Cables to run accross concrete floor

[sidekick]

I will have to get tails from meter more than 15m to consumer unit.
Will also gave to either 12m through concrete floor or through a double skin wall to a room with suspended floor for 10m and back 5m through concrete floor. Whats the best way to do and protect this within regs etc.

 

[Guest55]

tails will have to sub-fused down with switch unit to go that distance to the CU.
And you'd need rcd protection for the sub-mains if the tails arent in steel conduit.
SWA a better bet to be honest.

 

[sidekick]

Thanks. where could i put fused switch as i dont think allowed in meter cabinet on outside wall and next point of cable above floor is at csu

 

[Guitarist]

No room in outside cabinet?

 

[sidekick]

No room in outside cabinet?

depends on how or what used to terminate 25mm swa for merer tails to connect to. Also thought not allowed to add customer ware to meter board in cabinet.

 

[i=p/u]

switchfuse , rcd 25mm tails in in 32mm conduit in floor

 

[ringer]

Guys, I think the OP knows <b>what<\b> needs installing, he is asking for advice on <b>how<\b> to install it.
Swichfuses are not generally either small or nice to look at. And putting conduit in a concrete floor is not easy either. Then there is the challenge of pulling 25mm tails through the conduit. Swa is more flexible and therefore easier to run into and out of the ground and along an imperfectly chopped out channel in a concrete floor. I would look in to putting a steel cap over the channel rather than completely enclosing the swa in fresh concrete. As for the switch fuse, without seeing the current arrangements it is difficult to suggest a solution. Is it not possible to go through the wall to fit the switch fuse inside?

 

[sidekick]

switchfuse , rcd 25mm tails in in 32mm conduit in floor

Is that just 25mm tails in conduit to csu instead of 25mm swa

 

[rich.250]

I'd say, 50mm deep in floor for protection against screws and the like. If the same is done if it comes up a wall or surface. Then Rcd could be eliminated as discrimination may be an issue.
Personally I wouldn't use tails to do this run as it probably more expensive than swa, if you fuse if down could you not use 16mm??

 

[sidekick]

Could go through wall but new buil extension and refurb with customer not wanting anything on inside which is also one reason for moving consumer unit. Any ideas on best type/rcd switch fuse to use. was goi g to fit click switch fuse but not rcd'd.

 

[Farmelectrics]

Done similar job a while back we ran 25mm saw in channel and put cable in scaffold tube for extra protection on the instructions of the firm I was working for

 

[sidekick]

I'd say, 50mm deep in floor for protection against screws and the like. If the same is done if it comes up a wall or surface. Then Rcd could be eliminated as discrimination may be an issue.
Personally I wouldn't use tails to do this run as it probably more expensive than swa, if you fuse if down could you not use 16mm??

Yes but quite large property with family of three kids and growing demand on elec etc. would 16mm still be ok??

 

[rich.250]

Use swa, then can omit Rcd protection unless a TT.
If its not a TT I'd use a small metal CU with main switch and CB.

 

[sidekick]

Done similar job a while back we ran 25mm saw in channel and put cable in scaffold tube for extra protection on the instructions of the firm I was working for

What did you use for switch fuse?

 

[rich.250]

Depends on the loading. Like you say if they use a lot then maybe not. I would expect that the supply tails are 16mm?
If that's the case if say the DNO fuse is an 80A.