Diversity and maximum demand confusion!

[fry80657]

Can someone please explain the diversity maximum demand topic, it really confuses me! For instance in most properties I wire I have 9kw boiler 45A, 6kw cooker 32A, sockets 32 A x2, Lights 6A, Smoke Alarm 6A. What would be the maximum demand on this?

Thank you, appreciate the help.

 

[pushrod]

Not sure about the other circuits but for a cooker radial it is the first 10 amps plus 30% of the rest plus another 5A if there is a socket outlet in the control unit. Think lighting is 66% , but the consumer unit must be able to take the total without diversity being applied

 

[Guest123]

Hey.

Maximum demand is calculated as follows.

Lighting - 66% of the total current demand i.e add up all the lamps on your circuit and take 66% of that number.

Power - 100% of first ring circuit i.e 32A + 40% of all of all other ring circuits

Cooker - first 10A + 30% of the full load of the appliance over 10A + 5A if there is a socket outlet on the control unit.

If it's an instantaneous boiler then assume 100% demand,
also if its thermostatically controlled then there is no diversity allowable so you assume the current rating of the appliance

Shower - no diversity allowable

Hope this makes sense.

 

[ezzzekiel]

60 ish amps?

 

[WarrenG]

Hi fry80657,

There is a full breakdown in table 1B onsite Guide, p97.

Warren

 

[DanBrown]

As far as im aware, the maximum demand is the total amperage of all circuits after diversity has been taken into account.
Hope this helps...