forgot to get back to this! i did the tests as Lucien suggested (very clear, thanks) and all came back well. popped the lid and it basically looked as in pete's video. no secondary fuses, just that thermal trip. interestingly though i could now see that the 32A socket is clearly a later...
got given a 230V-110V site transformer today. probably reasonably old and been sitting in a garage for a while. so thought it'd be an idea to run some tests on it before chucking it into service?
i'm thinking that after an inspection for condition and obvious damage (even inside the case), i...
perfect Richard! excellent diagram and explanations so thanks a lot for that. that has clarified a lot of what i have been reading and now i feel like i'm understanding it. thanks!
thanks steve, i will check out the ESQCR reference as a point of interest, but maybe the question was phrased badly. i was really focusing on touch voltages under normal service, not fault conditions. am i shooting up the wrong tree here or can you point me in the direction i need to be looking? :)
cheers HT, that's certainly true with a broken PEN. i'm currently swimming around (drowning :sweatsmile:) in a pool of touch/step voltages and potential differences. trying to research and learn means i have lots of bits of information i need to relate into an understanding, so i may well be...
as usual, further reading brings up more questions than answers but i feel like (hope!) different pieces are starting to click together!
a) is one reason we are cautious with using TN-C-S earthing outdoors due to touch voltages that can occur between MET/installation earth and terrafirma/true...
to easily isolate the fitting from the rest of the house in case of neutral-earth fault tripping all circuits on the RCD? because an outdoor fitting is more likely to be suceptible to eventual water (or insect, etc.) ingress.
thanks for the response. i've drawn out some diagrams and am slowly getting this. athough i think i'm still a little hazy with the science as to how it happens, i think i'm understanding that the reason is to avoid a pd across the MET/installation earth and the neutral that could be an issue...
thanks Richard.
i see Table 52.3 suggests minimum permitted size TnE is 1,0mm² which will carry 5A all day long, and minimum flex is 0,75mm² which has a CCC of 6A before any derating so would be fine anyways.
there is also reference to specific appliances being allowed minimum CSA as specified...
okay, think i've compiled an attempt at everything now :)
cheers again for this steve. interesting to see if i'm thinking in the right places!
1.
no, BS 7671 714.1(v)
2.
no, Approved Document P, 2.7
3.
TN-C-S system so double pole isolation unneccessary. 537.1.2
i can't find anything to...
evening guys, i think i'm gonna need this one spelled out to me a little if anyone can help. everytime i think i've worked it out i just start to doubt myself and go in circles!
double pole isolation is required for TT but not TN systems where neutral can be said to be reliably connected to...
thanks for the responses Steve. certainly plenty to think about and a well thought out exercise.
rereading this i can really see your point!!
if you take the adding of an FCU and the replacement of the fan as individual actions then i can see how neither would be notifiable. in the same way...
2.
i would inspect/test the supplementary bonding (it's got to be there, 16th edition). am i required to for this? again, not sure. going to need some guidance here i feel..
3.
a) can't find anything saying a replacement fitting REQUIRES certification
b) a MWC may be an appropriate way of formalising work done.
but this again may be subject to change if i've missed a description of replacement works somewhere
top questions, really got me thinking, finding this really hard as i can't find much specific reference to replacement fittings or maintenance on fitting compared to alterations and additions. is there somewhere in BS7671 this is dealt with?
but here's a start..
1.
a) It is a replacement...
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