A
Aok1
I would appreciate some advice on the following as i am not a full time spark and most of my electrical work is normally limited to minor works.
I was at a clients house in the week and while talking she mentioned that she needed to get a 3 phase supply installed at a cost of £6.5K + for her under floor heating which apparently draws 80A. The spark who done the re-wire in January thinks the total load is going to be around 135A which includes everything in the house.
He has said all the db's need changing to 3 phase.
There house is large but there are no electric showers, cooker is gas so the only items are really pull any current are on the ring and kitchen appliances.
I had a look quick look at the current system which has a 60A fuse on the incoming and then 2 x 12 way boards, 1 of which is for the underfloor 4 x 20a mcbs - Hall, living room, kitchen and small bathroom.
I think the figure of 135A is way out and no diversity has been allowed and there would be no need to change the db's either.
Would i be correct in thinking that no diversity is allowed for the underfloor heating but more common sense in that she has said that there would only ever be a maximum off 2 x areas on and never all 4.
I am due back on Friday to finish some AV and security stuff so i was thinking of advising possibly getting the 60A upgraded to 80A or 100A and also clamp testing the supply with the 2 x areas of the underfloor on and some other items to get some sort of idea on the actual load.
Thanks
I was at a clients house in the week and while talking she mentioned that she needed to get a 3 phase supply installed at a cost of £6.5K + for her under floor heating which apparently draws 80A. The spark who done the re-wire in January thinks the total load is going to be around 135A which includes everything in the house.
He has said all the db's need changing to 3 phase.
There house is large but there are no electric showers, cooker is gas so the only items are really pull any current are on the ring and kitchen appliances.
I had a look quick look at the current system which has a 60A fuse on the incoming and then 2 x 12 way boards, 1 of which is for the underfloor 4 x 20a mcbs - Hall, living room, kitchen and small bathroom.
I think the figure of 135A is way out and no diversity has been allowed and there would be no need to change the db's either.
Would i be correct in thinking that no diversity is allowed for the underfloor heating but more common sense in that she has said that there would only ever be a maximum off 2 x areas on and never all 4.
I am due back on Friday to finish some AV and security stuff so i was thinking of advising possibly getting the 60A upgraded to 80A or 100A and also clamp testing the supply with the 2 x areas of the underfloor on and some other items to get some sort of idea on the actual load.
Thanks
