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  1. #41
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    Re: Mains leaking currents causing problems in my house

    Quote Originally Posted by eagle1109 View Post
    How about this protection when doing a bootleg ?

    Attachment 156053
    The term bootleg, pretty much says what is wrong with this method of "fixing" the ground wiring issue in your apartment.
    boot·leg
    /ˈbo͞otˌleɡ/
    adjective: bootleg
    (especially of liquor, computer software, or recordings) made, distributed, or sold illegally.
    Basically it bypass and probably violates a bunch of Saudi building codes (at least that is definitely true in the US). Doing something that is inherently wrong isn't going to make this safer for you, in fact it will likely make it more dangerous for you if something should happen where you do need a true ground fault protection, of course you won't know about that situation because you will already be dead.

    I image that the building codes for your apartment were violated or somehow circumvented by the owner (builder) to cut costs. Like I previously mentioned, I would consider moving before fixing what should be the owner's responsibility.

    If you absolutely can't bear moving because the place is even more awesome than life itself, then I would do as has been suggested and wire in a ground to your apartment and connect it to a 2.5 m galvanized steel rod driven into the ground until only a few centimetres are showing. The main issue will be trying to route that ground wire throughout the apartment (preferably inside the walls where it belongs.

    Good luck and avoid dying. I suggest buying a plastic or wood stick to turn on and off your computer from now on.



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    Re: Mains leaking currents causing problems in my house

    You could go around cutting out all the Y caps ( RFI caps that go from phase & neutral to "earth" ) inside the appliances that have them - this should stop you getting a boot off your PC - or install a large isolating transformer near your switchboard which will effectively float the Ph & Neutral and not give you a shock when you touch a metal chassis ...



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    Re: Mains leaking currents causing problems in my house

    Removing Y capacitors can reduce ground leakage, but it doesn't change the fact, that a PC PSU isn't designed with reinforced insulation, thus ground faults can happen. Neither appliances like dish washers are. You can run a PC through safety transformer, but not a dish washer or electric cooker. Thus I repeat my previous suggestion to apply RCD in combination with local ground (TT earthing scheme) for critical devices.



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    Re: Mains leaking currents causing problems in my house

    A PC psu should be designed to at least 2.5kV ac phase to o/p's if not it is a very bad PC to own

    a dish washer could be run thru an isolation Tx - but an electric cooker would require ~ 5kVA, hopefully there are no Y caps in a cooker.

    A local earth connection only helps if one side of the mains is indeed earthed back at the mains TX - too much triplen current in the building neutral can give rise to local earth rise potential - ironically due to lots of PC's on the mains ....



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    Re: Mains leaking currents causing problems in my house

    Quote Originally Posted by betwixt View Post
    I think the "not grounded" indicator is to warn you the protection isn't going to work.
    Which indicator ? Do you mean the one in the drawing ? That drawing is did it myself to explain my idea about the problem.

    All 'surge protectors" and similar protection devices are filters and over-voltage traps that rely on a good earth being available. Without a 'ground zero' to send unwanted current to, they cannot possibly work and may make your situation considerably worse. Similarly, an RCD is unlikely to have much effect, they look for differences in the live current and neutral current. They should be the same because the current flows in a loop through the appliance (your PC) up one wire and down the other. They 'trip' if current leaks out somewhere and causes an imbalance but without an earth there is nowhere for the leaking current to flow to. The tiny current that gives the electric shocks is far less than 30mA!
    OK, so surge protectors and RCDs are different !

    But the idea I put in the later drawing with the blue box as the RCD is between the neutral and ground short, because I want to bootleg those two parts.

    I did a little experiment this evening with the new PSU I bought recently. I connected the PSU directly to the wall as in the picture and measured the current between the neutral and ground.

    Click image for larger version. 

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    Well, as thered probe in the neutral of the wall socket and the black is touching the exposed parts of the PSU, when I touches the exposed parts, there are tiny sparks of currents but the DMM at AC current measurement reads 0A !!

    So this way I know that there's no flowing of current if I bootlegged those 2 wires together. But why ? The voltage is 110V, why the current is 0A ? is it because of the capacitor connected between ground and neutral at filtering AC input ?

