How would you route cables for this?

Associate
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Hi all,

Bit of a long shot but I'm baffled and struggling to work out how best to run the electric and AV cables if I were to wall mount my TV above the fireplace.

Obviously I'm thinking a fused outlet behind the TV and the easiest option would be to spur from the double socket to the bottom right hand side of the fireplace (see picture), however, I already have a switch spurred from this outlet for the bulbs to the niches. Ideally I don't want to have two spurs from one socket and therefore the only other option I have is to spur from the only other double socket on the left hand wall which would mean running power within an internal corner.

I also need to run audio/visual down by the right hand side socket as well.

So yeah, a bit of a mish mash and by no means simple.

Can I ask for some advice? How would you run the cables? What would be the easiest and safest route?

https://ibb.co/mhrDAG
https://ibb.co/nLrrxw

Adam
 
Caporegime
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Personally I would do this.

Where you have the light switch next to the double socket I would swap that for a switched FCU ringed into the double socket, then take the lights from the switched FCU.

You can then take a single spur (from the ring) up to a fused outlet behind the TV.

Your AV cabling just gets put into conduit chased into the wall, running down to where you want it to come out, you can either put sockets behind the TV, and or AV racking, to make it look neat and tidy, or just have the cables pop out of the wall conduit into the TV, and or racking, shelving, or where ever you are putting your AV system.
 
Associate
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Thanks mate.

I've chased cables before but I'm not 100% on the electric side of things. Forgive my ignorance but do you mean fit a FCU for the lights spurred from the double socket and then a second FCU spurred from the first FCU, to the TV?

I may have it totally wrong but thanks for your help anyway :)
 
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Thanks bremen.

Yeah I've read up about all that, it's just ensuring that I'm wiring each socket correctly and only taking spurs where I need them that I need be 100% sure on.

It may be a job for a sparky but if I can do it myself I'd prefer to.
 
Soldato
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What Entia suggested seems reasonable.

You loose the existing spur by incorporating the switch/fcu for the lights into the ring.

R6Bd6Xv.png

You're then free to run your single spur.
 
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Spoke with an electrician today and was told I'd need a fuse box upgrade because I'd need RCD protection... For one cable run due to me having to run it out of the safe zone and around the fireplace, also because I can't go more than 16mm deep on horizontal runs. Seems ridiculous.

Surely I could run a vertical channel from where the TV will go, remove the mantlepiece and then have cables coming out of the wall, run them within the mantlepiece externally to low level and then back in the wall within the safe zone in line with low level socket or skirting level?

Any suggestions appreciated.
 
Soldato
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Wouldn't something like this keep the cable with the correct zones (not 100% sure)?

I think the RCD requirement will be because you're adding to the circuit and testing requirements not because of zones.

AQfI3SR.png
 
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Yeah I was thinking along those lines too (literally :p).

Hmm, my existing ring has rcd protection anyway so not sure why he was mentioning a fuse box upgrade. Just don't want to get fleeced.
 
Caporegime
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RCD protection is because the cables are not buried 50mm or more into the wall, or you are not using cables having an earthed metallic covering or cables enclosed in an earthed metal conduit whether they are in safe zones or not.

Not having seen your fusebox, I could be wrong, but are you maybe getting MCB and RCD mixed up ?

Most concumer units have Mini Circuit Breakers (MCB) on the ring main, not RCD. (Residual Current Device)

You would have an RCD on the mains into the fusebox but not many have them on individual circuits.
 
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RCD protection is because the cables are not buried 50mm or more into the wall, or you are not using cables having an earthed metallic covering or cables enclosed in an earthed metal conduit whether they are in safe zones or not.

Not having seen your fusebox, I could be wrong, but are you maybe getting MCB and RCD mixed up ?

Most concumer units have Mini Circuit Breakers (MCB) on the ring main, not RCD. (Residual Current Device)

You would have an RCD on the mains into the fusebox but not many have them on individual circuits.

Ahh perhaps I am yeah... Great.

So what I thought was a simple job is turning out to be an absolute ballache. My walls are dot and dab so I have very little to play with in terms of chase depths. And as I need horizontal runs AFAIA, I cannot chase more than 16mm depth. Out of interest Entai, would bremen's suggestion above for routing work in terms of compliance do you know?
 
Caporegime
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When people talk about chasing the walls for cabling, you do actually chase the walls, as in cut into the brickwork or block work and create a channel to run the conduit or cables through, not just cut through the plasterboard and run the cables in the gap between the wall and plasterboard.

You then skim over the channel sealing the conduit in and finish the plasterboard over the final surface, so that the cables are 50mm or more below the final finished plasterboard surface.

Yes it creates a lot of mess and dust but that is the correct way to do things, if you are running cables outside of the regulatory safe zones.


Bremen's pic is not showing a good safe zone as it is showing the routing doing a 90° turn in the middle of a wall.

There are a number of electrical wiring safe zones in which the cables should run:
  1. Top of the wall – where the wall meets the ceiling there is a 150mm zone where cables should be run. It is at the top of the wall and runs horizontally around the whole wall
  2. The join between two walls – where one wall meets another, there is a safety zone on each wall for 150mm from the corner. This is the case if the angle where the walls meet is acute, as in the corner of a room, or obtuse as you would find on the edge of a chimney breast. These zones will always run vertically down the corner
  3. Horizontally from any switch or socket – The zone runs horizontally from both sides of the socket or switch until it reaches a corner or an obstacle such as a door
  4. Vertically from any switch or socket – the safety zone runs the width of the socket or switch both up to the ceiling and down to the floor
Easier to see here all the green areas are safe zones, other areas are not.

d2vHt8q.jpg

So to clarify,

A cable concealed in a wall or partition must

a) be at least 50mm from the surface [note 1]

b) have earthed armouring or an earthed metal sheath (eg SWA, a BS 8436 cable or MICC cable)

c) be enclosed in earthed steel conduit or trunking

d) be provided with mechanical protection (3mm steel is deemed sufficient to meet this requirement)

OR

e) be installed in a safe zone.

The 17th edition also requires cables in the safe zone to have 30mA RCD protection if not installed as per a, b, c or d.

Note 1 - If the wall or partition is made from, or partially made from metal, then the cable will require RCD protection or be installed as b), c) or d) above.
 
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Doubt it because I have coving there and that'd be a huge job. Would then need re-plastering I would think, instead of just being able to fill over the channel. Not entirely sure. Here is a photo of the consumer unit:-

https://ibb.co/iJULc6
 
Soldato
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Definitely no RCD in there.

Sorry I just looked on my PC rather than on my phone and you do have a RCD. It has RCD writen on it.
 
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Associate
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Yeah 30mA rings a bell. Sounds expensive, all for a bloody wall mounted TV.

Surely others have experienced this problem :(

Rules and regulations these days eh...
 
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