Ireland Should I have voltage to my earth rod?

[Lignarius]

Hi, I bought a house which I renovated.
I stripped out all wiring, all of it.
new fuse board, 2 rcd, which I set as up stairs and down stairs. I’ve a ring for; sockets up, sockets down, kitchen white goods, kitchen sockets, lights up, lights down and a single cable to the boiler, one to the loft socket and one to the hob. All works no issues. I did work in the garden and had to move the earth rod i had installed. When disconnecting it I got quite a shock. I put the volt meter across it and got 135V ac. So I refitted the rod. Then disconnected it at the fuse board so I could put the volt meter between the rod and the each earth on the board. I got 2V from most but some read 45V, 90V, 50V & 90V (upstairs lights, downstairs lights, white goods, and hob) I killed the board while I reconnected everything then did a last check and now get a steady 35V to the earth rod after it was all off for 5mins. I understand you can have some earth leakage from some appliances but surely something is amis here? I had initially assumed it was a screw through a cable somewhere but it’s coming from 4 different circuits.
Any advice?

 

[Pete999]

Hi, I bought a house which I renovated.
I stripped out all wiring, all of it.
new fuse board, 2 rcd, which I set as up stairs and down stairs. I’ve a ring for; sockets up, sockets down, kitchen white goods, kitchen sockets, lights up, lights down and a single cable to the boiler, one to the loft socket and one to the hob. All works no issues. I did work in the garden and had to move the earth rod i had installed. When disconnecting it I got quite a shock. I put the volt meter across it and got 135V ac. So I refitted the rod. Then disconnected it at the fuse board so I could put the volt meter between the rod and the each earth on the board. I got 2V from most but some read 45V, 90V, 50V & 90V (upstairs lights, downstairs lights, white goods, and hob) I killed the board while I reconnected everything then did a last check and now get a steady 35V to the earth rod after it was all off for 5mins. I understand you can have some earth leakage from some appliances but surely something is amis here? I had initially assumed it was a screw through a cable somewhere but it’s coming from 4 different circuits.
Any advice?

That's one seriously dangerous CU (Fuseboard) you have there Mate!

 

[Lignarius]

That's one seriously dangerous CU (Fuseboard) you have there Mate!

In what way?

 

[Taylortwocities]

Our resident pet Irishspark @Risteard
will be along with a whole list of Irish regulations that will put you at risk of imprisonment for a very long time.
What a mess.

 

[goasis]

Someone's gotta ask it.... What testing did you do on your new install, apart from the fact that it works?

Also, what are you getting this voltage between? The disconnected rod and the installation earthing?

 

[westward10]

As in #4 only Registered Electrical Contractors can carry out the work you have described. To be honest I am surprised you are still alive.

 

[Lignarius]

Someone's gotta ask it.... What testing did you do on your new install, apart from the fact that it woks?

I don't know why I bothered to ask, no one ever answers a question.
No as of yet it is not tested, I was waiting to get my cousin over to test it but hey recent pandemic kinda delayed that a few months.

All i want to know is what would be causing voltage to my earth? I've identified it on 4 circuits, both lighting rings, the white goods ring and the hob, which is a straight cable from the board to the hob.

 

[Taylortwocities]

Your lighting circuits are wired as rings? That’s not at all usual. But I suppose you know what you are doing.

 

[Pete999]

In what way?

For one bare busbar two Busbar not fitted correctly

 

[Lignarius]

Your lighting circuits are wired as rings? That’s not at all usual. But I suppose you know what you are doing.

yes the lighting is wired as a ring to the ceiling roses, from there run the switch wires and lighting wires.

 

[snowhead]

To answer the question,
No there shouldn't be that voltage onto the rod.
There's a fault withint the electrical installation that needs finding and fixing.
Untill then turn everthing off.

 

[Lignarius]

Someone's gotta ask it.... What testing did you do on your new install, apart from the fact that it works?

Also, what are you getting this voltage between? The disconnected rod and the installation earthing?

I disconnected the earth rod at the board so i could put the volt meter across from the earths in the board (live) to the rod (neutral)
[automerge]1598360157[/automerge]

For one bare busbar two Busbar not fitted correctly

bus bars are not bare, I dropped the shroud for the picture.