    This picture I took from the old PSU, I didn't want to open the new one because I don't want to void the warranty.

    Click image for larger version. 

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    Does the capacitor work as open circuit between the 3 terminals ?


    Question, is your room at or near ground level?
    My apartment is in the first floor, so I'm above the floor level.

    I'm wondering if it is possible to add your own ground through an earthing rod in the ground.
    I thought about doing a dig near the building and install the crude oil and salt to establish earthing environment. It would be a bit expensive for me, I'm trying to find any solution before I go to that solution.

    And another thing is that I think I'm too scared to bootlegging the neutral to ground because one of our friends did it and it's working fine with him, no problems ! I think I'm little paranoid about that, maybe our 3-ph + 1 neutral is ground from the distribution point !



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    Re: Mains leaking currents causing problems in my house

    Which indicator ? Do you mean the one in the drawing ?
    No, I meant the one in the Belkin device in post #38.

    I understand your confusion over this, there are factors most people wouldn't think twice about but then most people have a grounded socket. The underlying problem is that inside the PSU there is a filter, sometimes built inside the socket, sometimes on the main PCB. The filter is there because a PC PSU by the nature of it's operation, produces a considerable amount of interference and the cable would act as an antenna. I has the potential to wipe out nearby radio signals or interfere with TV or medical equipment. The way the filter works is it contains components that are more conductive at higher frequencies and they are wired between the live and earth and the neutral and earth pins of the PC power inlet. The case is also wired to the earth pin. As the mains AC is 50Hz or 60Hz, very low frequency, the components are only slightly conductive. At higher frequencies used for communication they are much more conductive so they can 'dump' more of the signals to earth while at mains frequency the 'dumping' is much less.

    Take a step back and see what happens when the earth connection is removed: both the live and the neutral have components connected to the earth pin, typically they are the same value so the earth pin adopts a voltage which is about half the mains AC. If you had a real earth connection and you measured the voltage from it to the PC chassis it would show about 230/2 = 115V.

    However, those filter components are only slightly conductive at mains frequency so they are incapable of producing much current. There is enough to give an electric shock but by connecting a current meter to it, you are basically pulling the chassis to the same voltage as the other meter probe and you see almost no current at all.

    There is no electrical way to get around this situation except to add a real 'planet Earth' connection. If you remove the AC filter in the PSU the problem may be reduced but at the expense of causing interference to neighbors. It also doesn't overcome the other purpose of having an earth connection, for safety in case the PSU breaks down. Adding an isolation transformer will help because it removes the direct connection to the AC wall supply and therefore the amount of current that can flow directly out of it through your body but all attached devices have to be on the same or another isolated supply. Because their 'grounds' are linked together through the connecting cables (USB etc) if any of them is NOT on an isolated supply, it make the isolation useless.

    I hope that makes sense to you, my apologies if I don't make it clear. Sometimes those of us who have been in industry for half a century take it for granted everybody else has the same amount of experience!

    Brian.
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    It's better to share your questions and answers on Edaboard so we can all benefit from each others experiences.


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  7. #47
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    Re: Mains leaking currents causing problems in my house

    Quote Originally Posted by betwixt View Post
    No, I meant the one in the Belkin device in post #38.
    Oh, OK; then I got your explanation about those Belkin power strips that they won't work for my problem. And thank for explaining how they work and that they contain over voltage protectors and not current leaking protectors.


    I understand your confusion over this, there are factors most people wouldn't think twice about but then most people have a grounded socket. The underlying problem is that inside the PSU there is a filter, sometimes built inside the socket, sometimes on the main PCB.

    The filter is there because a PC PSU by the nature of it's operation, produces a considerable amount of interference and the cable would act as an antenna. It has the potential to wipe out nearby radio signals or interfere with TV or medical equipment.
    wow I didn't know that .. so that coil is also a suppressor for those EMI signals like the one come with a gaming controller.



    Now I got that idea, so everywhere I have some kind of EMI, there has to be coils and capacitors to suppress those unwanted noises.

