hi al,
thanks for the reply.
it does state max 50A for both, but above that it says "A 30 or 32A circuit is usually appropriate for household or similar cookers of rating up to 15kW
ive attached the page for you
The key word to that particular section is "
cookers" which are one of a very few select categories that can have allowance made to their final ccts.
Demand & diversity is ordinarily not permitted to finals - only the mains & sub-mains supplying them.
They give recognition to this fact in the above section ^^^
Its a rare case indeed when we told we can attach a mid 50A load to a 30A protective device!
They`re telling us that a true "cooker" (combined oven/hob/grill) has an Ib significantly below its summed totals, & won`t be capable of supplying its rated max current for sustained periods - so its permitted to make allowance for this in the cct supplying it. This applies to the cable as well as the protective device.
You`ll note the choice of wording changes in the subsequent section - where they refer to
"cooking appliances" upto 50A. With these, much more thought is required before applying any demand & diversity. As in your case, a seperate hob & oven will work independantly from one another, & each should have their Ib`s assessed quite seperately. As i denoted, such an assessment would lead you to fairly assume certain thermostatic cycling for each of the devices & a modest derating of max current draw.
The two sections could have been written to make these factors more clearly understood - but the guts of the section is as i`ve described.
Hope that makes it clearer Flukey