 

[Pete999]

I disconnected the earth rod at the board so i could put the volt meter across from the earths in the board (live) to the rod (neutral)
[automerge]1598360157[/automerge]

bus bars are not bare, I dropped the shroud for the picture.

OK But if the power is on it's still dangerous

 

[Lignarius]

To answer the question,
No there shouldn't be that voltage onto the rod.
There's a fault withint the electrical installation that needs finding and fixing.
Untill then turn everthing off.

I appreciate you actual answer, I've identified faults in other properties in the past but I've not seen faults that change around like this making it hard to isolate a single damaged cable.
[automerge]1598360677[/automerge]

OK But if the power is on it's still dangerous

I only disconnected while i tested between each individual earth to the board so i could identify the fault source. i then reconnected so as to have earth protection. note the RCD's don't trip with the faults.

 

[Strima]

Without proper inspection and testing we cannot say why's there's voltage going to earth on your installation, there could be numerous reasons from appliance leakage to a neutral fault on the supply line. Remote diagnosis over the internet is next to impossible.

This is why we test before energising an installation.

Also we isolate the supply before removing the main earth as there's potential for voltage on the earth cable and risk of electric shock as you have found.

I would suggest you get your cousin to come over sooner rather than later to take a look assuming they're a registered electrician?

 

[Pete999]

For one bare busbar two Busbar not fitted correctly

You need to ensure that all the stubs on BB are located properly as well

 

[telectrix]

Hi, I bought a house which I renovated.
I stripped out all wiring, all of it.
new fuse board, 2 rcd, which I set as up stairs and down stairs. I’ve a ring for; sockets up, sockets down, kitchen white goods, kitchen sockets, lights up, lights down and a single cable to the boiler, one to the loft socket and one to the hob. All works no issues. I did work in the garden and had to move the earth rod i had installed. When disconnecting it I got quite a shock. I put the volt meter across it and got 135V ac. So I refitted the rod. Then disconnected it at the fuse board so I could put the volt meter between the rod and the each earth on the board. I got 2V from most but some read 45V, 90V, 50V & 90V (upstairs lights, downstairs lights, white goods, and hob) I killed the board while I reconnected everything then did a last check and now get a steady 35V to the earth rod after it was all off for 5mins. I understand you can have some earth leakage from some appliances but surely something is amis here? I had initially assumed it was a screw through a cable somewhere but it’s coming from 4 different circuits.
Any advice?

i hate spagetti, (and pasta, paella, fish, and mayonaise). your pic only qualifies for the first.

 

[davesparks]

All i want to know is what would be causing voltage to my earth? I've identified it on 4 circuits, both lighting rings, the white goods ring and the hob, which is a straight cable from the board to the hob.

Disconnecting any earth from an energised installation is a very dangerous thing to do, and will often result in apparently random voltages between the disconnected parts even in a perfectly safe installation.

Why on earth are the lighting circuits wired as a ring?

Instead of performing dangerous, and quite meaningless, tests that don't follow a logical fault finding process you should be testing in a logical manner.

First you need to establish whether or not there is actually anything wrong.
Measureing IR and earth leakage might help with this. Also assessing the loads for what earth leakage you might normally expect might help.

 

[Lignarius]

Without proper inspection and testing we cannot say why's there's voltage going to earth on your installation, there could be numerous reasons from appliance leakage to a neutral fault on the supply line. Remote diagnosis over the internet is next to impossible.

This is why we test before energising an installation.

Also we isolate the supply before removing the main earth as there's potential for voltage on the earth cable and risk of electric shock as you have found.

I would suggest you get your cousin to come over sooner rather than later to take a look assuming they're a registered electrician?

I appreciate the impossibility of remote diagnosis, I was just wondering if anyone had any ideas on what to check or look for, any common issues etc.

When i briefly disconnected the rod outside i was just moving it over while i had an excavator to pull it up. I hadn't anticipated there to be any voltage there or i would have cut it turned it off first. I then disconnected it at the board and turned the power on briefly while I put the volt meter across each earth individually. Then immediately reconnected

 

[Pete999]

I appreciate the impossibility of remote diagnosis, I was just wondering if anyone had any ideas on what to check or look for, any common issues etc.

