SWA armour sizes as CPC

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Mr Sworld

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Here is a good web page relating to SWA and the suitability of the armour as CPC.
 
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Link does not work I get an error 404.

Would be nice if it was repaired could be usefull info for some.

 
I thought that the point of using K was to establish the correct CSA for current carrying capacity.

 
But if you read it closely it was written for the 16th edition.
If you join the IET forum, you can ask John Peckham for his updated version.

 
I thought that the point of using K was to establish the correct CSA for current carrying capacity.
Fine, but just out of curiosity what exactly is the current carrying capacity, in ampere,s of the steel wire sheath for the various sizes?

the link gives the CSA but you would need also the resistivity of the steel to get the capacity, would you not?

 
does this not involve money changing hands?
Not that I'm aware of.

John has mentioned a couple of times that if people PM him their Email addresses, he will send them a copy of his report. Recently he has offered the updated version.

 
Fine, but just out of curiosity what exactly is the current carrying capacity, in ampere,s of the steel wire sheath for the various sizes?the link gives the CSA but you would need also the resistivity of the steel to get the capacity, would you not?
There are two parameters to consider. The thermal withstand, which is what the k formula is intended to be used for.

Then there is the equivelant conductivity, to be determined for if the SWA is to be used as a bonding conductor.

The Table used in the link shows the minimum CSA required for the SWA using the K formula. It then shows the actual CSA of the SWA, which in the majority of cases exceeds the minimum.

Here is some reading material regarding the use of the SWA as a CPC.

http://www.wiley.com//legacy/wileychi/eca_wiringregulations/supp/Appendix_16.pdf

 
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