considerations. Next someone will ask is the cable surface mounted or surrounded by rockwool.
or chased in 😀
Sorry, I thought the 1.5mm was also t&e, 1.5mm flex is very big for a boiler,
Reply to the thread, titled "fused spurs" which is posted in UK Plumbers Forums on Electricians Forums.
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