Hello,
Not been on here for a few years. This place was a great help during my renovation including full DIY rewire. That all went fine in the end - notified, did all work myself including inspection and testing, submitted EIC and got my completion cert (and added to some council approved electricians who don't belong to a scheme list, which was nice).
Anyway - that place is now sold and I live in Norway. Been renting apartments for three years whilst saving, and now have bought a house and just moved in last week. There's some extremely knowledgeable folks on here, and I'd be interested in some feedback/opinions on my place's electrics - safety and just generally what the heck is it?
One thing I notice in practically every property I've been to over here is unearthed sockets are everywhere, and my place is the same. Makes me feel concerned. It mightn't be so bad by itself, but couple that with the fact the country uses almost entirely electric heating, you commonly see class 1 metal cased panel heaters plugged into these unearthed sockets. Plus computers, freezers, etc. Only kitchens and bathrooms usually have earthed sockets.
What I'm wondering is, is there something inherently safer and less concerning about that situation over here by account of the network or the buildings? I.e. the buildings are almost entirely wood which I guess is reasonably insulating. My house has a concrete basement level though. Very new builds tend to have earthed throughout, but unearthed sockets can still be purchased from the local DIY shed.
I read that the network is mostly actually IT (something to do with the ground being all rock and not being able to get reliable earth connections or something) with only new build stuff now TN C S. Not yet sure what mine is though or how to reliably find out. Now I know how IT is from a diagram, but I don't fully understand the physics of how it would behave, specifically with regards to touching a phase live due to a fault/accident whilst standing on my wood floor.
I mean does IT mean it's fundamentally safer for me to touch live while standing on earth as there is no low impedance path back to the transformer to complete the circuit, or am I not getting it?
I measure about 120 - 130 V between live and my house's earth or between neutral and earth. Is that some indication or proof the network is IT? Surely those figures wouldn't be possible on a TN network? Again I'm not sure about that.
At least the cabling seems to have earth present (except for lighting I think), so should I be running round replacing all sockets with earthed ones so I sleep better at night? If the network is really IT, what does a consumer protective earth actually do? I mean a live to earth fault wont neccessarily pull enough current to trip an MCB, right? So might just leave a metal case at live voltage even if earthed, or am I talking crap? Would trip an RCD though, I guess, which I dont have :/
The next funny thing is I have a three phase supply. Well I initially thought I did, but now I have a different theory. Here's some terrible pictures of the CU - sorry I'm not sure what box the real camera is in...
At least it's spacious . Nice mix of brown and blue, or just use black for everything if they fancied it. The incommer is the three wires (black brown and off-white) and I think the main earth lead wrapped in green and yellow tape (but I cant see if that is actually within the incomming service or seperate. So if that is three phases, where is my nuetral? I'm therefore thinking maybe I actually have two phases and neutral? Is that even a thing? The only thing I have found so far that uses more than one phase is the cooker hob, but I'm pretty certain that is 400V single phase as it clearly is wired with two phases and earth. Meter is three phase and the three incomming wires all go through the meter (but neutral does anyway in single phase). Could it really be two phase and neutral?
I guess I need to pop off some panels and have a better look and maybe take some measurements to confirm.
That lone RCD is the other odd thing in my opinion. It is the feed to part of the basement that was built as a standalone apartment with its own CU, so it can be rented out seperately and have a separate electric bill (although the previous owners never used it as such and there is no separate meter, but one could be added I guess?). Surely it's stupid to have the RCD in the main house CU? If I do rent the basement apartment out (we intend to) and if I ever go away and the tennant does something to trip the RCD, they are screwed till i get back, right? Surely I want the RCD in the basement CU and just a switch in the main CU (or nothing - just a henley type of thing to directly feed the basement)? Nice that they decided to RCD protect the tenants, but not the main house.
OK this is long enough already. Thanks for your time anybody who made it this far. Any opinions appreciated.
