dangers associated with wiring earth to neutral in the consumer unit?

[overflow99]

First time on here.... Looking for your thoughts on my situation plz. I've a small apartment in Spain and recently discovered there is no earth in the building, which I'm nervous about. Firstly I purchased individual socket rcd's and put one in all 12 sockets. Don't even know if this is giving me any extra protection or not. There is, what I assume, is an rcd on the consumer unit. I've employed the service of an expat spark, recommended by a friend. He has run an earth connection to all sockets, returning to the consumer unit. We had discussed putting in an earth rod tt connection when I was last in Spain, which I was happy about, although where we are is built on rock, but he said he had a machine to place the rods. Now, on my return, he said the job was complete. When I checked there is no earth rods installed. I opened the consumer unit and the newly installed earth wires have been terminated in the same terminal as Neutral. A masking tape sticker has been placed saying Pme Tierra. To me it feels like I'm swapping one potentially dangerous situation for another. Am I overreacting? Also, what is the situation regarding my socket rcd's and the rcd on the consumer unit, will they act to save me or my Mrs in all situations. I've used a socket tester, (UK 3pin through a Spanish adaptor), and when positive pin goes to positive in the socket, the rcd test does trip the switch. But, if I turn it the other way round, positive pin to negative in the socket the rcd test doesn't trip the rcd. Is that normal? I identified which pin socket carries live and neutral btw so I can plug my UK items in the correct way round. Don't know if it makes a difference. Was going to ask him to put the originally agreed earth rods in, which would be just 6ft below our balcony to street level, but don't want to be that pain in the --- customer, if all is safe, as he seems a nice enough guy. Any thoughts on the safety aspect would be appreciated as I always like things done 100% right. Thanks in advance.

 

[overflow99]

Even thoughts on any part of the post would be appreciated. Thank you.

 

[littlespark]

The earth wire looks like its been connected to a live cable, not a neutral.

Do you have another photograph showing the straight on view, but with covers off? So we can see how the breakers are connected.

And give us a description of what each breaker switch does... (is one a mainswitch, controlling everything, and the others go out to circuits)

 

[overflow99]

The earth wire looks like its been connected to a live cable, not a neutral.

Do you have another photograph showing the straight on view, but with covers off? So we can see how the breakers are connected.

And give us a description of what each breaker switch does... (is one a mainswitch, controlling everything, and the others go out to circuits)

Thanks for your reply, appreciated littlespark. I've attached another couple of photos. 2 cables come in, a blue and a black from the mains. The other day a I put the multimeter across them and there was no voltage on the brown, but will recheck. In Spain there doesn't seem to be any adherence to colour codes.

 

[littlespark]

Looks to me like the supply in is the black and blue cables coming in from bottom right....
They go up to a double pole circuit breaker (20A) at the top, that then feeds the 25A RCCB below it.
Then goes through a 15A circuit breaker, and this exits through the back of the box. (only one circuit?)

I dont think theres much any of us UK based electricians can say about this... without knowing the regs....although i think one or two might have experience on spanish soil.

Im surprised the sockets are marked positive and negative.... thought they would be L and N

 

[overflow99]

Thanks for your reply, appreciated littlespark. I've attached another couple of photos. 2 cables come in, a blue and a black from the mains. The other day a I put the multimeter across them and there was no voltage on the brown, but will recheck. In Spain there doesn't seem to be any adherence to colour codes.

OK been checking with the multimeter. Firstly, all switches turn the electricity off. This is only a very small studio, with no bedrooms btw. The wires that come in the bottom are blue and black and arrive at the consumer unit via conduit from a dodgy look switch which is stuck behind a cupboard and says Main switch written on masking tape. The on off function of the dodgy looking switch does nothing. The black wire goes to the top left and the blue to the 2nd top left of the 3 +rcd switch terminal. Behind the single switch there is an exit point in the wall for the blue and brown wire. When bridging across from left to right on all switches there is zero V value. The top 2 switches can not work independently of one another. When bridging side by side going from left side or right side going down all show around 238V. When I turn the bottom single switch off and bridge across left, (where the earth wire is), to right it shows 230V but when switched on 0V. That's with the 4 above still in the on position. When they are off the value is also 0V on the single switch. Bridging across from left to right on the Rcd shows 9V when tripped and with the top 2 switches in the on position, even though electric is tripped off. The top 2 when off shows zero V. I bridged from the earth point at the brown wire to the earth connector in the round terminal box and it showed 0V. I'm pretty much at the limit of what I know electrically. Wondering about the safety implications of this set up, as will the rcd trip etc or even though we're on rock is TT viable /preferable, thanks.

