100A crossover, Q regarding switching of 2 supplies

[C8XY]

Hi Guys,

I have an installation which has two incoming supplies.

1. General supply, billed to owner (Phase 1)
2. Off peak supply, shared between residents (Phase 2)

The old installation was very old, the fuse panel was in the hall outside the flat and was a large enclosure (2m x 0.5m) and was a complete mess. Most importantly there was no single means of isolation!
The off peak supply was for the under floor heating, which only came on at night so completely pointless! But in order to meet the managing agents requirements, we must reinstate the under floor heating back on to the off peak supply, but we also want it on during the day.
My solution:
Have a fuseboard for all under floor heating circuits, fed from a crossover relay/contactor which would be controlled via a timeclock.
My questions:

1. Where can I get the materials required for this?
2. What is the best way to isolate both supplies?

Thanks for your time reading this and I hope to get some answers!

Thanks, Rob.

 

[davelerave]

assuming it's tn-c-s and i understand your question


you need 2 pole switching to isolate both incoming phases

and suitable changeover to boost the heating load

a slightly unusual metering arrangement i think- single phase dual -tarriff would be simpler

 

[C8XY]

assuming it's tn-c-s and i understand your question


you need 2 pole switching to isolate both incoming phases

and suitable changeover to boost the heating load

a slightly unusual metering arrangement i think- single phase dual -tarriff would be simpler

I know i need double pole isolation, presumably this should be in the old fuse panel to individually isolate each supply, but in the flat by the new fuseboards, would i need to take the two feeds in to a 4 pole isolator so we have one single means of isolation within the property?

I know the metering is unusual but its a large apartment block in central london and the electrics are much older than me! We cant change how its metered unfortunately.

As for the switchover, I need 2 contactors, inversely linked that switch between the two supplies.
Wholesalers have no idea what I’m on about, hopefully some of you do

 

[Tester Steve]

Something like economy 7 switching??

Steve.