blandy Posted November 9, 2022 Moderator Share Posted November 9, 2022 5 minutes ago, Seat68 said: All power is off in the conservatory. All switches off, put the breaker to on and it trips the electric. With power off it would make sense to remove the socket covers and inspect the connections inside - if a wire has come free, or been nibbled by tiny beasties. I once had a socket that caused the same that had a fried dead slug inside it. If you have a multimeter there's a few more things you could check, too like are live or neutral shorted to earth. 1 Link to comment Share on other sites More sharing options...
Seat68 Posted November 9, 2022 Share Posted November 9, 2022 1 minute ago, blandy said: With power off it would make sense to remove the socket covers and inspect the connections inside - if a wire has come free, or been nibbled by tiny beasties. I once had a socket that caused the same that had a fried dead slug inside it. If you have a multimeter there's a few more things you could check, too like are live or neutral shorted to earth. I am thinking in daylight and with power off ensure the cable going in is seated correctly. Not sure it can be anything else as nothing is on at plug/switch level. Link to comment Share on other sites More sharing options...
bickster Posted November 9, 2022 Moderator Share Posted November 9, 2022 2 hours ago, Seat68 said: ...nd an Alexa plugged in and I have been working in there happily for a couple of days. Not sure what is tripping it or the course of action to resolve it. Old fashioned fuse boxes would see me change the fuse but it’s just the mcb tripping. Any guidance? Has someone been playing The Beatles? 2 Link to comment Share on other sites More sharing options...
blandy Posted November 9, 2022 Moderator Share Posted November 9, 2022 4 minutes ago, Seat68 said: I am thinking in daylight and with power off ensure the cable going in is seated correctly. Not sure it can be anything else as nothing is on at plug/switch level. If you have a length of any wire, it would be worth con checking end to end, so you get the multimeter, set it to Ohms, put one probe on the Live at the feed in end (with power off, natch), and then run the length of wire from the conservatory socket 1 Live pin on the socket back to the multimeter and put the other prob onto the free end of the wire, Should be just a couple of Ohms. Then move the probe in the feed end to the Neutral and look for infinite Ohms (open cct), then repeat for the earth pin (also looking for open circuit). Then con check Neutral to Neutral and Earth to Earth, looking for a low impedance each time (1 or 2 Ohms). Depending on results (and assuming it's a spur) you may need to repeat between socket 1 and socket 2 - that way you're checking each wire is good, and no wires are shorted to any of the others. 1 Link to comment Share on other sites More sharing options...
blandy Posted November 9, 2022 Moderator Share Posted November 9, 2022 Like this (though this is slightly simplified between Skt 1 and 2, where there are 2 wires at the first terminal, but electrically in terms of continuity, it's as per the diagram 1 Link to comment Share on other sites More sharing options...
blandy Posted November 9, 2022 Moderator Share Posted November 9, 2022 Here's it updated with the double wires, @Seat68 Link to comment Share on other sites More sharing options...
Seat68 Posted November 9, 2022 Share Posted November 9, 2022 I may have questions on this when I have fetched my multimeter from my van and also a 50 metre length of wire. Link to comment Share on other sites More sharing options...
blandy Posted November 9, 2022 Moderator Share Posted November 9, 2022 1 minute ago, Seat68 said: a 50 metre length of wire Blimey, how big's your pad? Link to comment Share on other sites More sharing options...
Seat68 Posted November 9, 2022 Share Posted November 9, 2022 1 minute ago, blandy said: Blimey, how big's your pad? This is my crash pad. The conservatory is off the west wing. 2 Link to comment Share on other sites More sharing options...
tinker Posted November 9, 2022 VT Supporter Share Posted November 9, 2022 Are you sure it's just the conservatory that's powered from that MCB? Do you lose power to anything else when the breaker is off? Turn all the sockets off downstairs and see if the breaker stays in, have you got underfloor heating or an outdoor socket ? 1 Link to comment Share on other sites More sharing options...
blandy Posted November 9, 2022 Moderator Share Posted November 9, 2022 In terms of anticipating questions, the principle is to check that the resistance between things that are supposed to be connected together is very low, and that the resistance between things which should not be connected is very very high (open circuit). So the multimeter probes for things which should be connected go on to first Live at the house end, and then using the long piece of wire, Live at the far end (Skt 2). Then repeat for Neutral to Neutral The for Earth to Earth Then looking for open circuit, between Live and Neutral, then Live and Earth, then Neutral and Earth. The results may point at a problem. If they are all as expected, then from the (limited) information so far, the CB may be faulty. But we'll get to that later. It's more likely a wiring issue or a bad socket I'd guess. 1 Link to comment Share on other sites More sharing options...
