Issue 72 - September 2018

In this issue we have another insight into the new edition of BS 7671, a piece detailing impressed voltages and one of our regular contributors goes through the changes to ENA Engineering Recommendation P23.

Impressed Voltages

Leon Markwell, Senior Engineer at the IET, provides us with information about impressed voltages, which relates to his forthcoming publication Guidance Note 2: Isolation & Switching, which is due for publication in Autumn 2018.

Earth fault loop impedance revision of ENA Engineering Recommendation P23

In this article, Graham Kenyon provides an overview of the changes and considers how designers should treat earth fault loop impedance (Ze) in calculations for existing and, if required, new installations.

The 18th edition (BS 7671:2018) launch - revisited

This is the second of two articles on the launch of the 18th Edition (BS 7671:2018).