Interesting point, but heatshrink is considered electrical insulation, and is as tough as a cable sheath. If it didn't meet this standard, it would be sod all use to us.
How should I gland this swa?
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Do you know what, I NEVER had it in my mind to use Heat shrink in these cases, seriously, never!
So, If it was me,
Constant tension spring on armour
Another layer of shrink on cores ( belt and braces )
Shrink over cores AND inner bedding
Shrink over spring
Adhesive shrink if possible
Simples
Funfact. I have some Raychem BFO heatshrink which is marked up,as 'warning conductive' so be careful,out there
So, If it was me,
Constant tension spring on armour
Another layer of shrink on cores ( belt and braces )
Shrink over cores AND inner bedding
Shrink over spring
Adhesive shrink if possible
Simples
Funfact. I have some Raychem BFO heatshrink which is marked up,as 'warning conductive' so be careful,out there
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Does that heatshrink happen to be black in colour?
I remember being involved in a new switchboard that had to get a ton of panel edge protector strip (similar to grommet strip) changed because it was black and found to be conducive, something to do with the carbon that was used to colour it.
There might be some slack armour in the wall, worth a look!
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I wouldn't regard a meter box key as a tool, as it's designed for any member of the general public to use.
Not quite sure where that leaves a screwdriver
I understood the phrase 'use of a tool' to not actually make any reference to the competence of the tool user? Just the fact that a door or lid cannot be accidentally opened without someone first intentionally getting "the tool"..
Not much different to any form of enclosure really? However.. the number of meter-boxes I see with broken latch, broken hinge and Gaffa tape as the closing method wouldn't bode well as ensuring the need for a Tool!!
I would agree with that.
another little fun fact for you. I had a temproary job working for Hellerman Tyton when they had a factory in Plymouth, inspecting hetshrink and the materials used for the black underground cable joint sleeves. I used to mould a 6inch square of the material, and then put it in a high voltage rig and blast it with a 20,000V spark. It was like Frankenstein's lab - great fun!
Dear me... all this talk about "extraneous conductive part" ???
The armour of a cable is there for TWO reasons; 1, to be used as a CPC, and 2, To protect those that may damage the cable from electric shock.
It is NOT NOT NOT just there to provide mechanical protection, it is to provide shock protection to those that might damage the cable too, which is why you have to use armoured cable or an EARTHED metal plate if a cable is less than 2" deep in a wall..
You cannot earth the armour ONLY at the load end because you think it is merely an extraneous part, it is not, as i said, it is an integral part of the electrical protection of the cable and therefore must be earthed at the supply end.
Disagree??, ok, what if someone was to spike the cable near the supply end??? You have gone and doubled the length of the earth fault loop. What about ADS?? what about EFLI?? How is the supply going to disconnect in the required time???
What if a cable is disused [say pot ended] or someone decides to TT wherever it is going??? or disconnects the "earth" to the armour for any other reason. You now have a cable with no shock protection for those that may damage it..
If you are going to do that you might as well have used twin and earth...
john..
The armour of a cable is there for TWO reasons; 1, to be used as a CPC, and 2, To protect those that may damage the cable from electric shock.
It is NOT NOT NOT just there to provide mechanical protection, it is to provide shock protection to those that might damage the cable too, which is why you have to use armoured cable or an EARTHED metal plate if a cable is less than 2" deep in a wall..
You cannot earth the armour ONLY at the load end because you think it is merely an extraneous part, it is not, as i said, it is an integral part of the electrical protection of the cable and therefore must be earthed at the supply end.
Disagree??, ok, what if someone was to spike the cable near the supply end??? You have gone and doubled the length of the earth fault loop. What about ADS?? what about EFLI?? How is the supply going to disconnect in the required time???
What if a cable is disused [say pot ended] or someone decides to TT wherever it is going??? or disconnects the "earth" to the armour for any other reason. You now have a cable with no shock protection for those that may damage it..
If you are going to do that you might as well have used twin and earth...
john..
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I will always earth at both ends. I had an instance that @apprentice87 describes. SWA cable supplying external lights, a very long run using a core as the cpc. The armour was earthed at all points along the run but not at the DB (not glanded to the board). Zs was satisfied at the furthest point (type C, 10A) but a Zs to the armour at the DB was way too high. This can be the case either way around.
Doesnt anyone use...... Self Amalgam tape anymore? easier than heatshrink......secure it with a worm/hose clip, razor wire , yellow stickers and write RA if you want
When working with SWA and outside light fittings not designed to take a cable bigger than a gnats needle , just tape up the end with SA tape after testing earth to armour........and now......what is wrong with the world....keep it simple.... WHY am I stuck in BOLD TYPE..anyone? ...ahhhh thats better.
Cured that for you
When working with SWA and outside light fittings not designed to take a cable bigger than a gnats needle , just tape up the end with SA tape after testing earth to armour........and now......what is wrong with the world....keep it simple.... WHY am I stuck in BOLD TYPE..anyone? ...ahhhh thats better.
Cured that for you
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I use tape quite a lot, but only certain brands have an official ampage rating.
not for SWA Poni
A PIB tape would be better for the application as it won't rip / tear when applying it over the hose clip
I thought that the idea of electrical insulating tape was that it did not carry current? that's what the
was about
Ah right, neoprene self amalgamating tape does insulate, but because of the nature of the way it is applied, it's insulating properties are not defineable. Only Alpha tape has recognised insulation figures, however, I've used neoprene tape for years as it is a very good product, and I'm too tight to pay for Alpha tapeI thought that the idea of electrical insulating tape was that it did not carry current? that's what the
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If you are bothered about the single insulated tails, why not buy a length of the largest PVC trunking you can find and enclose the tails from the entry to the box to the isolator inside the trunking.
It does not have to look pretty.
It does not have to look pretty.
its not looking that pretty now,
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