Stefek Zaba wrote:
Andy Wade wrote:
It's entirely INAPPROPRIATE to use that guideline to say 'how should
I size the cables and overcurrent protection for the cooker final
circuit'!
... No, for a *household* cooking appliance the "first 10 A plus 30%
of remainder" rule appears in both Tables 1A and 1B of the OSG.
Therefore it applies to *both* the design current of the cooker
circuit itself and to the loading presented to the installation.
Fairy neurf. For an entire cooking installation - hob + oven(s) - it
indeed seems entirely reasonable to me to consider the design load as
diversified, as you simply can't draw the flat-out load for any serious
length of time.

However, this case isn't one where the current is /limited/ to the
'design load' by the nature of the appliance.

So although, as Andy Wade showed, the "diversity" of a 5kW hob may only
be 13.6A, if the cable is protected by a 16A or 20A MCB, the design
current of the circuit then becomes the rating of the protective device.

IMHO.

Owain