Advice on Consumer Unit Ampage

[irishsailor]

Can some one please explain:

For example you have an 8 way consumer unit 100A mains switch

but you have say 2 x 32A Ring, 1 x 40A shower, 2 X 6A lighting circuits, a 32A cooker and 16A immersion

How is all this calculated and what is the maximum load etc

Also does the 100A CU switch also have to be the same as the service head or could you have an 80A service head and 100A CU switch

Sorry if it is complicated

Irish

 

[old dog]

simple diversity example 32 amp mcb ring main will not be pulling 32amp at the same time as the shower and only
the kitchen ring will come close to full capacity.
as for 100amp cu with 80amp cpd no problem

hi try this atip i picked up years ago from an old spark add your breakers x 0.4
example the cu where i am now 2 bed flat 4x32 + 1x16 +3x6= 162
162x0.4=64.8 now do the calcs from the tables in the osg there nwont be mutch
in exept this way is faster