10mm2 to 3 x 2.5mm2 Connection

[mike2016]

I'm retiring an old electric shower that was fed by a 10mm2 power cable. I'll get an Electrician to replace the 40A consumer unit fuse with a 20A one. I want to run 3 x small 13A radial circuits from it into the attic in 2.5mm2 wire. 

My question is how best to join these up? I've a connector block big enough for 10mm2 and I can wire in 3 x 2.5mm2 cables in the other side but is there a more appropriate / safe method or connector block I should look at using for this task?

Thanks. 

[Mr Punter]

Would there be any mileage in leaving the existing 40A and having a small consumer unit for the new circuits?

 

A proper sparky like @ProDave will hopefully comment soon...

[Carrerahill]

19 minutes ago, mike2016 said:

I'm retiring an old electric shower that was fed by a 10mm2 power cable. I'll get an Electrician to replace the 40A consumer unit fuse with a 20A one. I want to run 3 x small 13A radial circuits from it into the attic in 2.5mm2 wire. 

My question is how best to join these up? I've a connector block big enough for 10mm2 and I can wire in 3 x 2.5mm2 cables in the other side but is there a more appropriate / safe method or connector block I should look at using for this task?

Thanks. 

I would use something like this: https://www.tlc-direct.co.uk/Products/AAJB60.html?source=adwords&ad_position=&ad_id=415703895075&placement=&kw=&network=u&matchtype=&ad_type=&product_id=AAJB60&product_partition_id=351476229327&campaign=shopping_accessories&version=finalurl_v3&gclid=CjwKCAjw8J32BRBCEiwApQEKgTIGSLdYjkmKXYLyip3tP_5YIhEwGaKbUjzy6NpqSTz6nxnVC1_GuBoCz80QAvD_BwE

 

You can cleanly terminate the 10mm into that and then your 3 No. 2.5mm (probably doubled over to increase size).

 

[ProDave]

That big terminal box from TLC is the only way I know of making that sort of connection.

[mike2016]

Cheers! Will have a look at getting one of those. It's too hard to run a replacement cable so will use the connector block temporarily and replace with that unit when it arrives. Much appreciated. 

[ProDave]

The alternative and possibly more useful solution is run a 2.5mm ring circuit from the end of your 10mm cable to several sockets and feed it from a 32A mcb.  This has earned the nickname of a "lollipop circuit"