 

[overflow99]

Looks to me like the supply in is the black and blue cables coming in from bottom right....
They go up to a double pole circuit breaker (20A) at the top, that then feeds the 25A RCCB below it.
Then goes through a 15A circuit breaker, and this exits through the back of the box. (only one circuit?)

I dont think theres much any of us UK based electricians can say about this... without knowing the regs....although i think one or two might have experience on spanish soil.

Im surprised the sockets are marked positive and negative.... thought they would be L and N

I think your path description sounds spot on and now I can visualise the path, thank you. I'm still puzzled about the earth wire joined with the brown wire. That earth wire goes straight up to the round junction box shown in the original post to join with all the earth wires coming from the sockets. What is being achieved here by doing this... I've attached another photo. Thanks.

 

[brianmoooore]

First of all, deriving a property's 'earth' terminal by connecting it to the incoming neutral supply wire is very common in the UK, and is known as PME or TNC-S, but this earthing terminal is provided by the supplying authority, subject to conditions, and relies on the incoming neutral being connected to an effective earth rod at the sub station and points in between.
I don't know the legality of an electrician making this connection himself where you are, but it appears that either he's strapped the earth to the incoming live (which isn't good) or the incoming polarity is wrong, and you have a single pole MCB connected in the neutral wire, which is also not good for other reasons.

 

[westward10]

I very much doubt we are going to be able to give a reasoned answer. Without being there and knowing the way things are done in Spain it is impossible to say.

 

[overflow99]

First of all, deriving a property's 'earth' terminal by connecting it to the incoming neutral supply wire is very common in the UK, and is known as PME or TNC-S, but this earthing terminal is provided by the supplying authority, subject to conditions, and relies on the incoming neutral being connected to an effective earth rod at the sub station and points in between.
I don't know the legality of an electrician making this connection himself where you are, but it appears that either he's strapped the earth to the incoming live (which isn't good) or the incoming polarity is wrong, and you have a single pole MCB connected in the neutral wire, which is also not good for other reasons.

Thanks for your reply Brian... I had read about PME TN-C-S and understood it's achieved by combining earth to neutral, which works well unless a break develops on the neutral return line then there could be problems with things going live or getting zapped. If the earth is tied to live that would be worse I'd imagine. When I check at the sockets Neutral to Earth shows 0V and Live to Earth 230V and Live to Neutral 230V. Which scenario would this indicate... Earth to Live connection or Earth to Neutral connection? Or could it be either? If the connection has been made on a self basis rather than approved by the the supply company is there any extra implication other than administrative and as the end user what do I need to watch for... Are rcd's going to work. Again appreciate your reply.

 

[overflow99]

I very much doubt we are going to be able to give a reasoned answer. Without being there and knowing the way things are done in Spain it is impossible to say.

Agreed... It's difficult to describe and show you and a different country's regs all adds to the difficulty.... Thank you

 

[overflow99]

I suppose if I boil it down, will rcd's protect us should things go bad or do I ask for TT supply, which may be hard to achieve on this rocky area .... Don't want to fry the wife, ( atm anyway ), or granddaughter... Thank you all, for your help

 

[Mike Johnson]

Getting a TT spike into rocky ground was nearly always overcome with a plate electrode the main problem was then getting two or three testing spike's into the ground for verifying Ω reading that aside putting the plate near a tree helped or even driving a spike with an SDS near a tree, necessity being the mother of invention.

Convention in the EU is that looking straight on at a socket face plate, phase should be on the right additionally all MCB's should be dual pole.

 

[pirate]

I have some experience with Spanish electrics. Some stuff is just awful...and some is very good indeed.
My advice is simply that you employ a Spanish electrician from a reputable company and have him/her check your system completely for safety. This is unlikely to be expensive because it's a small system and, from my personal experience, Spanish electricians are not expensive, having an hourly rate quite a bit lower than many in the UK.
Clearly you are concerned about this, rightly so, thus a proper check is essential. As I said, the cost will be reasonable, and the safety and peace of mind do not have a cost.

 

[overflow99]

Getting a TT spike into rocky ground was nearly always overcome with a plate electrode the main problem was then getting two or three testing spike's into the ground for verifying Ω reading that aside putting the plate near a tree helped or even driving a spike with an SDS near a tree, necessity being the mother of invention.

Convention in the EU is that looking straight on at a socket face plate, phase should be on the right additionally all MCB's should be dual pole.

Thanks Mike for your reply and info on the plate electrode, which may be the way to go. I've pushed the building administrator on getting an earth connection for the community but without success, which is why I got a spark in, as thought I'll get it done myself. Not sure I'm sleeping easier though.

