How many conductors allowed in the 100A breaker?

[jpadie]

I recall dimly there being a regulatory change on limiting conductors in mcbs to one only (not sure how a ring main would work then...).  Does this hold true for the main manual breaker in a CU?  

 

I'm adding a third RCD to a CU and can just about squeeze in 3 16mm2 cables to the main switch.  Before today there have always been two.   Is this allowed these days?   What's the usual solution if not (joining these thicker cables seems non-trivial).

 

 

[ProDave]

Making such alterations to a CU is usually frowned upon.  If you are going to do it the usual way (that the manufacturers do it) is one cable daisy chaining from one to the next so no more than 2 in one terminal.

 

Manufacturers tend to use fine cored cables for that, not the normal "meter tails"