What's the Banjo doing?

[KeenPensioner]

As a trainee can I ask why the banjo is on the outside of the Wiska box. I understand that the earthing of the SWA must be maintained but would having the banjo outside mean you need to drill through the IP66 box to connect to earth and by doing that are you not compromising the IP rating? I understand the earth locknut is inside the box so what function does the banjo have when it's outside the box and not connected to anything?

 

[brianmoooore]

It tends to act as a load spreading washer, allowing the nut to be tighter without the gland digging into the plastic of the box.
IP23 is arguably the minimum for a box mounted where that one is, so a little compromising of the IP66 rating is acceptable.

 

[mainline]

As a trainee can I ask why the banjo is on the outside of the Wiska box. I understand that the earthing of the SWA must be maintained but would having the banjo outside mean you need to drill through the IP66 box to connect to earth and by doing that are you not compromising the IP rating? I understand the earth locknut is inside the box so what function does the banjo have when it's outside the box and not connected to anything?
View attachment 110348

In that configuration, you would have to drill a hole and nut and bolt a fly lead to earth the armour.
The easiest way is to use an earth plate.

 

[KeenPensioner]

In that configuration, you would have to drill a hole and nut and bolt a fly lead to earth the armour.
The easiest way is to use an earth plate.

Thanks for taking the time to reply. I found this on an electricians youTube video and can't understand why he didn't use an pirana nut or earth plate like this?

 

[westward10]

Those earthing nuts will not normally fit inside a Wiska box. There is an earthing bar made for the Wiska 308 which are brilliant.

EC308 | Wiska | IP66/67 Combi JB Earth Clamp | 2 Pack | Superlec Direct

www.superlecdirect.com

 

[brianmoooore]

can't understand why he didn't use an pirana nut or earth plate like this?

SWA glands usually come in a sealed packet containing 2 x glands, 2 x shrouds, 2 x galv. locknuts and 2 x brass banjos, so banjos tend to get used.

 

[KeenPensioner]

In that configuration, you would have to drill a hole and nut and bolt a fly lead to earth the armour.
The easiest way is to use an earth plate.

Thanks for taking the time to reply. What I don't understand is why he put the banjo outside the Wiska box?

 

[SJD]

Thanks for taking the time to reply. What I don't understand is why he put the banjo outside the Wiska box?

The banjo won't fit inside the Wiska, the inside wall is not flat. Normally I'd fit an earth bar inside that has a profile machined to fit.

See post #5. There are different earth bars available to suit different Wiska sizes, the '308 is the most common size.

 

[KeenPensioner]

The banjo won't fit inside the Wiska, the inside wall is not flat. Normally I'd fit an earth bar inside that has a profile machined to fit.

See post #5. There are different earth bars available to suit different Wiska sizes, the '308 is the most common size.

Thanks very much to you and all who replied - that's answred it. I know what you mean by the Earth Clamp Bar for SWA.

 

[littlespark]

Thanks very much to you and all who replied - that's answred it. I know what you mean by the Earth Clamp Bar for SWA.
View attachment 110366

You’ll never get a hammer and chisel in there to tighten it up…..
Sorry, wrong thread.


There may be a situation where that particular banjo isn’t required at all. Whether it comes in the pack or not…. It isn’t always required.