UK Double pole or Single pole + Neutral for domestic extension supply?

[Joemile]

I've been carrying out quite a few domestic extension first fixes recently which involves providing a power supply installed from the properties mains.

I have always just Henley blocked from the properties main consumer unit tails into a 63/80/100A BS-88 fuse Main switch board then from the board to a 25mm SWA that feeds the extensions consumer unit but I haven't considered that the main switch boards I have been installing only use Single pole + Neutral main switches.

I'm just wondering are these types of main switch boards okay for this type of installation or should I be using a double pole switch supply board?

 

[westward10]

That to me is very confusing but that could be me.

 

[Joemile]

That to me is very confusing but that could be me.

Sorry, I've re-written it so maybe it's a bit clearer?

 

[westward10]

What are you describing as a single-pole + neutral main switch.

 

[Joemile]

What are you describing as a single-pole + neutral main switch.

The fuseboard that powers and protects the SWA cable feeding the extensions fuseboard. The manufacturer description only states that it is single pole+neutral.

Here's an example: SF0100 - Fusebox 100A Fused Switch - https://thomased.co.uk/ProductDetails/?code=SF0100

 

[westward10]

The fuseboard that powers and protects the SWA cable feeding the extensions fuseboard. The manufacturer description only states that it is single pole+neutral.

Here's an example: SF0100 - Fusebox 100A Fused Switch - https://thomased.co.uk/ProductDetails/?code=SF0100

Yes it has a double-pole 60947-3 isolator but the distribution board is described as single-pole and neutral.

 

[Lucien Nunes]

In a CU or switchfuse description, SP+N means it has a line busbar for the MCBs / RCBOs but a neutral terminal bar. Before the use of RCDs and RCBOs, the SP made sense because all the protective devices were single-pole only, although for a single-phase application the main switch itself will be DP. The distinction has become a bit blurred now that so many SP+N boards are fitted with DP RCDs or SPSN RCBOs etc.

 

[Joemile]

In a CU or switchfuse description, SP+N means it has a line busbar for the MCBs / RCBOs but a neutral terminal bar. Before the use of RCDs and RCBOs, the SP made sense because all the protective devices were single-pole only, although for a single-phase application the main switch itself will be DP. The distinction has become a bit blurred now that so many SP+N boards are fitted with DP RCDs or SPSN RCBOs etc.

Thanks for the explanation, That's clears up the confusion then. I was worried that I'd been installing insufficient equipment!