New Consumer Unit and Diversity

[steve1811uk]

Planning the fitting of a new split load consumer unit. It's a 100A main 80A RCD type. On the 80A RCD side I plan to fit;

Shower 7.8 kW - 34A
Kitchen sockets 32A ring
Downstairs sockets 32A ring
Upstairs sockets 32A ring

Is this acceptable practice or not? I've been reading about diversity but don't know if I should apply that to the 80A RCD or not.

Applying the recommended values for Diversity would give 34 + 32 + 12.8 +12.8 = 91.6A

Or do I just use common sense and assess the total load at any one time as being less than 80A? and forget about applying diversity to the CU? I won't actually be putting a greater load on the supply, as the washing machine and tumble dryer are connected to the upstairs ring that drops down into the utility room. I'll just be adding the kitchen ring and moving those appliances onto that. Steve.

 

[davy_owen_88]

The diversity allowances are pretty ridiculous to be honest.

It's unlikely that you will use 32A over all the ring circuits in a standard house for more than a few minutes at a time let alone 57A+.

Common sense or a clamp meter on the tails will give a better idea of demand.

Davy

 

[sparkyspike]

If you stuck to diversity allowances, most houses would be 3 phase and electric showers would be impossible to install.