hi all
On all the courses I have just done including 2391 they say to calculate all except radial and ring final circuits with a suitable plug in lead. I even was told to do it this way for practical assessment and then compare to rule of thumb max measured tabulated 80% values In GN3 , they just say for safety reasons and whats reasonable not to put yourself in danger with regard to Elecy at work regs e.g. They state not to work live unless in all circumstances its unreasonable to work dead and in all circumstances its reasonable to work live and safety precautions are taken to prevent injury by using suitable PPE which is a statutory document and supersedes non stat and codes of practice and also with regards to Health and safety regarding working at heights as IQ electrical said e.g 12 tread step ladders , but at same time we had questions asking how to conduct an earth fault loop impedence on a lighting circuit in a commercial or industrial premises and also says in all the non statutory documents either way is acceptable .It Seems there is lots of contradictory info regarding different methods. too much confusion? As wayne has said this is how gn3 says to carry our Zs on a pir . The tutor also said Zs is the most important test as it not only proves there is a continuity in the loop, but also confirmes ,polarity and voltage and to ensure the Zs is low enough for a sufficiently high enough fault current to ensure the protective device will actually operate in the required time to meet max disconnection times, but again tutor still said to calculate as this is the true value where possible, measuring not accurate as it includes parallel earth paths from the main protective bonding conductors etc etc ?????????????? confused or what please dont shoot me this is only what ive been taught by my betters
I am with lenny and you guys, but if asked i am with calculating lol so do i or dont i measure that is the question?????????