When i briefly disconnected the rod outside i was just moving it over while i had an excavator to pull it up. I hadn't anticipated there to be any voltage there or i would have cut it turned it off first. I then disconnected it at the board and turned the power on briefly while I put the volt meter across each earth individually. Then immediately reconnected

Across each earth and what exactly

 

[telectrix]

possible N-E fault on the installation. only way to solve is with a MFT and a spark who knows how to interpret readings.

 

[UNG]

What type of volt meter are you using

 

[Lignarius]

Disconnecting any earth from an energised installation is a very dangerous thing to do, and will often result in apparently random voltages between the disconnected parts even in a perfectly safe installation.

Why on earth are the lighting circuits wired as a ring?

Instead of performing dangerous, and quite meaningless, tests that don't follow a logical fault finding process you should be testing in a logical manner.

First you need to establish whether or not there is actually anything wrong.
Measureing IR and earth leakage might help with this. Also assessing the loads for what earth leakage you might normally expect might help.

I appreciate the risk of disconnecting the earth however I was the only person at risk and was aware of what i was and was not touching.

The logical process was to establish which earth wire was the source of the live voltage, I had anticipated finding 1 then simply testing along the cable till I found the faulty section and then replace it.

 

[Lucien Nunes]

What you are measuring is probably perfectly normal. When the installation MET is disconnected from earth (in this case from the rod) there is no path for even the tiniest amount of normal leakage, therefore it raises the voltage of the installation earthing system in an attempt to get to earth. When the only path is through your voltmeter, it will register a voltage, but the actual voltage does not tell you much and does not represent a voltage that will occur in normal operation. It is as much an indication of the input resistance of your meter as it is of the amount of leakage. A voltmeter with 10 megohms input resistance will read 135V when there is just 135/10,000,000 = 13.5 microamps of leakage. A different meter will read a different voltage. Therefore this is a meaningless and misleading test.

Also. NEVER DISCONNECT THE MEANS OF EARTHING WITH THE INSTALLATION ENERGISED.

 

[Lignarius]

What type of volt meter are you using

Its a fluke 87 true RMS multimeter
[automerge]1598362191[/automerge]

What you are measuring is probably perfectly normal. When the installation MET is disconnected from earth (in this fromthe rod) there is no path for even the tiniest amount of normal leakage, therefore it raises the voltage of the installation earthing system in an attempt to get to earth. When the only path is through your voltmeter, it will register a voltage, but the actual voltage does not tell you much and does not represent a voltage that will occur in normal operation. Therefore this is a meaningless and misleading test.

Also. NEVER DISCONNECT THE MEANS OF EARTHING WITH THE INSTALLATION ENERGISED.

Thank you that is very helpful, i note when all is connected I get a steady 35V across the earth and the neutral

 

[goasis]

I don't know why I bothered to ask, no one ever answers a question.
No as of yet it is not tested, I was waiting to get my cousin over to test it but hey recent pandemic kinda delayed that a few months.

All i want to know is what would be causing voltage to my earth? I've identified it on 4 circuits, both lighting rings, the white goods ring and the hob, which is a straight cable from the board to the hob.

I'm not trying to be awkward, but if you'd installed and tested properly in the first place you may already know the answer to your own question. And you wouldn't have energised a potentially dangerous installation.

 

[Vortigern]

Maybe you have crossed your neutral with your earth at some points.

 

[Lignarius]

possible N-E fault on the installation. only way to solve is with a MFT and a spark who knows how to interpret readings.

OK thanks, i get 35V across E and N and i get 235V across E and L
[automerge]1598362645[/automerge]

Maybe you have crossed your neutral with your earth at some points.

I'm going to say I don't think so but seeing as i don't have an ego issue and I believe there is a fault somewhere, I will start the triple checking. As I said though, everything works as expected currently, i know that's not reliable but its usually a good indicator.
[automerge]1598362827[/automerge]

i hate spagetti, (and pasta, paella, fish, and mayonaise). your pic only qualifies for the first.

