It's called bonding, it's protection against the socket becoming live, the fact you have voltage is the worrying part! You say live and neutral are transposed? I would be. Healing other sockets to see if they are th same.
Power keeps tripping out, how to diagnose?
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It's called bonding, it's protection against the socket becoming live, the fact you have voltage is the worrying part! You say live and neutral are transposed? I would be. Healing other sockets to see if they are th same.
I don't understand though, this "bonding" is making the screws on the front of the socket live so it's producing the opposite effect?
All the other sockets tested are wired correctly according to the socket tester.
Looking at the state of that socket I think I'm gonna need to get some rewiring work carried out, the live and neutral wires seem to be connected to the right pins, so that would suggest that they are wired wrong at the other end right?
Com’on guys if you’re not qualified electricians please stop guessing.
Bonding to the back plate is not required with plastic faceplate. Bonding is no longer required with metal faceplates if the back box has fixed lugs.
Extremely rare to see what you guys are describing in a domestic property.
Voltage found on the earth could be a disconnected earth (so check earth continuity back to the main earth terminal on the board) or it could be a fault live - earth.
A few quick tests by a qualified electrician will tell you this and have a solution within the hour.
Unsleeved earth is just bad workman ship.
Bonding to the back plate is not required with plastic faceplate. Bonding is no longer required with metal faceplates if the back box has fixed lugs.
Extremely rare to see what you guys are describing in a domestic property.
Voltage found on the earth could be a disconnected earth (so check earth continuity back to the main earth terminal on the board) or it could be a fault live - earth.
A few quick tests by a qualified electrician will tell you this and have a solution within the hour.
Unsleeved earth is just bad workman ship.
sounds like you have an earth leak somewhere in the system , even beyond the sockets on this MCB, and a poor quality earth strap, so the meter is picking up some changing (AC) potential on the earth, current that should be dissipated via a lower resistance earth strap.
In the daylight I would probably have been disabling the MCB's one by one to see when/if the 37v disappears. ....
I can't believe you wouldn't find that 37v on each socket's earth.
I don't think I'd be using a electrical power shower, in particular .... until the electrician has visited, and found an explanation.
They haven't replaced the incoming water supply with plastic piping recently or soemthing like that ?
In the daylight I would probably have been disabling the MCB's one by one to see when/if the 37v disappears. ....
I can't believe you wouldn't find that 37v on each socket's earth.
I don't think I'd be using a electrical power shower, in particular .... until the electrician has visited, and found an explanation.
They haven't replaced the incoming water supply with plastic piping recently or soemthing like that ?
If its only the one socket thats showing voltage on the earth, then this is the culprit (most likely). Whats the socket tester say, transposed live and neutral or earth fault?
What type of earthing arrangement does the property have? I ask as I often find buildings that have been converted by an electrician to PME (Protective Multiple Earthing) to have done so not knowing thats the incoming is not PME but SNE (Seperate Neutral and Earth) or TT (Terra Terra/Earth Spike) and causing issues like this because the earthing does not exist! (Im a supply Engineer I see this daily).
The socket tester says transposed live and neutral. I'm not sure what type of earthing arrangement we have, how do I tell?
Your mains incoming cable, take a picture of that. Where the cutout/mains fuse is there will either be an earth bar or obvious separate earthing for SNE or enclosed earth for PME. TT looks just like SNE.
Soldato
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Electrician came and found an intermittent live to earth fault when doing a 1000v test and said that the ring was also broken. Gave a couple of different options, could split the ring onto two 16amp breakers as there is space in the box which would rule out half the sockets so only half the sockets/wiring would need to be checked out on a subsequent visit to find the fault, but didn't believe we were in any immediate danger of a fire breaking out. So we've left it for now as we're going on holiday so will just shut that circuit off while we are away and then get someone back to do a more thorough workup.
Electrician came and found an intermittent live to earth fault when doing a 1000v test and said that the ring was also broken. Gave a couple of different options, could split the ring onto two 16amp breakers as there is space in the box which would rule out half the sockets so only half the sockets/wiring would need to be checked out on a subsequent visit to find the fault, but didn't believe we were in any immediate danger of a fire breaking out. So we've left it for now as we're going on holiday so will just shut that circuit off while we are away and then get someone back to do a more thorough workup.
You have an SNE installation by the looks of that, earth to live is far more dangerous in this situation. I doubt the broken ring main is your issue though more likely insulation given out causing the intermittent live and short.
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Looks like you may need an EICR
Judging by the size of the twins at the top of the board I wouldn't be surprised if it's aluminium cable, or a nice case of green goo somewhere. An open circuit on your ring wouldn't trip the MCB, would just mean the MCB is over-rated. However, in my experience. The culprit will either be behind a socket or a joint due to an alteration in the circuit. Either to change a face plate or to add an accessory in. Screw slightly through a conductor behind a faceplate finally giving up.
Your property would fail an EICR, be wasting your time with one. money would be better spent upgrading the consumer unit. However, a house with 7 circuits shouldn't take long to test.
Also, who meggers a circuit on 1000v?!
Your property would fail an EICR, be wasting your time with one. money would be better spent upgrading the consumer unit. However, a house with 7 circuits shouldn't take long to test.
Also, who meggers a circuit on 1000v?!
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from his expert post - I think he knows that ?
... was more interested to hear if 1000v is too high and you would expect insulation to fail ?
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It can damage the insulation i suppose as your testing outside of the designed limits of what i assume is t+e but my post was in jest as we get our paperwork thrown back at us if we write “carried out megger testing on cables”
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Should be twice the nominal voltage, so in this case 500v
He said the current generated is 15mA, how can that damage the insulation of a 32A circuit?
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Your testing the insulation of the conductors, the rule of thumb is twice the working voltage so for 240v you insulation test at 500v, at 1000v your testing roughly 4 times the voltage the conductors are designed to carry so you can risk puncturing the insulation and actually causing a faliure i believe its called “treeing”
Im not saying it will happen im just saying it might, also the 32a mcb im assuming would be disconnected, you would just be testing the conductors.