Minimum rating for diversity?

[EFLImpudence]

Is there a minimum rating for using diversity?

As per another thread, for example, a 3kW @ 230V oven.

3000 / 230 = 13.043A so technically cannot use a plug.
(I know it would be better on its own circuit but for this argument isn't going to be.)

However applying diversity this is reduced to 10.91A

Is this acceptable bearing in mind that the oven may only have two elements?

 

[ricicle]

Also bear in mind that once the oven is at temperature the elements will be cycling so there will not be full load.
Although not good design from the outset, the 13.043A should not be a problem for the 1362 fuse in the plug. As for the plug/socket combination that's another discussion for how .043A over will affect them over their lifetimes with the small durations likely.

 

[ericmark]

I know boats with a B6 MCB feeding them could run a washing machine with a 2.2kW heater in it but this is not diversity.

Diversity only really kicks in with three or more items and we assume that all three will not demand max power together.

The cooker as a whole with in my case 9 items which can draw power. 4 hob areas and two elements in top oven and three in bottom oven can still be feed with a B32 MCB. However you can't double up on that and add the microwave running off the 13A socket on the cooker isolator.

 

[EFLImpudence]

Diversity only really kicks in with three or more items and we assume that all three will not demand max power together.

Yes, of course. Thanks.

 

[letinman]

the regs do say that
a circuit shall not be designed so that even a small overload is likely to be used for long periods

well an oven is not on for long periods really so even without diversity it is fine

 

[securespark]

Here's a link to a thread I posted in a while back.

I saw two hand dryers (@10A each, wired into 1 13A spur) and the opinion is that the fuse will take the load.

Not good, IMO, but it will take it. Does that scenario comply with the regs in terms of diversity, though?

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