I love spaghetti, I'm with you on all the rest though.
I considered threading in every cable in a very coordinated fashion however i didn't see the point as its not a control board, its a house.

 

[telectrix]

read Lucien's post.you may not even have a fault at all. an analogue meter might confirm this. ( analogue being a moving coil pointer instead of the new fangled LCD garbage ). I could loan you my analogue voltmeter, manufactured in 1934, at a sensible hire cost. just needs this year's calibration next month to be sure it's as accurate as i'ts been for the last 86 years.. .

 

[Lignarius]

Maybe if you had done this legally and used a Registered Electrical Contractor you wouldn't be in this mess.

The last electrician I paid for left socket on a metal back box hanging suspended in a void behind the electric fire for it to plug in to. He mustn't of had a plastic one to hand or a drill or screws either.

I put in every cable so I know none were pulled or stretched, I made every connection so I could be sure they were all tightened just right, I cut every tail so they are not too short or too long. I spent my childhood being taught to build control panels for factories but seeing as I didn't want to be a sparks I didn't. I have minimal experience in domestic wiring but I'm not a total novice when it comes to making electrical connections.
[automerge]1598364177[/automerge]

read Lucien's post.you may not even have a fault at all. an analogue meter might confirm this. ( analogue being a moving coil pointer instead of the new fangled LCD garbage ). I could loan you my analogue voltmeter, manufactured in 1934, at a sensible hire cost. just needs this year's calibration next month to be sure it's as accurate as i'ts been for the last 86 years.. .

I used to have one, seeing as i had no use for it i let it go.

 

[telectrix]

The last electrician I paid for left socket on a metal back box hanging suspended in a void behind the electric fire for it to plug in to. He mustn't of had a plastic one to hand or a drill or screws either.

I put in every cable so I know none were pulled or stretched, I made every connection so I could be sure they were all tightened just right, I cut every tail so they are not too short or too long. I spent my childhood being taught to build control panels for factories but seeing as I didn't want to be a sparks I didn't. I have minimal experience in domestic wiring but I'm not a total novice when it comes to making electrical connections.
[automerge]1598364177[/automerge]


I used to have one, seeing as i had no use for it i let it go.

there's always a use for everything. even mothers-in-law.

 

[Risteard]

The installation probably isn't neutralised. Incidentally that is a UK-style DB and not configured to comply with the National Wiring Rules.

 

[davesparks]

I appreciate the risk of disconnecting the earth however I was the only person at risk and was aware of what i was and was not touching.

The logical process was to establish which earth wire was the source of the live voltage, I had anticipated finding 1 then simply testing along the cable till I found the faulty section and then replace it.

Being the only person at risk does not make it any better, that just implies that no one else was there to phone the ambulance when it knocks you out cold.

You clearly were not aware of what you were doing as you did not isolate the installation before disconnecting the earth rod.

That is not a logical fault finding process, that is looking for a fault based on an assumption that a fault is there, but not actually confirming that a fault exists to start with.

 

[snowhead]

there's always a use for everything. even mothers-in-law.

..................Door Stop ??

 

[Lignarius]

The installation probably isn't neutralised. Incidentally that is a UK-style DB and not configured to comply with the National Wiring Rules.

I had wondered if there would be a difference.
Could you clarify what you mean by neutralised?

 

[davesparks]

I had wondered if there would be a difference.
Could you clarify what you mean by neutralised?

Neutralising is one of the basic provisions for electrical safety in the Irish wiring regulations. It is the system by which a TNCS supply has it's PEN referenced to earth on the consumers side of the ownership boundary.

Unfortunately I don't know the details of the requirements to be able to explain it, I only know the general requirement for neutralising, purpose of it and theory behind it.

 

[Risteard]

Neutralising is one of the basic provisions for electrical safety in the Irish wiring regulations. It is the system by which a TNCS supply has it's PEN referenced to earth on the consumers side of the ownership boundary.

Unfortunately I don't know the details of the requirements to be able to explain it, I only know the general requirement for neutralising, purpose of it and theory behind it.

You've done well @davesparks - neutralising is where the DSO's PEN conductor is connected to the MET by the main protective conductor (also referred to as the neutralising link), which is subsequently connected to the Earth electrode via an Earthing conductor.

