Dodgy earth… well no earth at all
- Thread starter Snakeinthegrass
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Actually it's possible you could have a certain amount of leakage from both if the earths are not connected to earth but commonly connected, if you're touching an appliance current could be sourced from any leakage sources present.
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If no earth then one would not get a shock anyway. It would need two faults to get a shock, one neutral to touchable metal, and one line to touchable metal, and it would need to be from same RCD.
In my house 16 RCD's so the chances of two faults from same RCD is slim.
From what you have said it does indeed need investigating in rapid fashion by a competent person and corrections, if any, addressing quickly.
Can I suggest that your local council environmental services might be the best approach and/or your DNO/Electric Supplier (they have the authority to disconnect the installation if considered dangerous, ordinary folks including electricians only have authority vested in them by the installation owner - that`s not to say that none of us would be a "Good Samaritan" and remove immediate danger ASAP.
If I were in your position I would persuade my family and all persons to leave immediately and not return until sorted.
Voltage Detector Pens are not a reliable way of proving safe or unsafe in any circumstances but from all you have said (including shocks) sets off a warning to all of us that something is very wrong here.
I have two major concerns 1/ Something appears very wrong and 2/ How was this allowed to happen and go unnoticed by a contractor apparently (was the contractor a fit and proper person to inspect, test, work on the installation) and preventing from ever happening again?
Just as an aside - A fully functioning RCD does not need an earth to enable it to trip, people and equipment often need an earth where relevant to reduce voltage difference to safer levels until that trip occurs.
Can I suggest that your local council environmental services might be the best approach and/or your DNO/Electric Supplier (they have the authority to disconnect the installation if considered dangerous, ordinary folks including electricians only have authority vested in them by the installation owner - that`s not to say that none of us would be a "Good Samaritan" and remove immediate danger ASAP.
If I were in your position I would persuade my family and all persons to leave immediately and not return until sorted.
Voltage Detector Pens are not a reliable way of proving safe or unsafe in any circumstances but from all you have said (including shocks) sets off a warning to all of us that something is very wrong here.
I have two major concerns 1/ Something appears very wrong and 2/ How was this allowed to happen and go unnoticed by a contractor apparently (was the contractor a fit and proper person to inspect, test, work on the installation) and preventing from ever happening again?
Just as an aside - A fully functioning RCD does not need an earth to enable it to trip, people and equipment often need an earth where relevant to reduce voltage difference to safer levels until that trip occurs.
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Ah, my bad. I misread it as does not throw...
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Glad to see @Snakeinthegrass is still with us. Hope he tells us the outcome.
What we hope is the leakage hits a point when it will trip the RCD before anyone touches anything. They can take 40 mS to trip, and when one gets a belt, that's a long time.
But even my house, the central heating is not RCD protected. I think, the instructions for the inverter are not too clear, it may have a 300 mA RCD fitted. I still will not allow the boiler man to service boiler without me being there, just in case.
That is a good point, however even with an RCD which is working A1, in a home where the earth bonding is correct, I found the hard way, when making a channel down a wall with two hack saw blades for a water supply to the fridge, one people don't keep to permitted zones with electrical cables, and two even if the RCD does trip, touching line can knock one out.
What we hope is the leakage hits a point when it will trip the RCD before anyone touches anything. They can take 40 mS to trip, and when one gets a belt, that's a long time.
But even my house, the central heating is not RCD protected. I think, the instructions for the inverter are not too clear, it may have a 300 mA RCD fitted. I still will not allow the boiler man to service boiler without me being there, just in case.
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Yep. I’m still here. So far the landlord has been responsive and the sockets in Question have been placed off limits and the microwave which seems to have gone leaky has gone to the tip. Was interested to learn about the old steel conduits in these systems being used as the cpc. Will update when I get a satisfactory result
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To test a socket for me is so easy,
I plug in, select loop, press button, and if 0.3 or less, I know it is OK, the pass mark for a ring final is 1.365Ω for a non RCD protected socket. My meter is for DIY and still cost around £75, it also tests the RCD, but to reset quite a walk so did not take a picture of that. A professionals meter would have another decimal point at least.
There are cheaper DIY testers, this one
at £43 will test radial circuits, seem to remember it passes at 1.8Ω which for a ring final is too high, it has an RCD test, but clearly can't tell you if it tripped at 40 mS.
This one
down to £7.60, but no loop or RCD test. It will still show no earth 
so it says, I used one with the caravan to ensure line and neutral correct way around when abroad, but not much else.
The problem is since electricians have the proper tools, they have no reason to use the cheap testers, so in real terms don't know how well they will find a fault. Mistakes corrected.