    Also, there are a lot of other protection and suppression circuits in a PC PSU system; like, surge current/over voltage protectors that come after the mains filter and consist of 1:1 isolating transformers and other high voltage capacitors. All these stuff come at the beginning to secure the after work of the device. That's one very important principle about electronic devices design.


    The way the filter works is it contains components that are more conductive at higher frequencies and they are wired between the live and earth and the neutral and earth pins of the PC power inlet.
    As the mains AC is 50Hz or 60Hz, very low frequency, the components are only slightly conductive. At higher frequencies used for communication they are much more conductive so they can 'dump' more of the signals to earth while at mains frequency the 'dumping' is much less.
    Oh yeah I found a video on YouTube that talks about Ferrite Beads: Filters, EMI Suppression, Parasitic oscillation suppression, so I learned that they use ferrite beads to suppress high frequencies.

    And I read that capacitors are also used for spikes EMI suppression and varistors for high voltages, how about my information ? are they near to correct ?

    So I think the combination for all filtering components at PSU input are essential, ferrite beads, film capacitors, varistors, isolating transformers and also other possible filtering components.

    The case is also wired to the earth pin.
    That's an important key; that would let me at least operate my computer now without putting the motherboard and the other stuff under the 110V leaking voltage. Which is to put the PSU out of the case, now this why the 110V is only present on the case of the PSU :)


    Take a step back and see what happens when the earth connection is removed: both the live and the neutral have components connected to the earth pin, typically they are the same value so the earth pin adopts a voltage which is about half the mains AC. If you had a real earth connection and you measured the voltage from it to the PC chassis it would show about 230/2 = 115V.
    wow thank you so much for this explanation. It's like a voltage divider, but not entirely because the mains 220V isn't referenced to the ground after all or it's really grounded to the chassis ground and that's all.

    However, those filter components are only slightly conductive at mains frequency so they are incapable of producing much current. There is enough to give an electric shock but by connecting a current meter to it, you are basically pulling the chassis to the same voltage as the other meter probe and you see almost no current at all.
    Yeah ! Absolutely !! What does that mean ? So if I bootlegged the neutral to ground, I think there won't be a short current because I measured the current between the two terminals and it was almost 0 ampere except those small sparks when I touch the PSU chassis.

    But isn't it like shorting the area over the capacitor from ground to neutral. Like this:

    Click image for larger version. 

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    So won't that mean as I measured almost 0 ampere, if I bootlegged the mains neutral to chassis ground would work ?

    Note: I didn't try to measure current from L to chassis, I was so scared to do that because a very high current could flow and destroy the DMM 10A fuse, as it even too scary for me to even think about it ! If my calculations are true, so if mains voltage is 220V and the DMM is like 1 ohm, then 220A could flow through the DMM !!


    Why people tell me that if N become at potential, what could put voltage on N ? I know it's the way back of the L voltage but I measured almost no current from N to chassis ground.


    There is no electrical way to get around this situation except to add a real 'planet Earth' connection.
    I agree with you, but there could be a possibility that the main panel from our district transformer is grounded, won't that explain why I measured no current from N to ground.

    If you remove the AC filter in the PSU the problem may be reduced but at the expense of causing interference to neighbors. It also doesn't overcome the other purpose of having an earth connection, for safety in case the PSU breaks down. Adding an isolation transformer will help because it removes the direct connection to the AC wall supply and therefore the amount of current that can flow directly out of it through your body but all attached devices have to be on the same or another isolated supply. Because their 'grounds' are linked together through the connecting cables (USB etc) if any of them is NOT on an isolated supply, it make the isolation useless.
    So removing those two blue caps won't break the operation of the PSU but of course would disable the functionality of eliminating the stability and suppressing the no

    I hope that makes sense to you, my apologies if I don't make it clear. Sometimes those of us who have been in industry for half a century take it for granted everybody else has the same amount of experience!
    Brian.
    Actually I'm overwhelmed by your rich information and explanation of this situation, you helped me a lot in other issues I came across in other threads. It's really an honor for me to learn from you :)



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    Re: Mains leaking currents causing problems in my house

    I recorded this video this morning.




