submain 10 mtrs away from main supply run in tails

[egginyourface]

Exactly what the title says. The tails have been run under the floor and chased inside a wall with no protection. What should i do?

Its a kitchen rewire and its nearly finished. Theres no switch fuse to isolate sub main only main cut out fuse

 

[Spudnik]

Sorry mate but im not sure i understand?

 

[egginyourface]

the main supply and meter box are outside at the front of house. from there the the meter tails are run under floor boards and chased into wall directly to consumer unit.

 

[Noton1205]

I would suggest installing new tails from the meter and install a switch fuse in the meter box. Then if you can, replace the tails that are chased in with 16mm t+e.

 

[egginyourface]

the thing is job is nearly done and dusted. What about a 100 milliamp rcd switched fuse?

 

[moondog]

Won't these tails need to be taken via a RCD in the meter enclosure before they enter the house,to afford protection to tails?

 

[Spudnik]

The tails will need RCD protection if they are buried in the wall.

Anyway cant you run them surface in trunking?

If not its either steel conduit or SWA.

 

[johnboy6083]

i wouldnt use twin and skin, unless you use an s type30mA rcd, or its 50mm below the surfaceor buried under earthed metal. SWA is a good alternative

 

[johnboy6083]

beat me to it jason!

 

[moondog]

Sorry ,a bit late,

 

[egginyourface]

whats a s type 30 milli amp rcd?

 

[Noton1205]

I didnt think tails had to be on an rcd? Best thing to do would be what jason said and use swa out of a switch fuse in the meter box. You do need a point of isolation between the meter and the consumer unit if the distance is more that 2M from the cutout.

 

[johnboy6083]

its a time delayed rcd. it is used to provide discrimination with RCD's, as the times 3 rule doesnt always work, according to the more experienced blokes on here.

 

[johnboy6083]

I didnt think tails had to be on an rcd? Best thing to do would be what jason said and use swa out of a switch fuse in the meter box. You do need a point of isolation between the meter and the consumer unit if the distance is more that 2M from the cutout.

they dont if theyre on the surface mate, but if theyre buried, and a dont comply with the 50mm rule, or protected by earthed metal, then an RCD is a viable alternative

agree with the over 3m rule

 

[egginyourface]

so s type 30 milliamp rcd

 

[Noton1205]

its a time delayed rcd. it is used to provide discrimination with RCD's, as the times 3 rule doesnt always work, according to the more experienced blokes on here.

Never seen an rcd installed before the cu on new installations. That massave site in canterbury has meters which feed 80a switch fuses. Out of those goes 16mm t+e which has runs in excess of 4 meters, but NO rcd fitted until youget to the cu.

 

[johnboy6083]

is it surface, ie on tray, in trunking, clipped ect? if so then that complies, if not then it doesnt

 

[egginyourface]

its chased in the wall and can very easily be damaged...

 

[Noton1205]

No protection john just run clipped to brick then plasterd over

 

[Des 56]

Fit a KMF switch fuse at the meter cabinet end and expose the buried tails
Then either surface trunking, or plate them with a suitable metal strap, otherwise you cant avoid having Rcd protection for the buried cables