I've been at two properties in the last fortnight which weren't neutralised - both of them had been that way for years. One of them I was able to rectify as it had a new style cut-out whereby I could connect the conductor. The other had an old internal sealed meter (the DSO used to neutralise at the meter) and therefore required an emergency call to the ESB. They sorted it within a couple of hours after I fitted a main protective conductor ready to connect.

Almost all installations within the State are TN-C-S (although there are a very few TT installations left in rural areas - but practically none. Certainly much less than 1%).

I also don't see any main equipotential bonding present (although it's hard to be sure what's connected to what from a photo of course).

 

[richy3333]

Wow, just wow

 

[Lignarius]

You've done well @davesparks - neutralising is where the DSO's PEN conductor is connected to the MET by the main protective conductor (also referred to as the neutralising link), which is subsequently connected to the Earth electrode via an Earthing conductor.

I've been at two properties in the last fortnight which weren't neutralised - both of them had been that way for years. One of them I was able to rectify as it had a new style cut-out whereby I could connect the conductor. The other had an old internal sealed meter (the DSO used to neutralise at the meter) and therefore required an emergency call to the ESB. They sorted it within a couple of hours after I fitted a main protective conductor ready to connect.

Almost all installations within the State are TN-C-S (although there are a very few TT installations left in rural areas - but practically none. Certainly much less than 1%).

I also don't see any main equipotential bonding present (although it's hard to be sure what's connected to what from a photo of course).

Thanks for getting back to me, obviously this is beyond me but I'd like to understand so I can have it rectified.

Currently the meter only has 2 tails; the Live and the neutral, I have set up the board in the same way as the previous was, the only difference being it was earthed to the plumbing, as all my plumbing, sinks, baths, etc. are all plastic or composite, its also plastic out to the property boundary, I fitted an earth rod. from what you are describing you suggest my supply should be TN-C-S which if I have understood it the DSO neutral doubles as the earth ie the PEN? I do not have a neutralising link between the MET and the neutral or the meter, nor did the previous board which was retrofitted around 25 years ago.

Would this not effectively make the bonded metalwork in a house effectively the same as the neutral? I realise this should not be an issue as it is effectively earth but still.

Is the inclusion of a rod an issue or if it does need a neutralising link does the rod interfere or would it be permissible to retain as an added safety measure.

The Meter is 1956 its all sealed so would need ESB to do anything there. Its an overhead supply.

 

[davesparks]

You've done well @davesparks - neutralising is where the DSO's PEN conductor is connected to the MET by the main protective conductor (also referred to as the neutralising link), which is subsequently connected to the Earth electrode via an Earthing conductor.

I know more than I let on, I just didn't want to post something that leads to the OP having a go at anything else.

 

[Risteard]

I know more than I let on, I just didn't want to post something that leads to the OP having a go at anything else.

Hopefully I've not been too specific with my answer!
[automerge]1598473476[/automerge]

Thanks for getting back to me, obviously this is beyond me but I'd like to understand so I can have it rectified.

Without getting into specifics, the electrode (rod) is mandatory. You MUST have it. It's not optional. But the installation still MUST be neutralised. (Assuming it's not a TT installation - but I can nearly bet my savings that it isn't. TT installations are INCREDIBLY rare within the State and generally are older (or perhaps heritage) installations which haven't been upgraded. That said, even most ancient installations within rural areas (certainly most if not all of Donegal) are TN-C-S.)

I would suggest that you get a REC on board. You can find one on the RECI website at www.reci.ie or www.safeelectric.ie

I presume you are aware of the scope of Restricted Electric Works - it is a criminal offence for these to be carried out by anyone other than a Registered Electrical Contractor (REC).

What part of the country are you in?

 

[Lignarius]

Hopefully I've not been too specific with my answer!
[automerge]1598473476[/automerge]

Without getting into specifics, the electrode (rod) is mandatory. You MUST have it. It's not optional. But the installation still MUST be neutralised. (Assuming it's not a TT installation - but I can nearly bet my savings that it isn't. TT installations are INCREDIBLY rare within the State and generally are older (or perhaps heritage) installations which haven't been upgraded. That said, even most ancient installations within rural areas (certainly most if not all of Donegal) are TN-C-S.)

