A question about trunking

[PaulP59D]

Hi,

I posted a question earlier about connecting SWA using a gland and now I have another question on a related issue.

I have just erected a largish log cabin in my garden and since it's made of pine (or some other Scandinavian wood) which is thick enough not to need lining inside, I am wondering how best to hide the internal wiring.

As I see it I have two options (since I don't want sockets in the floor) and that is I either go for white dado-style trunking, or else I could get a router out (to shape the lid) and make some wooden trunking that would do the same job, but blend in more with the interior. By trunking I am talking about something that I could use to carry the cable in, as well as set the pattresses in for the wall sockets.

Are there any regulations that would forbid trunking being made from wood? Obviously I am thinking about fire hazard in the event of some kind of electrical failure?

 

[RF Lighting]

Richard burbridge used to make wooden trunking (and probably still do)
I fitted a few lengths of this a few years back, so I guess it is acceptable.
I can't see any real fire hazard as long as all accesories (if flush mounted) have earthed steel back boxes.

 

[plugwash]

cables get run through (think joist holes) and clipped to wood all the time, if doing so was a fire risk everyone would know about it by now.

the one thing i would say though is make sure its clear to anyone who might do diy in the building that the stuff is carrying cables (this applies just as much to commercial wooden trunking).

 

[PaulP59D]

Thanks chaps, wonderful advice again. Richard Burbridge, if I remember rightly, do stairs and the like, so wooden trunking might well be up their street. I had previously tried a general search for wooden trunking on google and didn't turn up much, but now I shall go and find their web site.

 

[ban-all-sheds]

 

[Pensdown]

It's a shame this is a DIY project, I think a nice surface MICC installation would look great in log cabin, personal choice of course.

 

[plugwash]

just how hard is MICC to terminate anyway? it certainly doesn't look any harder than SWA. you would need to get hold of the tooling though which may be a bit expensive though.

 

[Pensdown]

It's a bit trickier than SWA and you also need an insulation tester to make sure it's all OK before you start and again before you seal up the ends. Most sparks only use the pot crimping tool but if you were learning you would probably start with a stripping tool as apposed to a home made stripping bar.

Once you've done a few ends it's straight forward enough and well within the grasp of any practical person who can lay their hands on an insulation tester.

 

[Adam_151]

just how hard is MICC to terminate anyway? it certainly doesn't look any harder than SWA. you would need to get hold of the tooling though which may be a bit expensive though.

I don't think its that hard, a mate of mine didn't find it too hard when he did it at college, he is doing an engineering apprenticeship which for some reason has an electrical installation module.

...but I'd have thought that an IR test is much more inportant on MICC than it is on PVC, and thats another bit of kit that you'd need, I don't think the tools to do the actual terminating are massivly expensive in themselves, but IR testers are fairly costly

 

[Pensdown]

...but I'd have thought that an IR test is much more inportant on MICC than it is on PVC,

Very much so. When you buy MICC unless the ends have been properly sealed damp can get into the insulation. You normally strip about 150mm back on both ends and then IR test it. If it's clear then you can start terminating. If it's not then you have keep stripping it back until it is clear. You can normally tell if it’s damp because the insulation tends to fall off in lumps as opposed to powder.

When you screw the pot on you sometimes get a slither of copper as thick as a hair which can rap its self around the cores. Because it’s so thin it only shows up on the IR test before the pot is sealed.

You don’t need a fancy IR tester, on old wind up one will do.

 

[Lectrician]

I assume when we are talking trunking here, we are talking trunking PVC/PVC cables - not single insulated

MI is not too hard to use, aslong as your stripping tool is sharp, and you have not let the MI work harden has you installed it.

Getting your measurements exact is important. Don't get grease from your fingers in the non-setting compound. Meggar before sealing the pot with the potting tool.