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[SOLVED] Mains leaking currents causing problems in my house

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eagle1109

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Hi,

Now I wanna know why the mains has leaking currents? Checking the house's wall plugs, there are no grounding system so it's only L & N lines.

First I get small to medium electric shocks from the dish washer machine.

I also get electric shocks on my PC rig !! I didn't connect that to the fact that the house isn't grounded, so the shock I get from PC case means that absence of grounding system is the problem !! I thought that the power supply is the problem.


I bought a new PSU and installed it this morning but the same problem still exist !!! Now it's for sure the mains problem. I lost a 780 classified GPU that costed me around $400 and bought a new GPU for $470 and thought the PSU is the problem so I bought a new PSU for $125 !!

What should I do now ?? I think the best solution is to call an electrician and tell him to install a grounding system.

But guys what if that is not possible ? What if the person who managed the building process didn't actually prepare a grounding rode and cabling to the main panels to each apartment ?

Is there something I can do in case if wiring a grounding system isn't possible ?

Also I have a question, Why these leaking currents exist ?
 

How about this one:

It's suitable for our V/Hz in Saudi Arabia.

**broken link removed**
 

eagle 1109, when you get an electric shock it means your body is touching TWO points with a voltage between them. The shock is the resistance of your body passing current between the different potentials. It may not be necessary to rewire the house if you can identify the points you are connected to and bond them together. It would not remove the absolute voltage but the difference would be reduced or eliminated.

See if you can find the other connection point, it is probably through your feet, even if wearing shoes, down to the floor. If it is, an anti-static mat (or a static dissipative mat) on the floor and bonded to the PC case may be all you need.

Note that the interference filters at the input to the PC power supply will almost certainly cause the case to rise in voltage if it has no earth connection. This is quite normal but in almost every situation the wall socket has an Earth pin the voltage can discharge to.

Brian.
 
Here in the US, house wiring once had 2 wires only. I saw appliances that gave me a shock if I touched them and a metal faucet simultaneously. Or if I was barefoot on wet ground.

The shock stopped if I reversed the plug in the wall receptacle. (We didn't have 3-prong plugs yet.) This told me the chassis was connected through some amount of resistance to internal electrical wiring.

Usually the shocks were startling but not dangerous. I once did a test hooking up a light bulb between a chassis and faucet (or radiator, etc.). The bulb didn't light. Therefore current is low. Nevertheless my meter showed 120VAC. It became 0V when I reversed the plug.

I found I had to pay attention to orientation of the plug, with appliances with a metal housing, and when hooking up audio equipment.

Try doing similar tests in your house.
 
Hi all,

Thank you very much for the replies.

I work in a technical college. I asked a student as I'm a noob trainer who really don't understand much in this life :) about the grounding system in this city and he told me that he also lost a PC PSU and he had to wire a cable from the main panel neutral to his socket and earth that.

Also a colleague today told me that I just have to connect the third wire in the socket that is meant to be an earth to the neutral of the main panel !!

I really didn't understand that and I told him .. why ?? The neutral is the back way of the AC current !! How should I ground my socket to the other line of the mains voltage.


He explained to me types of grounding system, and the voltage that is coming to house main is 3 phase !! I didn't understand that !! how it's a 3-ph and I power my appliances with 1-ph ?!

When you want to get 1-ph out of 3-ph signal, you need a special transformer or something similar. But he kept explaining that we get the 3-ph star configuration of voltage coming from electricity company, and the electrician just give me 2 lines of any 2 phase to get 220V, and when they want to provide 110V, they just take one wire from L1 and another from the neutral and that's it.

How about that guys ?

So anyway I took pictures of the mains panel this afternoon:

This is the mains panel

20190930_171549.jpg


Here I was wondering why, there are 3 wires going together?

20190930_172015.jpg


This is the socket in the room I'm plugging my stuff to .. he's paralleling things out and there's no ground and also there're no distribution points in the room in case I want to add something, so I guess the wires are coming directly from the main panel.

20190930_181803.jpg
 

The mains panel appears to be three phase but I'm not sure where the incoming yellow wire goes to, presumably it links to some of the breakers underneath. As I see it, there are four wires arriving, red, yellow and blue are the three phases and the think black cable is Neutral. The neutral bus bar (linking bar) is the bare metal bar with screw terminals on the right side. The equivalent on the left side would be for linking the Earth connections if they existed. Three phases are only needed for some motor applications, no domestic equipment uses them. When a single phase is needed, it is derived from one of the phases and neutral. I think in your mains panel there are two phases leaving the box but only one arriving at the sockets you show. In some countries, particularly where mains is 110V, two phases are distributed to some sockets so you can get a higher voltage across the phases instead of using neutral, I'm not sure what the system is in your country.

