S/Y and SWA termination - stupid 25 characters

[gazdkw82]

I’m getting conflicting information from electricians at my works regarding the correct way to terminate SWA and more notably S/Y cable.

I was shown a few months ago that with s/y you only Earth the supply side of the shielding (like you would win data)

I was also under the impression you do the same with SWA.

Both are the case if you have a dedicated conductor for cpc. I thought this was the case so that there is no parallel cpc path.

Can anyone clear this up?

Thanks

 

[Rocboni]

Both ends should be terminated using the correct glands however it is only necessary to earth one end, preferably the supply end.

 

[Ian1981]

If I was glanding an swa from a plastic enclosure to another plastic enclosure then I would earth the supply end as it were with a banjo with a fly lead, if a separate cpc is being provided by another core
The other end I would gland but not provide the fly earth.
Or from a metal enclosure at the supply to say a plastic enclosure I’d do the same thing.
As long as the armour is connected to earth where ads is the choice for fault protection as it is considered an exposed conductive part.
I don’t like to use s/y and earthing the braid is for screening as the braid is not acceptable to be used as a cpc in its own right

 

[gazdkw82]

Thankyou Ian. That it how I see it.

Iv been told by a year 3 apprentice that they teach you to Earth both ends of the s/y as standard.

I can’t see how that is the right way

 

[Rocboni]

There's nothing wrong with earthing both ends as long as the braid is not used as the CPC

 

[gazdkw82]

HOw do you Earth both ends without it being part of the cpc?

So for example on the supply side the braids are connected with the cpc. If you do the same on the other side then it’s actually part of the cpc??

 

[Bobster]

HOw do you Earth both ends without it being part of the cpc?

So for example on the supply side the braids are connected with the cpc. If you do the same on the other side then it’s actually part of the cpc??

It's just ends up a parallel path. Not the cpc, it will need disconnecting at one end temporarily to test R2 the same way SWA should be.