UK MCB Size for radial socket circuit.

[nicebutdim]

Just wondered why you recommended 1.5mm and 16A. Seems a bit tight for 4 double sockets.

Especially when giving advice to someone who seems very unsure of what they're doing.

 

[Electrics]

Just wondered why you recommended 1.5mm and 16A. Seems a bit tight for 4 double sockets.

I'm not, i'm just saying it can be done. 1.5mm and 16a will handle 8 doubles. That's how the French do it and i'm presuming their normes are safe. Electricity is electricity after all.

If i were doing a radial i would use 2.5mm and 20a, but at the end of the day i just like to answer the question seeing as there could be variables at play we don't know about. I was just answering the question 'all i need to know is will a 16 Amp MCB be sufficient for the socket Radial circuit for 4 Double sockets'. Answer is yes.

 

[Electrics]

Especially when giving advice to someone who seems very unsure of what they're doing.

I hardly think that makes a difference. Safe is safe whether the person knows what they're doing or not and 1.5mm @ 16a will be fine for 4 sockets in a shed assuming he's not going to be running a load of bench tools off them all at the same time.

 

[nicebutdim]

I hardly think that makes a difference. Safe is safe whether the person knows what they're doing or not and 1.5mm @ 16a will be fine for 4 sockets in a shed assuming he's not going to be running a load of bench tools off them all at the same time.

I didn't raise any questions about safety.

 

[pc1966]

I hardly think that makes a difference. Safe is safe whether the person knows what they're doing or not and 1.5mm @ 16a will be fine for 4 sockets in a shed assuming he's not going to be running a load of bench tools off them all at the same time.

Its for dog grooming. I would not be too surprised if it has in winter a heater, kettle and hair-dryer all on at once so would go for at least 20A 2.5mm radial.

 

[Electrics]

I didn't raise any questions about safety.

So i'm not sure what you are actually saying at all then. He doesn't know what he's doing therefore i should not answer the question he asked? Confused sorry.

 

[Electrics]

Its for dog grooming. I would not be too surprised if it has in winter a heater, kettle and hair-dryer all on at once so would go for at least 20A 2.5mm radial.

Yeah me too.

 

[nicebutdim]

So i'm not sure what you are actually saying at all then. He doesn't know what he's doing therefore i should not answer the question he asked? Confused sorry.

Re-read the OP's comments prior to the point you suggested a 16A radial in 1.5T&E, then decide if sufficient information had been provided to determine whether or not such advice was appropriate.

 

[Electrics]

Re-read the OP's comments prior to the point you suggested a 16A radial in 1.5T&E, then decide if sufficient information had been provided to determine whether or not such advice was appropriate.

From the information provided by OP in this thread about what he wants to use the sockets for, 16a 1.5mm is fine. I wouldn't do it that way i would use 2.5mm and a 20a breaker but OP asked a question and i simply answered it. I also conceded already that it depends what it's going to be used for. 16a radial on 1.5mm can easily handle 'trimmers and a hair dryer'.

The answer to OP's question about 'can i use a 16a breaker to run 4 sockets' is 'yes'.

 

[Toonjabba]

From the information provided by OP in this thread about what he wants to use the sockets for, 16a 1.5mm is fine. I wouldn't do it that way i would use 2.5mm and a 20a breaker but OP asked a question and i simply answered it. I also conceded already that it depends what it's going to be used for. 16a radial on 1.5mm can easily handle 'trimmers and a hair dryer'.

The answer to OP's question about 'can i use a 16a breaker to run 4 sockets' is 'yes'.

Thanks everyone for your comments I will take on board everything that has been said. I do have 17th edition cert and part p but was done a while ago and not had much experience. I just wanted to make sure it’s safe. I will be using 6mm SWA from house to shed then 3 separate circuits for lights sockets and 3 kw water heater. What MCB would you suggest using in the house CU.

 

[telectrix]

Thanks everyone for your comments I will take on board everything that has been said. I do have 17th edition cert and part p but was done a while ago and not had much experience. I just wanted to make sure it’s safe. I will be using 6mm SWA from house to shed then 3 separate circuits for lights sockets and 3 kw water heater. What MCB would you suggest using in the house CU.

40A MCB, assuming SWA is installed ref' method C, clipped direct with no insulation preventing heat dissipation.

 

[brianmoooore]

It would be preferable (to get better discrimination), to feed from a switch fuse at the house end, rather than a MCB.

 

[Toonjabba]

40A MCB, assuming SWA is installed ref' method C, clipped direct with no insulation preventing heat dissipation.

Thank you.

 

[pc1966]

It would be preferable (to get better discrimination), to feed from a switch fuse at the house end, rather than a MCB.

It would do.

However, I would suggest fitting at least one emergency style light (part of strip lights probably) in case power fails and not enough window light, as that helps mitigate the risks from power loss for any reason, not just poor selectivity on a fault. Might be easier and cheaper than the effort to split tails and insert a fused-switch for something of the order of 40A.

 

[Toonjabba]

Could someone please suggest where I can get a good priced 6-7 kw shower

 

[Mike Johnson]

I'v read through the thread and did not see any mention of RCD protection, IMO the CU in the shed should at least be supplied by an RCD from the main CU.

 

[DPG]

I'v read through the thread and did not see any mention of RCD protection, IMO the CU in the shed should at least be supplied by an RCD from the main CU.

Fair point. Although the SWA would be better fed from an MCB in the main board and then an RCD in the remote consumer unit?

 

[Mike Johnson]

Only if the MCB in the CU is already RCD protected. IMO

 

[DPG]

Only if the MCB in the CU is already RCD protected. IMO

Will the SWA need RCD protection in this case? I may need to re-read the thread.

 

[Deleted account]

I’m a little confused, actually a lot confused. Are we talking about the size of the final circuits or the size of SWA supplying the final circuits.

6mm was mentioned for a 7 kw shower. Fine for the final circuit, but I think the SWA should be higher considering the radial socket circuit that is being fitted.

as mentioned a heater, kettle hair dryer etc may and probably will be used on this radial.

so I’d say at least 10 mm for the SWA.