Earth and tails size???

[darren7]

Hello I have been looking at my CU. Well I looked and saw that the earth looked very small (TN-S) well it looks all ok at the service point where it comes in the the house, but then it is about half the size, where they have changed the CU in the past and moved it, they have joined it with like this really dodgy bolt looking thing that just is tucked up the back! bet you boys have seen this many times! The earth is a stranded cable as normal, but after the join it is tiny.

I have a 60 amp rated main fuse and there is an isolator fitted. house is late 50's

What I would like to do is change the earth at the join, I was going to get a new Henley block and do this, what size tails would you recommend.

 

[fido]

I would get 16mm for the main earth from the supply to the consumer unit. The standard size for live and neutral is 25mm but the main fuse is normally 100A. If the terminals in the consumer unit are big enough to take 25mm that would be the size to use.

 

[darren7]

Thank you,

Looking at the latest wylex split load cu, it says maximum size for fittings 16mm, it has a 100amp trip in this unit,

What I am saying is how do people get 25mm in units that take 16mm.


Many thanks

Darren

 

[pdcelec]

it has a 100amp trip in this unit,

The 100A main switch is NOT a trip. The 100A is the maximum amount of current that the switch will let through without causing it damage

 

[darren7]

Thank you Pdcelec.

So when people fit 25mm, they put terminals on the end of the tails, as there is quite a few ( new builds) running this.


Darren

 

[plugwash]

the incomer should be able to take 25mm, its generally the outgoing neutral and earth terminals that can't.