Neutral and Earth are often joined back at the distribution point but usually there is also a good real 'planet' Earth connection at the same point. The idea is that the live (line) and neutral wires carry the working current but the earth does not and remains essentiall at the same potential as the ground beneath your feet, even if a fault occurs and raises the neutral wire to higher voltage.

Brian.
 
eagle 1109, when you get an electric shock it means your body is touching TWO points with a voltage between them. The shock is the resistance of your body passing current between the different potentials.

Yep, there must be a potential from the case that is +10V through my body that could like 1k ohm to the floor which is the lower potential, so yeah I'm a path for currents. And also the case actually is under stress the whole time, that led to me losing that GPU. Also the new one when I touched it from the back plate, there was a significant shock that is more powerful than the ones I get from the edges of the case. That time I immateriality switched off the PC and took out the GPU.





It may not be necessary to rewire the house if you can identify the points you are connected to and bond them together. It would not remove the absolute voltage but the difference would be reduced or eliminated.

I don't think I can rewire the house since the apartment is in rent system, so it's not mine. But anything I would do, should not be a bad thing for the owner as I would fix or enhance something for the next people that would rent the apartment after me.

But I didn't understand what you mean by identifying the points ? What points you mean ? And how to bond them ? I think I heard something similar today, that the colleague told me to connect something to the neutral. But didn't get it clearly.


See if you can find the other connection point, it is probably through your feet, even if wearing shoes, down to the floor. If it is, an anti-static mat (or a static dissipative mat) on the floor and bonded to the PC case may be all you need.

Of course if I wear my slippers, there won't be any shocks but, my way to test the leaks, is by removing the slippers, and just be bare feet on the floor, then I go and touch any part of the PC case.

Everything is on a ceramic floor, I don't know if that's a problem.

Do you want me to lift the PC on a cardboard or a wood table ? But I don't thing that would take the PC out of leaks stress.


Note that the interference filters at the input to the PC power supply will almost certainly cause the case to rise in voltage if it has no earth connection. This is quite normal but in almost every situation the wall socket has an Earth pin the voltage can discharge to.

Yep I think that's the problem, because there's no earth and there's something leaking in the house the filters trying to step off the leaks out of the PSU, by securing the PSU internals but putting anything else near to it under the redirected leaks .. it's my conclusion based on your statement I hope it's something near to be reasonable or logical.


Here in the US, house wiring once had 2 wires only. I saw appliances that gave me a shock if I touched them and a metal faucet simultaneously. Or if I was barefoot on wet ground.



The shock stopped if I reversed the plug in the wall receptacle. (We didn't have 3-prong plugs yet.) This told me the chassis was connected through some amount of resistance to internal electrical wiring.

Do you think that would work with me ?? The PSU and the cables strip are 3-prong plugs, so I can't switch them, but I think I can switch the cables coming from the main panel by opening the sockets, and switch the wires although they both are blue wire, so I don't know if switching them would fix the problem, because as the pictures in the last post the main panel has 3-ph wiring system.



Here is a 220v variant

https://www.amazon.com/dp/B013WWKQV0

its very useful as it detects very common issues, your linked product should work fine also.

OK, thanks but for now I think it's clear that the main problem now is that there is no earthing wires.
 

The interesting detail in the mains panel is the unused "E" (earth) terminal strip on the left side. It clarifies that protective earth is basically known in your country, but apparently unused in your house. I don't recognize a protective earth or ground wire, only black neutral distributed by the isolated terminal strip on the right.

The problem is that standard desktop PSUs are designed for protective earth connection and can't be safely operated without.
 
Wouldn't a buried pipe bonded to PSU chassis be adaquate to resolve his issue?
 
Last edited:

Although the black neutral wire may provide reliable earth potential, you can't trust it, particularly considering the general installation quality. And you still need a dedicated earth wire between panel and socket. I would rather install a separate earth wire to a metallic water pipe, if available.
 
I'm with FvM on this, without a protective Earth on the PC chassis it would adopt roughly half AC voltage simply because the input mains filter will have approximately the same value capacitors between chassis and neutral and chassis and live. Only a relatively small current will be available which is why you get a shock and not instant death!

If you can connect to a good 'real' Earth, preferably using a copper rod or pipe buried as deep as possible in the ground it will remove the problem. How you physically connect it to the wall sockets is a different matter. In most countries it is standard to run a three conductor cable around the house, live, neutral and Earth. It find it surprising that in what looks to be a recently wired house, it wasn't done that way during the build. Be careful if you connect to copper water pipes, they may change to plastic before going underground.

