Advice on Installing Brick Lights

[pc1966]

Not sure the ground is waterlogged there. Also if it is going in proper outdoor duct then they might as well got for an easier cable to terminate!

 

[Midwest]

Not sure the ground is waterlogged there. Also if it is going in proper outdoor duct then they might as well got for an easier cable to terminate!

Might be after yesterdays storm. I much prefer to install swa in ducting, some nice twin wall.

 

[rjdainty1]

Thanks again all, especially the lengthy post from @pc1966 - thanks.

So following the additional advice, I'm now planning on:

• 25m x 3-core 1.5mm2 armoured cable
• 4 x Exterior Gland Kits
• Enclosure for inside garage

The point about having never done this before - you're quite right. I've just watched a good YouTube video explaining the gland fitting which helped a lot. Every day is a school day with my patio I'm finding.

I'll leave ducting but I'll be sure to bury at least 0.60m.

 

[pc1966]

The enclosure you link to is rather small. You seem to be fitting 4 lights, so will need 5 entry points, one for the main power and the 4*SWA. It would seem more sensible to look at a box that can take 4 SWA glands in a row at the bottom, etc. Many such boxes have knock-outs for 20mm (most common gland size, etc) but if you need to make 20mm holes than the Armeg "acceler8" hole saw does a great job on metal and plastic.

You also need to allow for some joints inside there but 5-way Wago leaver terminals are your friend. Also some ring tags and matching screws to attach to the "banjo" of the SWA gland.

Wago also do a box with a fancy plate to joining up (two, I think) SWA glands but I have never used one.

 

[davesparks]

• 25m x 3-core 1.5mm2 armoured cable
• 4 x Exterior Gland Kits
• Enclosure for inside garage

That enclosure wouldn't be my first choice.

Unless I have a very good reason not to I would always terminate armoured into a metal box. For that number of cables I'd likely go with a 6" adaptable box.
Metal boxes make the earthing connections easier, and tend not to bend so easily when the cable pulls against them.

The other thing missing from the list is an electrician to do the job safely and in compliance with the wiring regulations.

 

[Markyd]

I take it this is a new circuit and if so needs an EIC and notification to Building control

 

[suffolkspark]

Noticed a couple of guys suggesting NYY-J and HO7RNF are suitable for direct burial in this thread ? it's great cable but that's not the case.

Also you mention about needing to declare this work if you sell your house, which is true, but you'll need it tested and certified in any case so why dont you just get an electrician to do this whole job properly?

 

[rjdainty1]

Hello again all,

Okay, following multiple revisions - I'm hoping the list below takes into account the advice most have given:

• 25m x 1.5mm2 3-core SWA
• 25m x 150mm Warning Tile
• 1 x Wiska Box
• 3 x 5-way Wago
• 4 x Gland Kits

Thanks again

 

[rjdainty1]

Morning all,

So installation of the lights has gone pretty well, I went with the kit in my last post. The cable is laid, I’m just about to fill in the trench (I haven’t wired it all into the garage yet but I’ve tested that each light works okay).

I followed a video in how to install SWA cable with the glands, but it wasn’t until I was thinking last night that I realised those connections won’t be water tight. The plastic shroud fits snuggly on the cable, but it doesn’t make a tight connection with the back of the light - which means water could go through the connector into the light. I probably should have noticed this earlier but was too busy following the tutorial video.

I wouldn’t be comfortable leaving the cables so exposed so does anyone have any sealant they’d recommend? This will of course be buried under a shallow layer of soil, and given my choices of kit so far, I thought it best to post on here to ask.

Thanks

 

[pc1966]

Ah, following your link shows you got the indoor glands. This is what you ought to have got:

CW 20mm SWA Gland Pack - 3 Part External - 2 Glands

For the indoor garage supply part you can still use them as the armour has to be earthed to the source of power.

However, for the outdoor end you could use IP68 plastic glands for the SWA as you have 3-core so one core would also be the CPC (earth, in addition to the outer armour), and the other cores L & N. Remember to sleeve the conductors to show what they are used for, so green/yellow on the CPC, and blue sleeving on the neutral.

