In part 1, I left the tale at the point where the DNO had provided a supply to the premises, most probably with a TN-C-S earthing scheme for a new build. For the purposes of this article, I’ll assume you have been provided with a supply capable of running a TN-C-S earthing scheme, and that the incoming supply looks something like the diagram below, once the house is completed: Continue reading “Domestic electrical installation earthing and circuit protection – part 2”
Some have asked me for copies of stuff, or links to downloads, and rather than email them out individually I’ve added them to the “downloads” menu at the top of the home page here.
The link to the Stroma FSAP download page is just that, a link. Stroma offer their SAP software on a free basis, so anyone can use it to do their SAP calculations. However, only an accredited assessor is allowed to officially submit the reports, so although useful from an educational perspective you have to be aware that the reports that are produced from this free software will be watermarked “DRAFT”*** and will not have an assessors name or registration number on.
The spreadsheets were all written by me to help me get my head around some of the things when I was first designing our house, to allow some “quick and dirty” comparisons of different build methods and also to assist when it came to doing the VAT return at the end (HMRC will accept these printed form replicas without any problem at all, BTW). Continue reading “Downloads from the top menu”
This is a, rather lengthy (even though it was intended to be brief), bit on the history and background of domestic electricity supply earthing and circuit protection systems, and why they are important, to help understand why we have earthing and circuit protection schemes in the first place, what they are for, how they’ve evolved, and why, together with the expertise of the electricians we employed, I made the choices I did.
Like any history, it’s written from my personal perspective and reflects my view on why certain things were done at certain times. Much of the reasoning for some of the decision making has been lost, so inevitably some of the historical aspects are a reasonable guess. using information from multiple sources. The later history is more accurate, as I was indirectly involved with rule making from around the time of harmonisation onwards, specifically with the formulation and application of the LV Directive and the EMC Directive.
This may sound an odd thing to write, but there is NO such thing as a safe electrical installation, and there never can be. Safety is not a finite entity; no matter how hard we try we cannot remove all of the risk, and some risk ALWAYS remains. All we can ever do is try to mitigate the remaining risks by a carefully thought-through design, balancing what we personally find acceptable in terms of risk, cost and convenience, with what is within the requirements of the regulations that apply at the time your installation is installed. Continue reading “Domestic electrical installation earthing and circuit protection – part 1”
This blog is partly a re-creation of our original house self-build blog from the now defunct Ebuild forum and also a means for me to present a commercial-free view of the process of self-building and some of the many challenges it presents. Continue reading “Introduction”