Boxes for external SWA termination

[Robin]

What boxes are allowed/recommended for terminating SWA (2.5mm 3-core) on house/garage walls please?

I've only used SWA a few times and the last of those was so long ago I used IIRC metal boxes with gaskets. Now plastic seems to be the general rule - and what seems like expensive plastic to me. But I can't find in

the OSG etc a minimum IP rating. Is there one pl?

The garage wall is more exposed but I intend there to strip the armour and take the inner through the wall into the garage CU. So can I get away there with a lower IP rating?

[Archibald Tarquin Blenkinsopp]

I bought some plastic boxes from RS Electrical Birmingham, around £4-00 each. IP58

I think they are around 100mm square, they have screw positions within for DIN rail if needed.

I used a 20mm hole cutter for the cable gland, grounded the banjo using a separate earth, stripped off the armour and fed the inner through the garage wall to a similar box inside.

I mounted the boxes directly to the walls and drilled a 20mm hole at the rear of both boxes to allow the "inner" through.

I did consider taking the cable directly to the distribution board, but the two boxes were used so that in the event of any leakage, the repairs would be less of a problem.

The external box was applied to a generous layer of gripfill before being screwed up.

The same JB's were used for power and signals at various points elsewhere with no problem whatsoever.

Just had a look on the website, it seems they have dropped in price. Unbelievable!!

Regards

AB

[Tim Watts]

One of these, or one of its bigger friends will do nicely:

Beware of doing the earth "banjo" up though plastic - the plastic gives and may lead to poor pressure on the joint.

Pirana nuts are worth adding to the mix:

[harry]

Best to take the complete cable through the wall and terminate inside.

[Archibald Tarquin Blenkinsopp]

Not sure I agree with that. The protection that seems common looks a bit flimsy, either a boot expecting a 90 degree bend to the cable or a rubberry concertina device.

It seemed totally logical to me, to use a box to encase the 90 degree transition from ground to wall orifice.

Unless I,m missing the point completely, I would think that a cable brought directly in would not be a practical possibility at all.

AB

[ARW]

Or use

instead with the box you suggested.

[Roger Mills]

Why terminate the cable outside? Why not take it through the wall and terminate it inside? That's what I did. I mounted an aluminium bracket on the wall, close to the CU, with a big enough hole in it to take the SWA gland. The actual conductors then went straight into the CU. I used a piranha fitting to attach an earth wire so as to connect the armour to electrical ground.

[Robin]

Thanks to you and to the others who replied.

Looks like its the Wiska boxes - though they were the "expensive plastic" I'd hoped to avoid (as it's a job for an old woman who'll insist on paying me - and seeing the receipts for the "bits").

And the Piranha or Wiska clamp.

I'm not attracted to taking the cable through the wall because of the bend radius (min. 83mm). But I'm not that far from you (Roger) in that I'll take the inner into the CU so there'll be no electrical connection in the second box (other than the green/yellow single I'll probably run back from the CU so the armour is earthed at both ends).

ISTM that just leaves me to go to my grave ignorant of what minimum IP rating was actually required - along with much else of greater import of course :(

PS I'll have

on a tablet beside me: wish I'd had such a good guide as John Rumm's last time I used SWA.

[ARW]

So improvise. Terminate the SWA into a galvanized conduit end box (with lid) eg

drill a hole though the base of the end box and take the cores of the SWA into the garage through the hole into the garage.

Fill the box full of silicone.

[Capitol]

You don't have to take the cable in at a right angle, I normally have used 45 degrees, going through walls with SWA. That way, water falls down if any has penetrated..

[Roger Mills]

Indeed. And 3-core 2.5mm SWA cable is not that massive, so you can chip a bit of the brickwork away to accommodate the radius.

[In my case it wasn't a problem because my cable ran across the top of an alleyway door frame and straight into the garage with mo bends on the outside.]

[Roger Mills]

It probably doesn't matter too much in view of the fact that there won't be any electrical connections inside the box.

[Tim Watts]

Ooh yes - I had a vague idea something like that existed but could not find it when I looked!

[Robin]

Nice one, thanks. Made even better by the fact I've a couple of end boxes with lids in the attic that I couldn't bear to throw away.

[Robin]

My description was unclear: there will be connections in the box on the house where T&E comes through the wall. (And currently continues in white plastic conduit up the wall and, with gaps in it now, overhead into the garage. I've no chance of getting cable 3 or 3.5m up; and burial is out 'cos of the drains and access points in the way; so I'm just aiming to make it half decent.)

[John Rumm]

One trick I often use is to place a surface mounted external socket on a wall and use that as a handy place to terminate a swa - not always an appropriate to every situation but quite often handy. So the garage to shed feed at my place gains handy outside sockets at both ends, saves spare plastic boxes and does not need to fuss with difficult bends in the SWA ;-)

Yup, used the former many times. Not tried the latter, but they look good.

You may want to look at it from the other direction - i.e. look at what each level of IP protection offers, and decide which is appropriate for the circumstance you are installing in.

For example I have some external lantern style lamps on the top of a tall garden wall that are only something IP33, but in the circumstance is more than adequate protection for anything the weather could do to them... Although you could squirt a hose up one if you really wanted to!

It could do with some better photos probably - so if you take any, let us have them for the article. ;-)

[dennis]

I have been converting my lights to low voltage.

12V psu (2A DC) and LED side light bulbs in most of them. You can run 12 from a PSU.

I have removed the old bulb holder and crimped the bulb on after straightening the wires on the bases.

The crimps cost more than the bulbs.

They are quite bright but very white.

[ARW]

I'll let you into a secret. I knew exactly what they were and what they were called.

You posted this link

and it is the first item in "related items you may need".

It saved me from googling for a link to give to Robin:-)))))))