The ac resistance of conductors


In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the previous article, now may be a good time to do so. The ac resistance of a conductor is always larger than the dc resistance. The primary reasons for this are 'skin effect......Read More..

By Steven McFadyen on Wednesday, January 11, 2012

Restricted Earth Fault Protection


The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of REF protection....Read More..

By Steven McFadyen on Sunday, March 25, 2012

Cable Insulation Properties


Cable insulation is used to provide electrical separation between conductors of  a cable.  During the historical development of cables, numerous types of insulation have been employed.  During recent years, there has been some consolidation in the types of insulation used. This post provides some information on the more......Read More..

By Steven McFadyen on Tuesday, May 15, 2012

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