I plug in, select loop, press button, and if 0.3 or less, I know it is OK, the pass mark for a ring final is 1.365Ω for a non RCD protected socket. My meter is for DIY and still cost around £75, it also tests the RCD, but to reset quite a walk so did not take a picture of that. A professionals meter would have another decimal point at least.There are cheaper DIY testers, this one
This one
so it says, I used one with the caravan to ensure line and neutral correct way around when abroad, but not much else.The problem is since electricians have the proper tools, they have no reason to use the cheap testers, so in real terms don't know how well they will find a fault. Mistakes corrected.
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Not so much 'old'. Its still perfectly acceptable to use threaded steel conduit & trunking systems as the CPC even on new work (with certain provisos like link wires between socket boxes & socket fronts, as well as bridging straps across trunking joins & THREADed steel conduit not slip joints). This is seen far more in industrial/commercial work than domestic & I accept that many Contractors will chose to run an earth wire in the conduit along with L & N but its no more 'essential' than some Contractors choosing to run a separate CPC in parallel with a SWA cable.
As others have stated, the problem here is that the person who retrofitted that Consumer Unit into that enclosure didn't really understand what he was dealing with and, by not ensuring that he left the installation with a satisfactory earth (which also begs the question ... What testing did he perform & what else has he missed???), left the installation in a more unsafe condition than before he started!
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Lead covered cable had a few twists of wire wrap to give earth continuity via the lead/ aluminium sheathing, if you disturbed to old cables in a loft you could see the sparks sometimes 
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In the 80s, when I used to install galv conduit as the CPC, i had a high current test meter that would check all joints were well made. Any that were not, you would hear crackling.
If I remember correctly they sent 25A thru as the test current, bad joints were shown up but also the the fizz bang crackle had the tendency to weld the joint to such an extent that it actually had a tendency to cause a weld which might have caused a bit of continuity correction as a result.
I have not seen one for a while though. Ho happy days!
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Some sloppy sparks did just that, relied on the machine to make their bad joints good, not me.
I had my trusty set of Bush King spanners and Knipex pipe grips along with stocks, dies and the pipe bending gear.
But I was chatting online with a guy who said he was doing some tests prior to a board change in a house that had a solid screwed conduit install for the sockets.
The conduit was the CPC and of course there's no end to end in a circuit like that where the conduit is joined to a box buried in concrete, on top of which the new board is to be mounted. He was trying to decide the best way (without the test kit we used to have) of testing the integrity of the conduit joints round the circuit.
I think we decided to check all joints were mechanically sound, clean all the fixing screw threads out and fix an earth terminal to the all the boxes. None of them had any. Then of course, the usual dead and live testing.
543.2.7 and 543.2.9 (not sure if they are up to date) allow for conduit, trunking and SWA etc (IE earthing arrangements that are not in a ring) to be used for Ring Final circuits.
But it would be so much easier if we still had the old 25A high current testers. I got out of that kind of work. What happened to them?
I had my trusty set of Bush King spanners and Knipex pipe grips along with stocks, dies and the pipe bending gear.
No, not me.
But I was chatting online with a guy who said he was doing some tests prior to a board change in a house that had a solid screwed conduit install for the sockets.
The conduit was the CPC and of course there's no end to end in a circuit like that where the conduit is joined to a box buried in concrete, on top of which the new board is to be mounted. He was trying to decide the best way (without the test kit we used to have) of testing the integrity of the conduit joints round the circuit.
I think we decided to check all joints were mechanically sound, clean all the fixing screw threads out and fix an earth terminal to the all the boxes. None of them had any. Then of course, the usual dead and live testing.
543.2.7 and 543.2.9 (not sure if they are up to date) allow for conduit, trunking and SWA etc (IE earthing arrangements that are not in a ring) to be used for Ring Final circuits.
But it would be so much easier if we still had the old 25A high current testers. I got out of that kind of work. What happened to them?
As the tenant your Landlord is legally responsible to have EICR's undertaken and a copy given to the tenant.
Do you have a copy of the EICR?
BTW there is definitely a C2 in the picture you have posted
Do you have a copy of the EICR?
BTW there is definitely a C2 in the picture you have posted
I wouldn‘t have binned the microwave. Anything with mains filter capacitors inside will read voltage if not earthed and can give slight tingles if touched while also touching earthed objects. Sink and dishwasher is a fairly common combo.
I believe you can get modern upgrades for those old skeleton boards. Youtuber Delroy (Eastway Electrical) did one on camera a few years ago. I wouldn‘t recommend his videos as tutorials, mind you, but he lists the materials he used for the job.
I believe you can get modern upgrades for those old skeleton boards. Youtuber Delroy (Eastway Electrical) did one on camera a few years ago. I wouldn‘t recommend his videos as tutorials, mind you, but he lists the materials he used for the job.
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