3rd Amendment EIC form question

[newtothis]

You could use something like this https://www.connexbox.com/dre-5-din-rail-enclosure.html

That looks ideal - I'll check all the circuits to confirm adding 3meters won't require any cable upgrading.
I really appreciate the input into moving the CU, I will keep yous informed, on the progress

 

[Richard Burns]

The 3m limit is a mixture of effects from the DNOs and the wiring regulations, the DNO fuse is not intended to provide protection to the CU tails so therefore you are omitting protection and the wiring regulations state that omission of protection at the origin can be done if the DNO allows it, the DNOs generally state 3m (though they can state otherwise) and there is another section under omission of protection that says if it is protected from the likelihood of damage then up to 3m is OK to omit protection.

Overall it works out that if it is less than 3m no protection is necessary, if above 3m it is better to provide protection.

If you are moving the CU above the door and chasing in the tails <50mm in the wall then 30mA RCD protection comes into play and this cannot be done without breaking the division of circuits to prevent nuisance tripping. Try and avoid this if you can.

 

[newtothis]

If you are moving the CU above the door and chasing in the tails <50mm in the wall then 30mA RCD protection comes into play and this cannot be done without breaking the division of circuits to prevent nuisance tripping. Try and avoid this if you can.

I'm going the 'wear the trousers' on this and put it in a nice accessible postion, about 30cm off the ground with plenty of room around it, not top of the door like the wife said. Richard, what do you mean by breaking the division of circuits ?

 

[Richard Burns]

30 cm off the ground? you'll trip over it!

The division of circuits is section 314, avoid danger and nuisance, ensure no fault on one circuit will affect another circuit.
With a single RCD at the origin protecting all the installation a minor transient earth fault in, say, an outside light will take out the whole house supply, not convenient in general.