How effective the ground rod/pipe is will depend on the conductivity of the ground, if you are in a very dry area where conduction is poor, you need a longer rod/pipe or to bury several, spaced apart as far as possible with a thick wire linking them all together.

Brian.
 

By missing earth wiring, your house installation isn't build according to todays safety rules and not suited to supply power equipment with three pin power connector.

That's really dangerous with applicances like dish washers, because they have relative large leakage currents even in healthy state and likely fail with ground short.

"Dry" equipment like desktop PCs have normally lower leakage. Thus I wonder if your PC PSU either exposes a ground short or if you have inadvertently increased the leakage by parallel connecting the PC earth wire with that of other applicances?

If it's not an option to get proper earth wiring in your house, the panel should be at least supplemented by a sensitive three phase RCD to protect against letal electrical shocks. Or use individual RCD adapters for the most critical applicances.
 

Whoever designed that panel should be found accountable in case of fire caused by inadequate circuit breakers.
32A breakers are way to much for your wires that are connected to their outputs.
I can't see the rating of the 3 phase breaker, but I guess that that one is also overrated.

Lack of protective earthing is of a big concern, as well as lack of GFIs on kitchen and bathroom circuits (and GFIs need protective earth to operate correctly).

@betwixt: In my country is normal thing to have 3 phases in apartments/individual houses, most electric stoves are designed with possibility to be connected on two/three phases. It's good for load balancing :)

20191002_093918.jpg

Circuit breakers are not for protection of the equipment that is connected to them, but for protection of wiring to the equipment!
Equipment is protected with it's own fuse(s).

I don't know the Codes in Saudi Arabia, but I do not like that panel.
 
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    FvM

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Here the standard for 32A breakers is they feed a ring (so two paths to each socket) of 2.5mm copper. Looking at the bottom photo in post #6, in addition to the existing wires there would be a second pair of wires from the left outlet back to the fuse box giving effectively 5mm2 of copper to carry current. There would also be an earth wire looped in the same way.

Brian.
 

Brian,
I've not seen ANY PE wire in pictures in post #6. Just two sockets wired in parallel :)

Even the cross section of wires comming out of 32A breakers is inadequate.

For lazy people:
Screenshot_20191002-220402_ElectroDroid.jpg Screenshot_20191002-220316_ElectroDroid.jpg Screenshot_20191002-220338_ElectroDroid.jpg Screenshot_20191002-220255_ElectroDroid.jpg

Q: Do you have a ring feed in your home/apartment? What is the purpose of middle contact (longer one) on UK type mains plug? :)
 
OK guys here's the story I've encountered last night.

I asked an electrician to come and check the apartment. He told me that the entire room is powered with only 2 wires of 6mm from the main panel !!

Then these two wires enters the room and then everything is paralleled out; switches, lamps .. I think even the A/C, but maybe the A/C has a separate cables.

The apartment doesn't have distribution boxes in each room ... pretty much nothing much I can do as an addition or modification, the guy that did the wiring system, has done it in a tight system .. I can't pull a wire from the main panel.

We checked the main panel, it's 3-ph, start connection with neutral, the voltage between each phase is 391V, and from the any phase to neutral is 220V !! pretty amazing right :) it's like the new standard in Saudi Arabia, mostly in the moderate cities, I don't know about the villages, maybe they work on the old system.

This is what I think is the system we have here:
star-connected-winding-with-neutral-grounded.jpg



But I have an idea ! But this idea has been done by one of my friends, he had the same issue in his house and he just connected the third part of the socket which is meant for ground to neutral again and problem is solved !

the_trick.png

How about this ?? Of course it worked with my friend, he now doesn't have any issues regarding leaking current and getting those small shocks.
 

Do not connect third (ground) terminal with neutral. Lethal voltages could be present on chassis of metallic objects like washing machine, cooker, water heater, and you could be electrocuted, and even dead.
Neutral can be on higher potential than Protective Earth. Take care of yourself and your loved ones.
 

Do not connect third (ground) terminal with neutral. Lethal voltages could be present on chassis of metallic objects like washing machine, cooker, water heater, and you could be electrocuted, and even dead.
Neutral can be on higher potential than Protective Earth. Take care of yourself and your loved ones.

But my friend did it and it's working with him quite well !

Because as I explained in #18, we have 3-ph and neutral as a ground for the star connection. So the neutral works as a ground and neutral at the same time.
 

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