Seat68 Posted November 9, 2022 Share Posted November 9, 2022 2 minutes ago, tinker said: Are you sure it's just the conservatory that's powered from that MCB? Do you lose power to anything else when the breaker is off? Turn all the sockets off downstairs and see if the breaker stays in, have you got underfloor heating or an outdoor socket ? There are further power sockets that run the shed, but they are turned off so as of now it’s just the conservatory Link to comment Share on other sites More sharing options...
blandy Posted November 9, 2022 Moderator Share Posted November 9, 2022 47 minutes ago, Seat68 said: There are further power sockets that run the shed, but they are turned off so as of now it’s just the conservatory It's not. Being turned off at the socket does not stop an electrical wiring problem tripping a CB. Edit - I should say why - it's because there are 2 sets of wires. The switched set (live is switched) is the power to THAT socket, but the switch does not stop the spur wires that go to the next socket in the line. I probably should make the diagram more complicated and show that 1 Link to comment Share on other sites More sharing options...
blandy Posted November 9, 2022 Moderator Share Posted November 9, 2022 @Seat68Zoomed In on old diagram with a switch shown to explain - you can see that the Live feed is looped on to the next socket, but the switch (when OFF) prevents Live getting to the actual plug socket. So any problem past a socket can still pop a breaker - which reminds me to say that the switches will need to be in the On position for the continuity checks unless you go to the actual wires, rather than using the external plug points - though you'll need to the sockets off the wall because of the Earth pin enabling the socket to get connected to a plug. Hope that makes sense. If not I can explain more - the earth pin on a normal plug pushes a lever in the socket which allows the Live and Neutral to connect to their respective socket points and thus to the plugged in item 1 Link to comment Share on other sites More sharing options...
blandy Posted November 9, 2022 Moderator Share Posted November 9, 2022 (edited) @Seat68 Here's a fuller diagram (shed not shown, but is to the left) Edited November 9, 2022 by blandy shed changed to Van 1 Link to comment Share on other sites More sharing options...
tinker Posted November 9, 2022 VT Supporter Share Posted November 9, 2022 1 hour ago, Seat68 said: There are further power sockets that run the shed, but they are turned off so as of now it’s just the conservatory Chances are it's going to be fault on the outside cable or circuits. I'm assuming it's an RCD that's tripping ( it will have a test button on it as well as a switch) TBH if its outside and it has a fault on it you have to be very careful as an electric shock outside can and does kill. Can't you leave the circuit off and run an extension into the conservatory as a temp measure? After that your best to try and physically find the problem while there's no power on the circuit , switch the breaker off and tape over the switch to prevent anyone accidentally turning it on. My guess is the cable outside will have a fault on it, a break , crushed, water ingress. This cable should be armoured cable.... Be careful, make sure it's isolated before you start poking around. 2 Link to comment Share on other sites More sharing options...
blandy Posted November 9, 2022 Moderator Share Posted November 9, 2022 10 minutes ago, tinker said: you have to be very careful as an electric shock outside can and does kill. Same for inside, to be pedantic. But yeah the shed and water ingress or critters seem quite likely as a cause, compared to something in the conservatory. Another thing is we assume it’s a spur, but we don’t know it is. Having lots of sockets on a spur isn’t brilliant. Link to comment Share on other sites More sharing options...
tinker Posted November 9, 2022 VT Supporter Share Posted November 9, 2022 13 minutes ago, blandy said: Same for inside, to be pedantic. But yeah the shed and water ingress or critters seem quite likely as a cause, compared to something in the conservatory. Another thing is we assume it’s a spur, but we don’t know it is. Having lots of sockets on a spur isn’t brilliant. Your right, I should have said increased risk. Electrical Safety First "Although electricity makes gardening much easier, wet conditions and contact with the ground means that the risk of injury or death from electric shock is much greater than the risk from using electrical equipment indoors." https://www.electricalsafetyfirst.org.uk/guidance/safety-around-the-home/garden-safety/ 2 Link to comment Share on other sites More sharing options...
Seat68 Posted November 10, 2022 Share Posted November 10, 2022 Through trial and error it seems that it was a heater that was plugged in. Everything else is now turned on and the electrics aren’t tripping. The only difference was a heater that was plugged in but turned off. 1 Link to comment Share on other sites More sharing options...
blandy Posted November 10, 2022 Moderator Share Posted November 10, 2022 8 minutes ago, Seat68 said: Through trial and error it seems that it was a heater that was plugged in. Everything else is now turned on and the electrics aren’t tripping. The only difference was a heater that was plugged in but turned off. Good. Now fix the heater. Loose wire in the plug, perhaps? Link to comment Share on other sites More sharing options...
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