A quick search shows there as probably OK for that cable diameter:

https://www.NoLinkingToThis/p/tower-male-comp-gland-20mm-2-pack/45943

Note most glands do not seal very well except under ideal conditions, so before you put glands on the lights or junction some silicone sealant is a good idea. Unfortunately the sort you typically get for bathrooms, etc, gives off acetic acid as it cures (the vinegar smell) but you can get some that are intended for non-corrosive situations:

RS PRO White Sealant Paste 310 ml Cartridge | RS

uk.rs-online.com

If you can allow the lights to remain open until the normal sealant has cured (typically 24 hours) then it is not a problems. Or if you can ensure that most of the sealant is outside the box (i.e apply a layer between gland and outside before it is screwed in, and wipe away on interior). But having sealed lights with acid fumes inside is going to decrease the expected life a little!

 

[mattg4321]

What test equipment do you have out of interest?

 

[rjdainty1]

Thanks for your comments again @pc1966 , a little disappointing to have bought and fitted the wrong item but all part of the learning process I guess.

So I can order these or the plastic ones that you’ve also mentioned, I’d have thought the metal would be better though - do you think the ones I’ve linked would be suitable? If so I’ll get them ordered along with some sealant and remove what I’ve installed before it rains

Oh and @mattg4321 , I don’t have any test kit as such, just wired to three pin plug to test. A bit of a ball ache wiring each in turn but at least it seemed safe and I was able to see each light working.

Thanks

 

[pc1966]

The ones you have are not waterproof in any way - the rubber covers are really only for dust/damp. So if they are outdoors you will get moisture passing in to the cable armour and in to the lights. If you can get and fit the outdoor ones it would be better than the plastic glands, but I would still apply some sealant to the gland-box interface as sadly outdoor glands do not come with any sort of seal there (I think the "SAW Storm glands" do but at higher price).

I think @mattg4321 concern is legitimate - that whatever you do it has to be safe. A professional electrician would do several 'dead' tests before powering it up and probably one 'live' test to make sure it is safe:

• Insulation resistance (so there is no sign of damaged insulation at 500V DC)
• Earth continuity (to be sure that the lights are effectively connected back to the supply)
• Overall loop fault impedance (to check the supply fuse/breaker will clear quickly enough)

Good workmanship should result in all being OK, but only testing establishes it really is!
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Also mentioned above is the building regulations / Part P stuff where any new circuit has to be tested and notified. If this is not something being added to your CU, say it is powered off a 13A plug (with 3A fuse, of course) that does not apply.

But basic safety still does, and it must be from an outlet that is RCD protected!

 

[rjdainty1]

Thanks @pc1966

So the ones I linked to in my last post were metal but also mention external and seem to have rubber seals, are you saying that you think these are okay if used with sealant (that was my plan).

Otherwise I can get the plastic ones you referenced in your previous post. I just figured the metal would be a bit more durable.

And thanks for the comments regarding safety - taken on board.

 

[pc1966]

So the ones I linked to in my last post were metal but also mention external and seem to have rubber seals, are you saying that you think these are okay if used with sealant (that was my plan).

An indoor gland has 2 metal parts, one that fits the box (with a nut inside) and the other that screw on to it clamping the armour wires.

The outdoor SWA glands have a 3rd part, it goes over the armour-clamp and has a sealing ring gripping the cable's outer sheath to keep water out of the armour.

However, the usual SWA glands are not really waterproof for submersion, etc, as they lack full sealing on the screw threads, and they do not have any sealing washer between the first part and the box. For the gland-to-box you can use silicone or similar that sets. For the screw thread part you can use some grease or Vaseline.

But if using normal engineering grease be aware it is an extreme pressure lubricant so it is easer to over-tighten as the compressive force for a given torque can be 2-3 times higher than dry metal.

The plastic ones are easier to get a good seal with, providing you do not need the higher strength and armour connection, but even they need some sealant between the gland and box as they are not perfect there (the plastic has some ability to compress to match the box surface, but it has to be quite a clean & neat fit to do so).

 

[rjdainty1]

Okay thanks for the explanation. I’ll go ahead with the plastic ones you linked, along with some sealant.

Thanks

 

[Markyd]

So how are you going to notify the work and complete a cert for it?......