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Hi all. I am a domestic electrician and I only work on houses. We do a lot of standard new builds.
Some of the new upcoming houses are said to have a 3 phase supply, I'm not entirely sure how this affects me, what do I need to do different, what fuseboard etc etc
Really appreciate any advice
Thank you
Longer term of course once there is a 3 phase supply in most houses it is likely that someone will want to use all 3 phases for something at some point, if only to fit 3 times as many not quite pre-notifiable solar panels, as the limit is 16a per phase, or a maybe larger car charger, where some 22kW ones are just the same current rating as the 7kW ones internally but with a contactor with a couple more poles. Then there are larger cookers that are easier to fit with 3 phases of 2,5mm2 rather than 6mm2 and a bent tin link that is clearly an afterthought for the UK export model. Mind you cooker isolators would need to catch up.
I think it is not a bad thing,
Personally I'd suggest a 3 phase box with single pole breakers in most of the ways is perfectly sensible, if not common in domestic right now. No need to have many rows of breakers.
An example 
-only one true 3 phase load with 3 pole linked breaker, the rest are single phase MCBs that could just as easily have been RCBOs /AFDs if you must. (I may have preferred to see sleeves on unused bus pins, but that is not the main point to make .)
Some folks assumptions about colours for 3 phase colour SWA re-used for single phase may need more careful checking before termination. black is not always the earth ;-) But as above, other places have been doing it for years without blinking, and I am sure we can join them.
Mike.
Longer term of course once there is a 3 phase supply in most houses it is likely that someone will want to use all 3 phases for something at some point, if only to fit 3 times as many not quite pre-notifiable solar panels, as the limit is 16a per phase, or a maybe larger car charger, where some 22kW ones are just the same current rating as the 7kW ones internally but with a contactor with a couple more poles. Then there are larger cookers that are easier to fit with 3 phases of 2,5mm2 rather than 6mm2 and a bent tin link that is clearly an afterthought for the UK export model. Mind you cooker isolators would need to catch up.
I think it is not a bad thing,
Personally I'd suggest a 3 phase box with single pole breakers in most of the ways is perfectly sensible, if not common in domestic right now. No need to have many rows of breakers.
An example
-only one true 3 phase load with 3 pole linked breaker, the rest are single phase MCBs that could just as easily have been RCBOs /AFDs if you must. (I may have preferred to see sleeves on unused bus pins, but that is not the main point to make .)
Some folks assumptions about colours for 3 phase colour SWA re-used for single phase may need more careful checking before termination. black is not always the earth ;-) But as above, other places have been doing it for years without blinking, and I am sure we can join them.
Mike.