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    Re: Mains leaking currents causing problems in my house

    regarding your video; the meter is so high impedance that the small amount of capacitance in the cable is able to provide a signal to the meter which it sees as 98V - as there is no earth pin on the plug you are certainly not measuring to earth - but rather from live and then through the cable capacitance to neutral ...

    My firm advice is to move to another apartment with proper wiring ...


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    Re: Mains leaking currents causing problems in my house

    You can record as many videos as you like, and buy as many gadgets called "testers", but electrical installation in that apartment is UNSAFE!
    I guess that I wrote that you should not use DVM rather ordinary AVO meter with needle and NO electronics inside.

    You are just wasting your and ours time continuing this topic. You read all our opinions stating that the installation is UNSAFE and that somebody could be electrocuted.
    Make no mistake between my personality and my attitude.
    My personality is who I am.
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    Re: Mains leaking currents causing problems in my house

    Quote Originally Posted by Easy peasy View Post
    regarding your video; the meter is so high impedance that the small amount of capacitance in the cable is able to provide a signal to the meter which it sees as 98V - as there is no earth pin on the plug you are certainly not measuring to earth - but rather from live and then through the cable capacitance to neutral ...

    My firm advice is to move to another apartment with proper wiring ...
    OK, so it could be the capacitance. Also thank you for your advice and reply to my post.

    But moving to another apartment won't be as effective because pretty much most the buildings are done in this way and considering this is a new building that is less 4 years old.

    But I called the electricity company yesterday and they told me to come to planning office and talk to them about the grounding issue.

    It could be possible that they are grounding the neutral from the main transformer and if that's true then it would safe to bootleg the neutral to ground.

    Quote Originally Posted by ZASto View Post
    You can record as many videos as you like, and buy as many gadgets called "testers", but electrical installation in that apartment is UNSAFE!
    I guess that I wrote that you should not use DVM rather ordinary AVO meter with needle and NO electronics inside.

    You are just wasting your and ours time continuing this topic. You read all our opinions stating that the installation is UNSAFE and that somebody could be electrocuted.
    Thank you for taking time to write me a advice and information about my issue. I actually didn't think of buying an AVO.

    Also I'm really sorry that I'm wasting any body's time. But you are true that the electrical installation is not safe.



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    Re: Mains leaking currents causing problems in my house

    Click image for larger version. 

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    It turned out that the neutral is grounded :)

    I bootlegged the neutral to ground and it works fine now.



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    Re: Mains leaking currents causing problems in my house

    What is up with all that stuff in the bottom of this power closet?

    Is that the Rub al-Khali in there?

    Oh boy, it must be a major pain to clean up around there...<4 years and you've got dunes of the stuff sitting in there!


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    Re: Mains leaking currents causing problems in my house

    The N and Earth should be connected at your apartment disti board any way - this is MEN practice - it appears the wiring was done in a hurry and the neutral-earth link was never fitted ...


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    Re: Mains leaking currents causing problems in my house

    Quote Originally Posted by ads-ee View Post
    What is up with all that stuff in the bottom of this power closet?
    That's Saudi Arabia :)

    It was a dust wave went through our city couple weeks ago. But we don't have this so often, it's once in months.

    Is that the Rub al-Khali in there?
    Certainly it's


    Oh boy, it must be a major pain to clean up around there...<4 years and you've got dunes of the stuff sitting in there!
    Life clean itself :) lol I'm kidding but it's not a problem ..




    Quote Originally Posted by Easy peasy View Post
    The N and Earth should be connected at your apartment disti board any way - this is MEN practice - it appears the wiring was done in a hurry and the neutral-earth link was never fitted ...
    They didn't consider installing it in the first place, most building, I won't say ALL, but most don't install it. It's not necessary, now our electricity company in the big cities has put the rule to install earthing in any new house, otherwise they won't run current to your panel.

    I think this building didn't catch this rule. But the neutral is grounded in the district room, so bootlegging now is better than leaving those voltages floating on the appliances.



