Wiska WK308 Query

[lozarus]

I think I'm being dim here, but it's been a long day and I won't be able to sleep with this rolling around in my head - so can anyone help me out?

Replacing 3x junction boxes outside, serving 3 external lights which have become waterlogged due to poor original installation.

The first two boxes takes 2x 1.5 3c SWA plus a stuffing gland with h05 to the luminaire (so power in, flex to the fitting, and out to the next box). The final box obviously just has SWA in and the stuffing gland out.

Storm glands, magic gel and small wiska boxes ready. Also using the WK308 earthing bars in the boxes for maximum ease of installation.

Question is - I will obviously earth the SWA armour at source with a flylead / banjo, and also at the final fitting. As the two intermediate boxes will have WK308's linking the armour, is there any need to have an earth flylead at the middle two boxes?

Sounds petty I know but I've had to use smaller wiska boxes due to the awkward layout of the original installation - if it's not necessary then it's one less bit of flex for me to try and neatly and safely get in the box.

I can't think of why it wouldn't be fine, but for some unknown reason I'm questioning myself

Advice welcomed and thanks in advance as ever

 

[James]

All is fine with your plan. Sleep well

 

[Dartlec]

I think I'm being dim here, but it's been a long day and I won't be able to sleep with this rolling around in my head - so can anyone help me out?

Replacing 3x junction boxes outside, serving 3 external lights which have become waterlogged due to poor original installation.

The first two boxes takes 2x 1.5 3c SWA plus a stuffing gland with h05 to the luminaire (so power in, flex to the fitting, and out to the next box). The final box obviously just has SWA in and the stuffing gland out.

Storm glands, magic gel and small wiska boxes ready. Also using the WK308 earthing bars in the boxes for maximum ease of installation.

Question is - I will obviously earth the SWA armour at source with a flylead / banjo, and also at the final fitting. As the two intermediate boxes will have WK308's linking the armour, is there any need to have an earth flylead at the middle two boxes?

Sounds petty I know but I've had to use smaller wiska boxes due to the awkward layout of the original installation - if it's not necessary then it's one less bit of flex for me to try and neatly and safely get in the box.

I can't think of why it wouldn't be fine, but for some unknown reason I'm questioning myself

Advice welcomed and thanks in advance as ever

If you're using the earthing bar in the middle box then that ensures earth continuity of the armour I would think. Not installed them yet, but they seem to be cropping up in youtube videos a lot of late.

Seeing the thickness of them, I doubt a flylead in the middle box would add anything, don't see how they could come loose or lose connection without a banjo/flylead also being affected. Since you're not using the armour for CPC and earthing the armour at both ends, then I don't see the need for the extra belt and braces in the middle box.

tl;dr - Sounds like a perfectly good setup to me!

 

[lozarus]

Thanks both. Even now it seems obvious that it's perfectly adequate to maintain the armour continuity - after all, it's designed to provide a good link to the armour. A case of too much thinking.

If you're using the earthing bar in the middle box then that ensures earth continuity of the armour I would think. Not installed them yet, but they seem to be cropping up in youtube videos a lot of late.

Yeah theres some good products out at the moment. I don't buy into every fancy new thing, but I've used a few of these and they can make a fiddly job not quite so.