10mm tails

[gadget300]

I know that 25mm tails are the norm, but if the outgoing tails from the meter are in henley blocks, there is 1 main switch for the installation, the outgoing tails to a small board (2 way) are 10mm and less than 3 meters is this ok. The tails to the main board are 25mm by the way.

Have seen this before, but cant find a current reg in the 17th that specifically mentions this. Am i right in thinking that as the demand on the small db is approx 40 amps the 10mm should suffice.

 

[Darkwood]

If the current demand of the 2way cannot exceed the rating of the tails eg you have 2 x 20amp fuses and its not expandable with spare ways then its ok because the nature of the fuse rating limits the load on the tails.