new house 3phase heat pump

glasgospark · May 19, 2013

new house guys with a new heating system through mcs real scheme

3 phase supply run into house the pump is the only piece of equipment requiring 3phase ,

question is looking for best way to do this was thinking give the house itself the normal dual rcd db then from 3phase mains to lucy blocks fuse down for pump.

pump is situated in the same location as main cable head ,

4kw 32a 3phase supply required via rotary isolator

any views ?

guest119 · May 21, 2013

Why would it be a 100A switch? You can get 32A switchfuses. Socomec make them among others.

The clue is in your post........what size of fuses in the cut out???????????????????

johnboy6083 · May 22, 2013

Yes, but your only providing over current protection for the supply to the heat pump. As such, from the Henley block you take a 6mm2 for example to the switchfuse. The 32A fuses protect that cable from overload, the 100A fuses provide short circuit protection.

If you consider a busbar chamber, you wouldn't size everything fed from it to the size of the incomer.

guest119 · May 22, 2013

I give up.

Knobhead · May 22, 2013

johnboy6083 said:
You only require one point of isolation. This is primarily the cutout. I agree that one switch in front of everything is best, but only if the customer will pay!

Why would it be a 100A switch? You can get 32A switchfuses. Socomec make them among others.