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You would be need the swa steel to be 136mm for it to have the same conductivity as equal to a 16mm copper equivalentThe csa of the steele armour on a 25mm2 2core SWA equates to 60mm2 which in terms of CU eqates to 26.6mm2
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You would be need the swa steel to be 136mm for it to have the same conductivity as equal to a 16mm copper equivalentThe csa of the steele armour on a 25mm2 2core SWA equates to 60mm2 which in terms of CU eqates to 26.6mm2
You would be need the swa steel to be 136mm for it to have the same conductivity as equal to a 16mm copper equivalent
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I use gn8 tables or manufacturer data for actual CSA of the steel armour but like has been said the copper-steel ratio is around 8.5 difference in conductivity so as an example if a steel conductor was used as a protective bonding conductor then the CSA of the steel would need to be 85mm to be the equivalent of the required 10mm copper
I always use M6 25mm brass nuts, washer and bolts as it’s always the way I was tought and is my preference.
Piranha nuts are a great alternative, tho when using larger glands say 32 mm and up,I’ve not seen them made for this size
Brass for me as well, reduces the risk of bi-metal corrosion and you can undo them in ten years time.
I use gn8 tables or manufacturer data for actual CSA of the steel armour but like has been said the copper-steel ratio is around 8.5 difference in conductivity so as an example if a steel conductor was used as a protective bonding conductor then the CSA of the steel would need to be 85mm to be the equivalent of the required 10mm copper
is this question real really , as most on hear know the armourings are used as protection for the cable which is usually used when its installed in areas likely to get mechanically damaged ,ie buried ,spade digging ,and secondly a lot of sparks still use this as a cpc to keep the cost down and not include a extra core as a earth , either way the armourings need to be earthed, this is done via a gland , banjo nut and bolt for a solid earth and flylead . its beggers belief to think there are guys out there doing work not knowing such a thing
It has the banjo fitted so it must be fine!!!
What on earth did they manage to do to that gland to rip off the end of the clamp nut?
If you are utilising the armour as the circuit cpc then yes I would use the Adiabatic or the tables and size the fly lead accordingly.Without having my books to hand, having not (yet) been taught this and calling on the years of valuable experience available here, how does one select the CSA of the fly-lead?
Should it follow the usual rules for sizing CPCs - either be the same CSA as the live conductors or be selected by calculation using the adiabatic equation?
Surely unless it is correctly sized it may also prove unreliable under fault conditions?
Without having my books to hand, having not (yet) been taught this and calling on the years of valuable experience available here, how does one select the CSA of the fly-lead?
Should it follow the usual rules for sizing CPCs - either be the same CSA as the live conductors or be selected by calculation using the adiabatic equation?
Surely unless it is correctly sized it may also prove unreliable under fault conditions?
Just curious what they are called?I use these when terminating into a plastic box. Great way to maintain earth continuity
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It's a Wiska EMC Earth ClampJust curious what they are called?
Generally you don't somebody on more money than you does who drives a nicer car than you.
On a glaxco chemical plant I was on recently all the earthing flies were 6mm.
There was a big debate going on because EX SWA glands the sheath were left off because not required. They liked it in the end as no armour showing anyway.
Lots of earthing going on if the pipes resistance was greater than 10 ohms across the flange then flies were put between the flanges on pipes.
The Electrical engineer in the office had the final say on what went down with his brand new Audi in the car park to prove it.
6mm is the norm for all Petro-chemical sites, hope they used copper tube lugs rather than the crappy yellow lugs the fail in no time!
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