Overall Diversity in huge commercial kitchen

I do not think that there is a simple answer to this, it depends on the type of appliances and the expected pattern of use.

A total supply of 315 amps strongly suggests three phase as single phase supplies that big are rare. Is the connected load 300 amps per phase, or 300 amps single phase. An induction cook top often has a similar loading to radiant rings, but the AVERAGE  of several induction cookers will tend to be less as they heat so quickly and therefore run for a shorter time.

A fast food takeaway could if busy have numerous heavy loading appliances in almost continuous use, in which case allowing 75% of the connected load might be prudent.

A table service restaurant with each meal cooked to order might have a more moderate actual loading. Consider as an example, table 6 order four main meals of say steaks and vegetables. The peak loading of a grill and say six boiling rings can be considerable, but is unlikely to be continuous.

The next table might not order for some minutes. And even if a coach party arrive, are there enough waiters to take two dozen meal orders at once, and enough cooks to prepare many meals at the same time. Probably not, in which case allowing say 50% of the connected load should be ample.

Thanks

Its obviously not an easy and simple answer...I know this

That is why I laid it out to a community of engineers & technically capable people who may have enountered similar situations in the past

I just digged into the on site guide diversity tables and although there is no similar example in there, i found one that is for a small hotel kitchen which uses 100% of the biggest load + 80% of the second biggest + 60% of the rest

Using this rule the 300A were diversified to 200A approx which is 67% diversity

Cheers

What else of the rest of the load can be cut back at peak times - is heating gas or electric, if electric can it be time shifted - once the place is full it may not need so much. What are the 'mechanical' loads? Is their air con/ extraction running - all that 200kW of mostly heat (300A per phase right ?) has to get out of the kitchen somehow .Is there heat recovery ?

If nothing else the  leccy bill will focus attention on not leaving things running if not needed.

I suspect it will be OK actually but no-one's estimate will be particularly correct.

Mike

My feeling is that you need to ask a chef rather than an engineer.

The fridges and freezers will be switched on 24/7, but the compressors will be cycling on and off so some diversity there. The exact amount would depend upon the insulation, how often the doors are opened, etc.

The kitchen will be busy with prep when the place is closed, so low usage then front of house. Food mixers will be used intermittently and presumably mainly during prep. Microwaves will be intermittent.

Some services may be busier than others. The chefs will not be standing idle, but some of the appliances will some of the time.

It's not as if the whole place will be heavily loaded for a prolonged period - I would expect that the peak of activity would not be more than 2 hours - 19:30 to 21:30.

I presume this is a new design. Otherwise you can see by installing a temporary data logger and get the full view. Normally 66% diversity on this kind of load is a generous figure, because of the way equipment is actually used. For example one would expect an oven to be heated once and then left at temperature during service, and pot heating used intermittently. Grills will only be on some of the time etc. I assume this is spread across a 3ph 100A supply, so a little juggling to get a reasonable spread should be quite adequate.