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    Re: Mains leaking currents causing problems in my house

    Just be sure never to use reversible plugs or you will find out the hard way what happens when you connect the PC case to live instead!

    I think the standard plug in Saudi is similar to the UK ones with an offset earth pin so it can't be fitted upside down but you can see the problem in countries where live an neutral can be swapped by rotating the plug 180 degrees.

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    Re: Mains leaking currents causing problems in my house

    Quote Originally Posted by betwixt View Post
    Just be sure never to use reversible plugs or you will find out the hard way what happens when you connect the PC case to live instead!
    ha ha :) yep I know what 220V feels like :) I touched 220V on a CRT TV motherboard couple times and the power was on.

    You are right ! I've done the bootleg after assuring that I'm connecting the neutral to ground.

    But I don't know if I did a mistake or not, I plugged the PC after connecting all the parts, forgot to connect the CPU cable. And switched the power on, the PC started to switch ON/OFF as long as the power on. I removed the GPU and connected the CPU. And things changed after that time.

    Now the PC won't boot and gives me error code A9 every time I try to boot it up. I read the manual is say "bios setup started".

    The TV is black screen and blinking cursor.

    Maybe the CPU or motherboard is gone.

    I think the standard plug in Saudi is similar to the UK ones with an offset earth pin so it can't be fitted upside down but you can see the problem in countries where live an neutral can be swapped by rotating the plug 180 degrees.

    Brian.
    Yep most of appliances and pretty much everything should work in both directions, now people started to put the g type plug in apartments and buildings.

    But with this new move, many people who build their own houses or apartments for rent don't install earth. But I think big commercial hotels, hypermarkets, malls, companies .. etc. may install earthing.

    I hope this bootleg won't cause any troubles to my stuff, because as this test today and the PC didn't start I think something went wrong !! I don't know, my friend who did this bootleg didn't have any issue. So I'm not sure what happened, I'm firing the PC now every time from the same modified plug ..



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    Re: Mains leaking currents causing problems in my house

    Just to point another arising problem !

    With bootlegging the ground pin to neutral wire, problem with appliances that have g type plug that have 3 prong is solved.

    But I guess there have been a compromised one. My coffee grinder has this type of plug.



    Now the appliances that have g type 3 prong have been got lower floating ground voltage, measuring the AC voltage between the cases to mains neutral.

    But the one with 2 prong has 202V floating on its case !! So I disconnected it from the power strip that is connected to the wall socket that has the bootleg.

    And connected it to a wall socket that doesn't have a bootleg wire, so the floating voltage is lowered to 145V as before.

    So is there a solution for this one ?



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    Re: Mains leaking currents causing problems in my house

    But the one with 2 prong has 202V floating on its case
    What devices are you talking about? Appliances with two pin connector are designed with safe insulation. If they involve metal cases or parts, the earth leakage current must be limited to safe values, no matter how the are connected. Indicated by the class II double square symbol, see https://en.wikipedia.org/wiki/Appliance_classes

    Measuring a voltage with a high impedance DMM gives no useful information about leakage. But depending on the device design, the voltage may change if you turn the plug by 180 degree.


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    Re: Mains leaking currents causing problems in my house

    Quote Originally Posted by FvM View Post
    What devices are you talking about? Appliances with two pin connector are designed with safe insulation. If they involve metal cases or parts, the earth leakage current must be limited to safe values, no matter how the are connected. Indicated by the class II double square symbol, see https://en.wikipedia.org/wiki/Appliance_classes
    My appliances with 3 prong are:
    1. Ariston 3 in 1 clothes washer



    2. Ariston dish washer


    3. Nuova Simonelli espresso machine


    My 2 prong appliance that gave 208V on the first plug position and 10V on the other position.
    Eureka coffee grinder




    Measuring a voltage with a high impedance DMM gives no useful information about leakage. But depending on the device design, the voltage may change if you turn the plug by 180 degree.
    wow .. you're totally right. I turned the plug 180 degrees and the voltage is 10V !! thank you so much ! but why that happened ? isn't any AC appliance suppose to work on any polarity ?



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