Isolation and switching

[chris day]

I have a question regarding isolation and switching arrangements.

I want to work out what would work best within the regulations regarding splitting a new 200a TPN PME supply to serve flats above and a shop below.

my initial thinking new 200a PME supply - Trunking above feeding a new ryefield giving me x2 100a 3 phase supplies. (2x100a 3 phase supplies)
I would then have a x2 100a un- fused isolators for the shop and flats

*will i need an isolator between the Ryefield and the service head
*does the above sound feasible?

 

[The Ghost]

How many flats?

 

[chris day]

there is already a Ryefield up stream with x4 45a S-Phase supplies for each flat respectively

 

[Spoon]

Is this to do with your previous post.?

i have been asked to quote for a new supply to x4 new build flats and a commercial unit below

Supply from a PME service head - https://www.electriciansforums.co.uk/threads/supply-from-a-pme-service-head.171846/

 

[buzzlightyear]

there is already a Ryefield up stream with x4 45a S-Phase supplies for each flat respectively

not three phase then ,you need to up grade the s/phase to 3phase cause of loading ,speak to you client and let them speak to the DNO .

 

[Nebu1a]

Sounds like you are being the BNO. UK power networks have a good guide on this as I have been in a similar situation. Make sure you are in contact with the DNO and what their requirements are. Some DNOs may ask for a 3 phase isolator before the ryefield. If its a small install you may get away without one. I fitted switch fuses to my risers.

 

[Nebu1a]

Sorry missed the bit about the second ryefield