Main Fuse

[s6stu]

Hi people,

I recently issued a cert with a maximum demand calculation of around 80A for a 60A main fuse. Although the fuse will last well over 10'000 hours at 80A, according to regs, at what point do you decide on upgrading the fuse? I also assume the elec board would have to be notified to carry out the work.

Just would like to know before/if the situation arises.

 

[Shakey]

Just wondering how you came about the figure of 80A as the maxumum demand?

have you applied diversity?

if it is a genuine 80A then by rights you have 'designed' an overload situation into the installation, and it should be upgraded anyway

I always state my maxumum demand as the main fuse size, because you should never have a stituation where the maximum demand is higher than the fuse!

 

[s6stu]

This was on a cu change and diversity has been applied