by ericmark »
Tue Aug 30, 2022 2:12 pm
This
https://electrical.theiet.org/media/169 ... ilding.pdf is dated, written before we needed all circuits RCD protected with a type A 30 mA RCD, but it is still a good guide.
Fig 3 is the bit which causes the most problems, with a TN-C-S supply we worry about the broken PEN more about that here
https://electrical.theiet.org/wiring-ma ... roken-pen/ so we need to be careful outside as although a MCB or RCD may remove the line and even the neutral, it leaves the earth connected, and if the true earth is a different voltage to the DNO earth current can flow between the two.
In Wales where I live work in the garden is considered as a special location, and needs registering with LABC, this requirement was removed in England, but we should aim to use all class II items in the garden, there has been of late problems with hot tubs, patio heaters, and EV charging points due to using class I equipment, and the cures can be quite complex.
The general public watch an electrician at work and think that's easy, but it's the bits you can't see, all jobs start with a method statement and risk assessment, that's all, not just electrical in many cases this may take seconds, for example there's the stop tap, likely water supply follows this route. Same with electrics, I survey the site, and normally quickly assess the risks.
But when remote from the site, this is hard, hence the links, it was a 5 year apprenticeship that I did, I like to think there was a reason it took so long, and that was not that I am a slow learner.