# HV Single Core Cables & Induced Screen Voltages

 I am aware that when using single core HV cables to supply a load, a voltage will be induced in the metalic screens. If the cable screens are earthed at both ends this will cause a current to flow in the screen and derate the cable current carrying capacity. There is not alot of information about this on the internet. Do you know of any simplified calculations to determine the current flow or approximations of derating factors? Best Regards, Shaun. asked 10/3/2013 Shaun T2

 The following post will help you with some derating factors you can use: Cable Sheath and Armour Loss A few years ago I came across a book [Underground power cables, by S.Y.King and N.A. Halfter]; which if I remember correctly may help you with calculating the current.   You can also Google for 'calculating sheath currents'.  I just tired and very quickly came across some papers with various methods of calculating sheath currents. answered 12/17/2014 Steven McFadyen 246

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