conduit question

[Fred]

Hello,

I would like to run some flex from a conduit box to a PIR lantern. I was going to use flex for the last few inches rather than T&E because in theory the lantern could be moved; however in practice, once set to point at the ground rather than my neighbours' houses, it should remain in that position for ever. Does this mean T&E could be used?

My question is, what would I use to terminal the conduit? Surely I would need some sort of gland to keep the rain out? I can see male and female ends to screw onto other accessories but I can't find anything to use with a flex outlet. Can you help?

Merry Christmas!

[Dave Osborne]

If it's a conduit box like this:

you need one of these:

short (2") length of conduit,

and a gland like this:

gland will screw directly into the female adapter.

Alternatively, you can maybe do away with the conduit box and just use the female adapter and the gland on the end of the main conduit run.

[John]

Not many are so considerate as to not shine their lights into neighbour's houses. Some light to light up the air!

[Bill]

In message , Dave Osborne writes

this one will screw straight into the box

[Tim W]

Dave Osborne wibbled on Sunday 20 December 2009 16:02

WRT to the last point - I did exactly that for the entry for BT's wire from the pole.

Downward facing conduit, and gland/adpator solvent welded on as Dave said. Keeps the bugs out. Looks very neat too.

I included a BESA box (round conduit box further up, just in case BT (or me) needed to splice the cable.

[Fred]

Thanks. That's the bit of information I was missing: I didn't realise the gland screwed into the female adapter, I was looking for something that fitted directly to the box or conduit.

BTW are the boxes IP rated?

TIA

[Andy Dingley]

I believe not officially (as that would require testing, which can't be done as they're sold as components).

In practical terms, there's an optional rubber lid gasket. If you use those, they're "weatherproof" for our purposes. Also remember that they're sold without any lids or lid screws, and these are a separate part, ordered separately. When joining boxes or adapters to plastic conduit outside, use plumber's PVC cement.

Cheapest source (IMHE) is Discount Electrical, who have a wider range of bits & pieces too. I particularly like the single-side conduit clamps, if you're running conduit in a corner. Their tees & elbows also look neater when installed (rounded clip-on lids, not flat screwed ones) but are probably more awkward if you're regularly opening them up.

[Andrew Gabriel]

Conduit, even if waterproof, is liable to form condensation inside, and the design of the conduit system should allow for this to drain out.

[Fred]

What are the rules for this? Should there be a drain point every so many metres? Do I need to run the conduit slightly less than horizontal so that any condensation runs in a particular direction? Is it just a matter of leaving a tee piece with an open end to let the water out?

[Andrew Gabriel]

TBH, I don't think most people bother. I drill small drain holes in lowest parts. Also, in BESA boxes (and other outdoor accessories), I always think to myself "what's going to happen if a drip of water runs in on the outside of this wire?" This means I usually make a drip loop in the wire, and then position the connections nearer the top of the enclosure, away from any drips.

This isn't much of an issue in a heated building such as a house, but it's more significant outdoors, and in conduit which runs from indoors to outdoors. This was brough home to me some years ago when I worked in a building which had a length of conduit running up the outside wall from our ground floor ceiling to an outside light (no longer working). Every morning except in hot summer, water dripped out of the rusted BESA box on the ceiling over my desk, which was the condensation from the long vertical run outside.

[Fred]

Thanks, so it truly is a DIY solution! I wasn't sure whether there was some special attachment to be used.

And drill a small hole in the bottom of the box to let the drips out?

What do you do if there is a vertical drop into a light switch or socket? Use drip loops again?

I was going to use it outdoors and perhaps join T&E to flex (to a PIR) inside a box. I'll have to make sure I put the connections at the top like you suggest; perhaps I should even wrap them in amalgamating tape?

Thanks again.