Advice on connecting cores of SWA cable inside junction box

[Tim Shand]

Hi everyone, I've added a junction box to an SWA cable in my garden to allow me to make a 3 way connection (I will fit an outside plug at later stage). I've fitted SWA glands, but I'm not sure how to join the cores inside the box! They're thicker than I'm used to. Should I use connectors (3 way)? If so, should they be 32 amp connectors? The breaker for this dedicated circuit is 32 amps. Why I'm partly confused is the previous house owners used 30 amp connectors on this circuit.

 

Also, the cores inside the cable are brown, black and grey. Am I correct that black should be earth and grey should be neutral (sleeved G&Y and blue respectively)?

 

I've reached out to the electrician I normally use, but he's on leave. I'm keen to finalise asap so I can concrete over the burried cable.

 

Thanks very much in advance for any help. Best wishes, Tim 

[elite]

Not a sparky...

 

I do grey as neutral and black as CPC (both sleeved at both ends to identify)

 

Don't forget to make sure your armour is connected to CPC too and you have continuity - wiska do some nice clamp bars

 

I'd use wagos to connect the cores, but do check they are rated to at least 32 amps (in your case)

 

 

[Gone West]

Also not a sparky, but I always use Piranhna Earth Nuts rather than the earth tags as they take up less room and are a neater solution.

 

https://www.tlc-direct.co.uk/Main_Index/Earthing_Index/Piranhna_Earth_Nuts/index.html

 

 

[Tim Shand]

Thanks so much for those helpful responses, Elite and Gone West. Cheers

[ProDave]

The gland nuts don't look tight.

 

If you stick with those glands drill a hole through them both and put a nut and bolt through.

 

What's the rating of the terminals supplied with the box? though not a lot of room.  I would have used a larger box.

[Kelvin]

I’d likely take that out and get a larger box. It’s far easier to make good connections when you have more room. 

[saveasteading]

I can advise on what I'd do different next time, having done it for the first time last month, after great advice from BH.

Bigger box. My sausage fingers needed lots of room for wiggling wires about and to get a spanner inside.

I'd def use the one from screwfix because the knockouts /seals are brilliant compared with what I tried first. SF say its unbranded  but that is wrong.

Wagos. I failed with screw connectors because there is so much wire and its stiff. Bought cheap connectors from SF and succeeded  but didn't like them so Wago next time.

Tightening the nuts. Really awkward and the extra space will help.

Earth. I used the supplied terminal but the one mentioned above seems much easier and more secure.

 

There is a good video on Facebook which helped with basics. 

I hate to think how long the first endvtook me. Several goes at it because I'd tangled or left something off.  Stop and think.

The other end 1/4 the time.

[ProDave]

1 hour ago, saveasteading said:

Tightening the nuts. Really awkward and the extra space will help.

Hold the gland nut inside the box with gland pliers, and tighten the outside of the fitting with a big spanner.  Must be done before fitting the cable into the fitting.

[saveasteading]

1 hour ago, ProDave said:

gland pliers

I was trying to use  them, but I think the noses are too wide and too thick. maybe mine are not actually gland pliers but something similar but chunkier.  I had to jam in a screwdriver to wedge the nut in position, and that worked.

[Tim Shand]

Thanks so much everyone. I got myself a bigger box - much better - and have tightened up the gland nuts (used Piranhna Earth Nuts instead). I also used Wagos for the connections. I will use ring crimps to connect to the earth nut.

 

Can you please advise on what way up the Piranhna Earth Nut should face? I can get it to screw much easier with the smooth side facing into the box. Is that correct?

 

Thanks again

[Onoff]

[andyscotland]

@Onoff is correct on the official manufacturer's instructions, normally it would be toothed side to the box (point 1 on the instructions) - the idea is that bites in so you tighten by rotating the gland body.

 

On a metal box, that is part of getting a good earth connection (through the biting teeth) between the nut and box body.

 

However, on a plastic box that obviously isn't an issue - it just needs to be screwed tight enough to get a solid mechanical connection. As you've already glanded the cable, you won't be able to rotate the gland and there's no benefit to undoing that - so put the smooth side to the wall and tighten the nut, as per point 3 on those instructions.

[Onoff]

A ring spanner of the size to match the locknut can be easier than an open ender especially when the gland is close to a screw boss. (Slip over the cable end with the power off/isolated). Worst case you get someone to hold the gland side with a spanner and you knock the locknut round / tight with a sharp, flat bladed screwdriver and a hammer. The steel screwdriver tip digs into the brass etc. Last report that really, ideally space your glands so you can get a spanner on. 

[Tim Shand]

Thanks so much everyone. All been really helpful. Definitely been a useful learning doing this and will be much faster (and easier) next time! Cheers, Tim