mcb,s

[leon]

is it acceptable to run a ring main off a 20 amp mcb?
i ask this because i have a spare fuseway in the cu and was thinking about putting a seperate ring in the dining room.
it will only have 3 sockets one of which will be spurred to a security light.
there will be roughly 11 to 12 meters of cable used as the room itself is only about 4 square meters,so would a 20 amp mcb be sufficient ?

 

[mapj1]

It will be safe, if non-standard. Why not fit a 32A breaker into the box in that position and make a conventional ring, or leave it at 20A and do a radial ?

 

[leon]

i was thinking of a radial, but wouldnt a ring be better as the electrical current can flow from either end and raise the current carrying capacity of the circuit without increasing cable size or changing to a 32 amp mcb?

 

[mapj1]

The current capacity is needlessly limited by the MCB in this case. Not dangerous though.

 

[leon]

ok thanks, i,ll just stick with a radial and save a few bob on extra cable.

 

[andy]

ok thanks, i,ll just stick with a radial and save a few bob on extra cable.

how much do you plan to save?!

there will be roughly 11 to 12 meters of cable used