Clarification Required

[Geps]

Hi,

Can someone just clarify a couple of points for me please....

Do ALL electrical points have to be accessible for inspection - including ELV/data ones?

Is there a generally accepted definition of 'accessible'?
eg Does it have to be visible? Can it be behind something that's easily/quickly removed? Can it be inside a lockable distribution board?

Thanks in advance,

 

[1john]

Could you be a little more specific?

 

[Geps]

I'll try....

I'm starting to look at ways to implement a home automation network which will use a mixture of 12VDC and data cables, as well as the usual 230VAC. I'm trying to work out what needs to be accessible..and how easily.

As I understand it when you have an electrical connection (ie via two cables joined in chocbox) you have to have it easily accessible for inspection.

Does it matter if you're only putting 12V though from a battery?

If you then run Cat5 cable for a network, and join two cables....it's only passing data and not power....so do the rules still apply?

I'll be running everything past an electrician before work commences but would like to get a few designs for the structured wiring clear in my head so I can start to get an idea of costings etc.


Not sure if that helps?

 

[1john]

If a join will be concealed it should be crimped or soldered, although with cat5 and smaller cables they are prob easier to solder. Surely if this is a new install then all runs of cable should be in one length of cable from point to point, thus all connections would be made in accessories.

 

[ban-all-sheds]

Does it matter if you're only putting 12V though from a battery?

AFAIK there's no exemption.

If you then run Cat5 cable for a network, and join two cables....it's only passing data and not power....so do the rules still apply?

Don't join network cables.

And don't use Cat5 - go for Cat 6 or 6a.

 

[Geps]

If a join will be concealed it should be crimped or soldered, although with cat5 and smaller cables they are prob easier to solder. Surely if this is a new install then all runs of cable should be in one length of cable from point to point, thus all connections would be made in accessories.

Ideally yeah but I'm trying to wire it in a way that means it can be reverted to a 'standard' wiring layout when I sell up so I won't need to rewire again. It's very complicated to be honest and I'm still working out the best way to do it myself.

 

[Geps]

Does it matter if you're only putting 12V though from a battery?

AFAIK there's no exemption.

If you then run Cat5 cable for a network, and join two cables....it's only passing data and not power....so do the rules still apply?

Don't join network cables.

And don't use Cat5 - go for Cat 6 or 6a.

I have to join the cables at some point - it's not a ethernet network it's a special network used for home automation that means you daisy chain the modules. Ideally I can put a ring around the top of the room and then drop down to the accessories. I was thinking it would save money and be more flexible than dropping it down to every accessory and back up again.



I'm right in assuming that lifting a floorboard isn't classed as easily accessible aren't I?

 

[1john]

No, under a floor is unaccessable. Why not put in conduit drops if you want to do weird stuff and then remove it, if what you are doing is a useful tihng then why remove it when you sell up?

 

[Geps]

Mainly because I want as little on show as possible..so it would really ruin the looks of it.

It's useful bu you need the time, patience and knowledge etc to maintain it....most people aren't interested in it so would be put off.

 

[Chri5]

Star wire all single data /signal cables back to a single point. Look at krone 237a strips in a BC 301. 100 pairs of terminations in a 12" x 7" box

The 237a strips hold 10 pairs, if you are just using the primary 2 pairs of a Cat 5/6/7 cable then simply terminate 5 cables per block, You can then patch the cables via krone 1 pair patch leads or jumper wire.

Where you need daisy chains then do that via the krone 237a with loops of cable/ jumper wire.

You then have situation where the cables could simply revert to network use in a future time.

The other alternative is to consider wireless systems, lighting, media, heating are all available as wireless mediums and I'm sure a common standard such as wifi might do the job.

As for your question about joins, don't have them and there's no access issue. Have them and they have the potential to fail hence why BS rules that access is required.

If you need more than 50 cables, 2 pairs connected bigger boxes are available,

As are rack mounted frames, large frames, pretty well much all sorts and they are standard BT / UK telecoms kit.

 

[Geps]

Thanks Chri5,

I was actually thinking though about connecting the mains cable between floors. Ideally I'd like to star wire single lights and then convert back to ring main when I sell.

 

[ban-all-sheds]

Lighting circuits are not wired as rings.

If you're installing a new lighting circuit from scratch there should be no need to introduce joints into it.