I would suggest that you get a REC on board. You can find one on the RECI website at www.reci.ie or www.safeelectric.ie

I presume you are aware of the scope of Restricted Electric Works - it is a criminal offence for these to be carried out by anyone other than a Registered Electrical Contractor (REC).

What part of the country are you in?

Hopefully I've not been too specific with my answer!
[automerge]1598473476[/automerge]

Without getting into specifics, the electrode (rod) is mandatory. You MUST have it. It's not optional. But the installation still MUST be neutralised. (Assuming it's not a TT installation - but I can nearly bet my savings that it isn't. TT installations are INCREDIBLY rare within the State and generally are older (or perhaps heritage) installations which haven't been upgraded. That said, even most ancient installations within rural areas (certainly most if not all of Donegal) are TN-C-S.)

I would suggest that you get a REC on board. You can find one on the RECI website at www.reci.ie or www.safeelectric.ie

I presume you are aware of the scope of Restricted Electric Works - it is a criminal offence for these to be carried out by anyone other than a Registered Electrical Contractor (REC).

What part of the country are you in?

Im in west Dublin.

I was planning to get a sparks to test and rectify anything thats needed. As I understood it I thought the legal aspect was limited to tampering with ESB equipment and breaking their seals.

Im from Donegal though, assuming from your post that your up that directIon.

 

[Risteard]

Im in west Dublin.

I was planning to get a sparks to test and rectify anything thats needed. As I understood it I thought the legal aspect was limited to tampering with ESB equipment and breaking their seals.

Im from Donegal though, assuming from your post that your up that directIon.

Yes I'm in Derry, although a significant proportion of my work (if not the majority) is in Donegal. I'm in Limerick today though doing some lighting maintenance for a retail outlet. Cork tomorrow, Dundrum (Dublin) on Friday.

Legally it's not simply tampering with ESB equipment - in fact almost all work within the private home is covered by Restricted Electrical Works. (Visit Electrical Services in Derry & Donegal - Walsh Electrical Services - https://www.walshelectrical.ie/electrical-services.html#restricted-works for further details.)

 

[Lignarius]

Yes I'm in Derry, although a significant proportion of my work (if not the majority) is in Donegal. I'm in Limerick today though doing some lighting maintenance for a retail outlet. Cork tomorrow, Dundrum (Dublin) on Friday.

Legally it's not simply tampering with ESB equipment - in fact almost all work within the private home is covered by Restricted Electrical Works. (Visit Electrical Services in Derry & Donegal - Walsh Electrical Services - https://www.walshelectrical.ie/electrical-services.html#restricted-works for further details.)

wow I’ve just been reading, it’s pretty much any domestic electrical work!
bit late now though!

Regarding immediate risk, the installation is earthed, all metallic components are bonded, the circuits are all fairly simple, connections are all good. I assume it’s safe while I await testing. It’s 9 simple circuits with appropriately sized breakers on 2 RCDs with a 2 pole isolation switch, Aside from neutralising and testing what am I likely to need an REC to do? What kind of cost would I expect to pay?

 

[Scifen]

Always thought my house back home was a TT earthing arrangement and not a TN-C-S didn't know the pen to Earth was on the owner side of installation, does this mean for every TN-C-S in Ireland needs an earth rod installed for neutralizing I always assumed it was a TT because of that. You Learn something new everyday learning this trade.

 

[pc1966]

TT installations are INCREDIBLY rare within the State and generally are older (or perhaps heritage) installations which haven't been upgraded. That said, even most ancient installations within rural areas (certainly most if not all of Donegal) are TN-C-S.)

Out of curiosity, is the TN-C-S more or less mandatory in the republic?

Here you would normally use the DNO (supplier) earth if, as mostly, they provide one. Generally we were mostly TN-S, but moving to TN-C-S whenever systems are replaced, etc. But you could decided you want TT and put in a rod and up-front RCD, etc.

Also do you have any issues with PEN open faults causing outdoor shock risk for car chargers, etc, or is the "every property must have Earth rods" policy doing enough to keep the stray volts down in the event of a DNO cable fault?