 

[overflow99]

I have some experience with Spanish electrics. Some stuff is just awful...and some is very good indeed.
My advice is simply that you employ a Spanish electrician from a reputable company and have him/her check your system completely for safety. This is unlikely to be expensive because it's a small system and, from my personal experience, Spanish electricians are not expensive, having an hourly rate quite a bit lower than many in the UK.
Clearly you are concerned about this, rightly so, thus a proper check is essential. As I said, the cost will be reasonable, and the safety and peace of mind do not have a cost.

Thanks Pirate for your reply and advice. Totally agree on the peace of mind aspect, which is why I wasn't happy having no earth in place. I'm going to give the administrators/community of owners another push about a community earthing point. So far there's been a couldn't care less attitude to this crazy foreigner looking something as innovative as being safe in your own home. Failing that I'll take the advice offered here, as really don't want anyone hurt due to my laziness. Thanks again!

 

[Mike Johnson]

The problem you will have with the lay people on the management committee is trying to explain that an RCD will not work effectively without a compliant earth, therefore opening up the possibility of electrocution (death), the problem is do they know what an RCD does.

 

[OnlQQker]

Might be worth a read OP..

It wont let me post the link so search

TT Earth Spike Installation questions​

There is something similar posted on engx.------.org

From 2020

 

[overflow99]

The problem you will have with the lay people on the management committee is trying to explain that an RCD will not work effectively without a compliant earth, therefore opening up the possibility of electrocution (death), the problem is do they know what an RCD does.

They look marginally interested for a moment, then shrug their shoulders.... Think as it's been like this for years

The problem you will have with the lay people on the management committee is trying to explain that an RCD will not work effectively without a compliant earth, therefore opening up the possibility of electrocution (death), the problem is do they know what an RCD does.

Think they're interested for a moment then shrug the shoulders... It's been like this for years and no ones got hurt is the predominant attitude...

 

[overflow99]

Might be worth a read OP..

Earth Rod

Might be worth a read OP..

It wont let me post the link so search

TT Earth Spike Installation questions​

There is something similar posted on engx.------.org

From 2020

Thanks will check it out when home later

 

[Mike Johnson]

Things move on, the latest in France is electrocution by using a mobile phone and charger in a bathroom, girl in bath electrocuted, father went in to save her and was also electrocuted, a correctly functioning RCD would have saved both of them.

 

[overflow99]

Things move on, the latest in France is electrocution by using a mobile phone and charger in a bathroom, girl in bath electrocuted, father went in to save her and was also electrocuted, a correctly functioning RCD would have saved both of them.

Sad indeed... A pet hate of mine, are the hand dryers blowing water all over an electrical socket below it, with you standing on the wet patch on the floor.

 

[Mike Johnson]

I don't know the legal regulations in Spain with regards to "duty of care", "corporate manslaughter" or even "Health and Safety" but they would come under the EU Regulations, you would need to look them up.

 

[Simon47]

As Mike hints at, if the management are aware of a danger and do nothing to mitigate it then they could be in deep trouble if something happens. If you are into theatrics you could try sonething like "So Mr X, you're stood in the dock and the prosecution asks why you did nothing about the safety issue reported - could you explain to the court why you let little <insert name of young child> be electrocuted for lack of any action ?"
Then follow up by listing possible prison sentences for things like manslaughter by gross negligence - whatever the law has over there. A realisation of serious potential consequences tends to concentrate minds.

But back to what your electrician has done ...
He's done a DIY attempt at TN-C-S for earthing which is normally only done along with PME (protective multiple earthing) - which are separate things.
In the UK, TN-C-S is only done by the DNO (distribution network operator) when they also have PME.
PME means that there are multiple points where the CNE (combined neutral & earth, akso known as PEN, protective earth and neutral) conductor is earthed. Thus is done to minimise the risks inherent in the earthing system - notably that a broken CNE can result in all your "earthed" equipment casings etc. becoming live.
Unless the electrician has positive confirmation of the presence of the multiple earthing points then what the has done is not PME and has introduced a significant rusk to try and mitigate a different risk. Notably, RCDs provide no protection againt a broken CNE fault.

 

[brianmoooore]

- notably that a broken CNE can result in all your "earthed" equipment casings etc. becoming live.

The "all" here is important. TNC-S regs on the consumer side of the installation, in the UK, are intended to ensure that ALL metal in reach that could have a relatively low resistance to earth is indeed dragged up to near the live voltage. The idea being, that like the bird perching unharmed on live overhead wires, if you touch 'live' metal with one hand and near equally 'live' metal with the other, you will not be electrocuted.

