Wiring Matters – Issue 81 – July 2020

Here is what you will find in the July 2020 (Issue 81) of the IET Wiring Matters magazine.

History of insulation resistance testing

There has been a lot of activity on the IET Engineering Communities forum recently regarding the background of the 1 megohm minimum value for insulation resistance. Let’s take a look at how this value was arrived at in BS 7671:2018+A1:2020.

Draft for Public Comment: IET Code of Practice for Electrical Energy Storage Systems, 2nd Edition

The IET are happy to announce that the Draft for Public Comment for IET Code of Practice for Electrical Energy Storage Systems 2nd Edition is now live.

This Code of Practice looks at Electrical Energy Storage System (EESS) applications and provides information for practitioners to safely and effectively specify, design, install, commission, operate and maintain a system. This 2nd Edition has been updated to take account of developments in the industry, and progress in standardisation.

The all-new 5th Edition of the IET Code of Practice for In-Service Inspection and Testing of Electrical Equipment

In this article, James Eade, author of the 5th Edition, gives a brief insight into the changes to this important Code, due for publication later this year.

Amps per Pound

The idea of sizing a cable to reduce energy loss in distribution is nothing new and has been considered for many years, but with competitive tendering for work and the continual search for cost reductions (also known as ‘value engineering’), the modern design of an electrical installation tries to reduce the materials utilised to a minimum.

Asbestos guidance for electricians

Asbestos was widely used in building construction, both as a building material and for its useful insulation and fire protection properties, for many years during the 20th century.

Its use was progressively reduced between the 1970s and 1999 when all remaining forms were finally prohibited in the UK with the implementation of the Asbestos (Prohibitions) (Amendment) Regulations 1999. Asbestos has also been removed from various properties over the years for various reasons, for example, because of damaged material, or for refurbishment and demolition, but a substantial proportion of the original products still remain. These materials, if undetected, can present an ongoing risk to workers carrying out building repair and maintenance or improvement and refurbishment work. Workers at potential risk include electricians and other building trades.