by BLAKEY1963 »
Sat Aug 04, 2007 7:47 pm
[quote="petec"]Hi, going to have a new kitchen fitted and the appliances changed, but I am a bit confused. To date I have had two installers out to give me a quote. The old hob has a 10m cable feeding it from the consumer box on a 32 mcb.
The ceramic hob is 6.5kw and the new double oven is 5.3kw. One installer said it would be ok to split this supply for the hob and double oven, but the other said that it would draw too much current with both appliances running and therefore I need a new 6m cable for the oven from the consumer box.
Due to costs, I may install the kitchen myself, but this issue with the supply has got me confused? any thoughts[/quote]
PETEC
SEE DOC S PROJECTS ON PART P , WORK IN KITCHEN IS NOTIFIABLE, SO U WILL HAVE TO A REGISTERED ELECTRICIAN IN
TO DO THE WORK.
TO GIVE U SOME INFO ON LOADING. 6.5 PLUS 5.3 = 11.8 KW.
DIVIDE 11800 WATTS BY 230 = 51 AMPS.
YOUR 10 MM2 IS RATED AT 63 AMPS IF CLIPPED DIRECT TO SURFACE.
PROBLEM IS DUE TO INSTALLATION METHODS USED IN HOUSE YOUR
CABLE WOULD BE DERATED TO 43 AMPS , WHICH SOUNDS FINE
WHEN DIVERSITY IS CONSIDERED ( NOT ALL OF THE 51 AMPS WOULD
BE USED ALL THE TIME.
HOWEVER IT IS STILL POSSIBLE TO PULL 51 AMP THROUGH CABLE
AND THIS WOULD OVER HEAT CABLE EVENTUALLY AND PROTECTIVE
DEVICE IF A 40 A MCB WOULD NOT COPE EITHER.
I WOULD PERSONALLY KEEP 6.5 KW HOB ON 10 MM2 CABLE AND
RATE MCB TO A 30 AMP.
AND YES U KNEW I WAS GOING TO SAY IT , I WOULD INSTALL A NEW CIRCUIT IN 6 MM2 FOR THE 5.3KW OVEN AND RATE MCB TO 30 AMP.
IT WOULD B THE SAFEST OPTION , OKAY EXTRA COST INITIALY BUT
IT WOULD DONE THE RIGHT WAY
BLAKEY1963