 

[overflow99]

I don't know the legal regulations in Spain with regards to "duty of care", "corporate manslaughter" or even "Health and Safety" but they would come under the EU Regulations, you would need to look them up.

I have tried putting the hard push on the administrators insinuating that not reacting to a serious problem with a serious incident such as the building burning down isn't going to be a good look.... Followed by, from my point of view, I don't want my granddaughter or wife injured or killed, which is why I'm being a pain, but nothing personal, against them.... They stopped replying to my emails.... Written evidence of ineptitude isn't a good look either I suppose.

I don't know the legal regulations in Spain with regards to "duty of care", "corporate manslaughter" or even "Health and Safety" but they would come under the EU Regulations, you would need to look them up.

 

[overflow99]

As Mike hints at, if the management are aware of a danger and do nothing to mitigate it then they could be in deep trouble if something happens. If you are into theatrics you could try sonething like "So Mr X, you're stood in the dock and the prosecution asks why you did nothing about the safety issue reported - could you explain to the court why you let little <insert name of young child> be electrocuted for lack of any action ?"
Then follow up by listing possible prison sentences for things like manslaughter by gross negligence - whatever the law has over there. A realisation of serious potential consequences tends to concentrate minds.

But back to what your electrician has done ...
He's done a DIY attempt at TN-C-S for earthing which is normally only done along with PME (protective multiple earthing) - which are separate things.
In the UK, TN-C-S is only done by the DNO (distribution network operator) when they also have PME.
PME means that there are multiple points where the CNE (combined neutral & earth, akso known as PEN, protective earth and neutral) conductor is earthed. Thus is done to minimise the risks inherent in the earthing system - notably that a broken CNE can result in all your "earthed" equipment casings etc. becoming live.
Unless the electrician has positive confirmation of the presence of the multiple earthing points then what the has done is not PME and has introduced a significant rusk to try and mitigate a different risk. Notably, RCDs provide no protection againt a broken CNE fault.

Thanks Simon, yes tried putting pressure on the building administrators. They stopped replying to emails but I started with the emails again last few days but with innocuous non earthing enquiries and they replied. Asked about the earthing again yesterday, did get a reply from a Secretary saying they would ask the Administrator and get back to me but again no reply today. In relation to the wiring in my apartment I've been googling in English and Spanish about joining earth to neutral as a means of creating an earth. I can't find anything where it is a method of earthing in Spain except for an individual saying he had done it this way in his own apartment. I did read somewhere that the lines are earthed every 500m on the way back to the substation. When I was using the socket tester the rcd test trip worked when orientated positive plug pin to positive socket recepticle but when turned upside down positive in to socket neutral it wouldn't trip. Is that what you mean by rcd not offering protection? In my mind that's a scenario where a tree brings down a neutral line in a storm or am I off the mark? Thanks again for your input!

 

[overflow99]

The "all" here is important. TNC-S regs on the consumer side of the installation, in the UK, are intended to ensure that ALL metal in reach that could have a relatively low resistance to earth is indeed dragged up to near the live voltage. The idea being, that like the bird perching unharmed on live overhead wires, if you touch 'live' metal with one hand and near equally 'live' metal with the other, you will not be electrocuted.

Thanks again Brian... In a scenario where my hand is on the fridge or I'm in the shower with the water heater on because my apartment is on rock am I going to likely get killed if a neutral break occurs or feel a tingle or worse. Or what us my biggest concern? thanks

 

[Mike Johnson]

When I was using the socket tester the rcd test trip worked when orientated positive plug pin to positive socket recepticle but when turned upside down positive in to socket neutral it wouldn't trip. Is that what you mean by rcd not offering protection? In my mind that's a scenario where a tree brings down a neutral line in a storm or am I off the mark? Thanks again for your input!

Most socket testers are only a device that short out between phase and earth, therefore orientating the tester to short out between earth and neutral would have no effect as they are already connected.

I did read somewhere that the lines are earthed every 500m on the way back to the substation

A tree bringing down an overhead neutral line would have to be within 500M of your property to have any detrimental effect on your supply.

 

[Mike Johnson]

Someone (individual) within the administration is responsible for H&S ask them who that is? you already have written evidence that they have been informed of a potentially serious omission to the electrical installation it is therefore they who will have to stand up in court and answer the question of why this issue was not addressed if someone is killed due to its omission.

 

[Simon47]

The "all" here is important. TNC-S regs on the consumer side of the installation, in the UK, are intended to ensure that ALL metal in reach that could have a relatively low resistance to earth is indeed dragged up to near the live voltage. The idea being, that like the bird perching unharmed on live overhead wires, if you touch 'live' metal with one hand and near equally 'live' metal with the other, you will not be electrocuted.