EDIT: Ah that shows how long since I've been here - I completely forgot there is a whole different forum for electrics outside UK that I suppose this ought to be in . Mods please move if you like. On the other hand, it might get read in here
Not been on here for a few years. This place was a great help during my renovation including full DIY rewire. That all went fine in the end - notified, did all work myself including inspection and testing, submitted EIC and got my completion cert (and added to some council approved electricians who don't belong to a scheme list, which was nice).
Anyway - that place is now sold and I live in Norway. Been renting apartments for three years whilst saving, and now have bought a house and just moved in last week. There's some extremely knowledgeable folks on here, and I'd be interested in some feedback/opinions on my place's electrics - safety and just generally what the heck is it?
One thing I notice in practically every property I've been to over here is unearthed sockets are everywhere, and my place is the same. Makes me feel concerned. It mightn't be so bad by itself, but couple that with the fact the country uses almost entirely electric heating, you commonly see class 1 metal cased panel heaters plugged into these unearthed sockets. Plus computers, freezers, etc. Only kitchens and bathrooms usually have earthed sockets.
What I'm wondering is, is there something inherently safer and less concerning about that situation over here by account of the network or the buildings? I.e. the buildings are almost entirely wood which I guess is reasonably insulating. My house has a concrete basement level though. Very new builds tend to have earthed throughout, but unearthed sockets can still be purchased from the local DIY shed.
I read that the network is mostly actually IT (something to do with the ground being all rock and not being able to get reliable earth connections or something) with only new build stuff now TN C S. Not yet sure what mine is though or how to reliably find out. Now I know how IT is from a diagram, but I don't fully understand the physics of how it would behave, specifically with regards to touching a phase live due to a fault/accident whilst standing on my wood floor.
I mean does IT mean it's fundamentally safer for me to touch live while standing on earth as there is no low impedance path back to the transformer to complete the circuit, or am I not getting it?
I measure about 120 - 130 V between live and my house's earth or between neutral and earth. Is that some indication or proof the network is IT? Surely those figures wouldn't be possible on a TN network? Again I'm not sure about that.
At least the cabling seems to have earth present (except for lighting I think), so should I be running round replacing all sockets with earthed ones so I sleep better at night? If the network is really IT, what does a consumer protective earth actually do? I mean a live to earth fault wont neccessarily pull enough current to trip an MCB, right? So might just leave a metal case at live voltage even if earthed, or am I talking crap? Would trip an RCD though, I guess, which I dont have :/
The next funny thing is I have a three phase supply. Well I initially thought I did, but now I have a different theory. Here's some terrible pictures of the CU - sorry I'm not sure what box the real camera is in...
At least it's spacious . Nice mix of brown and blue, or just use black for everything if they fancied it. The incommer is the three wires (black brown and off-white) and I think the main earth lead wrapped in green and yellow tape (but I cant see if that is actually within the incomming service or seperate. So if that is three phases, where is my nuetral? I'm therefore thinking maybe I actually have two phases and neutral? Is that even a thing? The only thing I have found so far that uses more than one phase is the cooker hob, but I'm pretty certain that is 400V single phase as it clearly is wired with two phases and earth. Meter is three phase and the three incomming wires all go through the meter (but neutral does anyway in single phase). Could it really be two phase and neutral?
I guess I need to pop off some panels and have a better look and maybe take some measurements to confirm.
That lone RCD is the other odd thing in my opinion. It is the feed to part of the basement that was built as a standalone apartment with its own CU, so it can be rented out seperately and have a separate electric bill (although the previous owners never used it as such and there is no separate meter, but one could be added I guess?). Surely it's stupid to have the RCD in the main house CU? If I do rent the basement apartment out (we intend to) and if I ever go away and the tennant does something to trip the RCD, they are screwed till i get back, right? Surely I want the RCD in the basement CU and just a switch in the main CU (or nothing - just a henley type of thing to directly feed the basement)? Nice that they decided to RCD protect the tenants, but not the main house.
OK this is long enough already. Thanks for your time anybody who made it this far. Any opinions appreciated.
EDIT: Ah that shows how long since I've been here - I completely forgot there is a whole different forum for electrics outside UK that I suppose this ought to be in . Mods please move if you like. On the other hand, it might get read in here