A tree bringing down an overhead neutral line would have to be within 500M of your property to have any detrimental effect on your supply.

But this is assuming that all extraneous conductive parts are in fact well bonded. Given what we know about Spanish electrics, I would not assume this to be the case.

EDIT: In fact, go back to the OPs pictures and tell me where you see evidence of ANY equipotential bonding at all.

 

[overflow99]

Most socket testers are only a device that short out between phase and earth, therefore orientating the tester to short out between earth and neutral would have no effect as they are already connected.

A tree bringing down an overhead neutral line would have to be within 500M of your property to have any detrimental effect on your supply.

Thanks for clarifying, much appreciated. GOOD NEWS.... Pester power has finally worked... I got an email this morning from the Community Administrator saying they had appointed an electrician to put in a central earthing point and they would be looking to find a suitable place to position the earth connector and they will bring it to the meter board. It would then be up to me to have the earth brought from the meter board to the apartment. Very relieved, if not very surprised. So one last question, when the earth enters my apartment should I have them untie earth and neutral and just link to the new earth connection or leave them joined. My thoughts as a layman is untie, would this be right. Though I think if their electrician, (Spanish), does, bring the connection up for me, he might look a little surprised to see it. Thanks to everyone who assisted me over the last number of days - totally appreciated!

 

[overflow99]

Looks to me like the supply in is the black and blue cables coming in from bottom right....
They go up to a double pole circuit breaker (20A) at the top, that then feeds the 25A RCCB below it.
Then goes through a 15A circuit breaker, and this exits through the back of the box. (only one circuit?)

I dont think theres much any of us UK based electricians can say about this... without knowing the regs....although i think one or two might have experience on spanish soil.

Im surprised the sockets are marked positive and negative.... thought they would be L and N

Hi littlespark, the 15amp circuit breaker at the bottom has troubled me, since you mentioned it being live. So, I switched ONLY the 15amp breaker off and I'm still getting 230v at the socket L to E. Is the MCB not wired the wrong way round. The live with the earth tied to it, goes out through the wall to the to the sockets btw. The spark told me when paying him last night the earth was tied to neutral. But surely that is tied to the L as you pointed out. When the breaker was off there was an 8v reading in the sockets L to N, I should also say.

 

[overflow99]

Looks to me like the supply in is the black and blue cables coming in from bottom right....
They go up to a double pole circuit breaker (20A) at the top, that then feeds the 25A RCCB below it.
Then goes through a 15A circuit breaker, and this exits through the back of the box. (only one circuit?)

I dont think theres much any of us UK based electricians can say about this... without knowing the regs....although i think one or two might have experience on spanish soil.

Im surprised the sockets are marked positive and negative.... thought they would be L and N

I opened up the CU again and the round junction box above and what I found was the blue and brown wires coming in from the wall just above the 15a circuit breaker are actually the L & N coming in to the CU. The black and blue wires are leaving the CU to the dodgy looking wall switch marked Main Switch. The wire colours are the wrong way, not to code. The brown wires and therefore the black wires are N and the blue wires are L, which I think explains why I was getting 230v L to N when only that 15a circuit breaker was switched off. The neutral is going through the circuit breaker and the E is tied to N at the point of entry. The way I checked L and N, was multimeter from brown wire to E, connector in the round junction box, (0v), and blue wire to E in the junction box, (230v). So the direction seems to be incoming brown N to 15a circuit breaker, outgoing brown N from 15a circuit breaker to RCD top right ON position. Outgoing brown N from RCD to top right ON position of double pole 20a circuit breaker, exiting 20a circuit breaker by black N and leaves CU at the bottom and goes to dodgy looking wall switch, marked Main Switch. The incoming blue L comes out of the wall and goes to the bottom right ON position on the RCD and blue L wire exits RCD and goes to bottom right ON position of the 20a Double Pole Circuit Breaker. Blue L wire exits 20a circuit breaker and leaves CU at the bottom and goes to dodgy looking wall socket marked Main Switch. E joins incoming N at the 15a circuit breaker and joins the E from the sockets in the round junction box above. Why would Neutral go through the 15a circuit breaker, as I found out switching it off didn't interrupt the supply. Would this not trip in the event of a fault or are the RCD and 20a double pole doing that job. Is it safe set up bar the concerns of a N break, (which I'm definitely not dismissing). There's no other immediate in apartment safety issue is what I'm wondering. If it was your CU, what would be the safest wiring approach, thanks.