Jump to content

Electrical problem, socket not grounded/earthed, house not grounded/earthed, no electric wire to put on a nail behind the washing machine ?


Recommended Posts

Posted
1 minute ago, RocketDog said:

Are you sure the metal roof support is a good ground? Kinda counterintuitive since ground is, well.... Ground. Many roofs are supported by concrete posts with no obvious path to ground. No easy way to check this either. As direct a path to ground as possible is best.

The recommended is a ground rod.  The roof (or other structural steel) makes a good substitute (see "Ufer ground") when a ground rod is not feasible.  The roof steel is almost certainly welded to the rebar in the support columns and which continues to the footings making a good connection to "earth".

  • Like 1
  • Thanks 1
Posted
7 hours ago, bankruatsteve said:

The recommended is a ground rod.  The roof (or other structural steel) makes a good substitute (see "Ufer ground") when a ground rod is not feasible.  The roof steel is almost certainly welded to the rebar in the support columns and which continues to the footings making a good connection to "earth

OK. Good to know.

Assuming one is going to run a ground bus from the metal roof and distribute it to more than one other point, it would seem that creating a true ground rod outside the house for such a bus is equal effort and leaves no doubt in the the

matter.

 

 

 

 

  • Like 1
Posted

The first thing to do is to by a coppar pin. They are about 1 - 1,5 meter and you can find it in almost every electric shop. The copparpin are to be hammered down in the ground, under or close to your house. On the top of the pin there is a place to fasten an isolatede wire do that and draw that wire to your switchboard. Turn of the switchboard and connect the cable to the earth rail on your switchboard. Then you have to switch all the wallsockets that you want earthed to sockets with earth (if you have an electrical heater for your shower, do not forget that). Now comes the "dirty" work. And this is because your house probably only have two wires to each walletsocket. If you not want to change all the wires there is a simple but "dirty" solution. In at least my native country you are not allowed to do this, but here in Thailand you have not much of a choice. Ground and Zero is the same but in western country you should be able to disconnect them from each other for to get the right testing result if anything is wrong. So your next step is to override this by, in the grounded wall socket connect ground to zero (zero is usially the blue one). If you not think that you could do it yourself, hire an electrican to do it. I did that of laziness, but be shure to follow close what he is doing, most of them are not very well educated.  

  • Like 1
  • Sad 1
Posted
2 minutes ago, RocketDog said:

OK. Good to know.

Assuming one is going to run a ground bus from the metal roof and distribute it to more than one other point, it would seem that creating a true ground rod outside the house for such a bus is equal effort and leaves no doubt in the the

matter.

The "proper" method is to obtain ground from a ground rod to the CU.  The CU then distributes the ground from there.  The structure steel can be a good alternative when a ground rod is not feasible and/or impractical to implement.

Posted
5 minutes ago, Parsve said:

The first thing to do is to by a coppar pin. They are about 1 - 1,5 meter and you can find it in almost every electric shop. The copparpin are to be hammered down in the ground, under or close to your house. On the top of the pin there is a place to fasten an isolatede wire do that and draw that wire to your switchboard. Turn of the switchboard and connect the cable to the earth rail on your switchboard. Then you have to switch all the wallsockets that you want earthed to sockets with earth (if you have an electrical heater for your shower, do not forget that). Now comes the "dirty" work. And this is because your house probably only have two wires to each walletsocket. If you not want to change all the wires there is a simple but "dirty" solution. In at least my native country you are not allowed to do this, but here in Thailand you have not much of a choice. Ground and Zero is the same but in western country you should be able to disconnect them from each other for to get the right testing result if anything is wrong. So your next step is to override this by, in the grounded wall socket connect ground to zero (zero is usially the blue one). If you not think that you could do it yourself, hire an electrican to do it. I did that of laziness, but be shure to follow close what he is doing, most of them are not very well educated.  

Using neutral as ground is not allowed anywhere.  That is bad advice.

  • Like 2
Posted (edited)
16 minutes ago, expatfromwyoming said:

you jest- surely?????

As I said you just hammer it down, at least 50 to 80 centimeters so you are sure that it is wet ground around the rod. And do not listen to those who say that you should connect it to the structure steel they do not know what they are talking about.

Edited by Parsve
  • Like 1
Posted
4 minutes ago, bankruatsteve said:

The "proper" method is to obtain ground from a ground rod to the CU.  The CU then distributes the ground from there.  The structure steel can be a good alternative when a ground rod is not feasible and/or impractical to implement.

Yes, agreed. That is what I referred to as the ground 'bus'.

And also agreed to the roof as an alternative, but unless one can verify that is indeed earthed, it's just wishful thinking. That was my original point and it still stands.

 

In the end, a ground rod is a ground rod. Rebar inside concrete posts is just that since nobody ever makes an effort to ensure that the rebar is in proper contact with earth.

 

It's also true that few existing houses used 3 wire cable for power distribution in the house, so just bringing a good earth to the breaker box doesn't solve anything unless the load wiring carries the earth as well. Of course that's the proper way to do it if one is prepared to rewire the entire house.

 

For a single ground outlet, if anywhere near an outside wall, a simple hole in the wall with a proper ground rod outside still seems feasible.

 

At the end of the day, you pays your money and you takes your chances. Up to you.

Posted
7 minutes ago, Parsve said:

As I said you just hammer it down, at least 50 to 80 centimetrs so you are sure that it is wet ground around the rod. And do not listen to those who say that you should connect it to the structure steel they do not know what they are talking about.

I avoided being that blunt in my post and applied my reasoning.

Ground is ground and anything else is not.

 

It's also not good advice to attach a lightning rod to your roof steel hoping that will direct the jillion Amp lightning strike to ground.

 

Thank you.

Posted
On 7/11/2019 at 10:30 AM, myjawe said:

 

Before You Do Anything Else

The first thing to do to get safe(r) is to install an ELCB (RCCB, RCD, GFI, Safe-T-Cut)

 

 

ELCB need the earth cable to work so don't buy that. Better to buy a 20A or 30A earth leakage breaker like this one and install it after the main breaker so it protects the whole house. 

Screenshot_20190712-165514_Shopee.jpg

Posted (edited)
23 minutes ago, RocketDog said:

I avoided being that blunt in my post and applied my reasoning.

Ground is ground and anything else is not.

 

It's also not good advice to attach a lightning rod to your roof steel hoping that will direct the jillion Amp lightning strike to ground.

 

Thank you.

I have never talked about putting the rod on the roof, could you please explain as you cite my comment. And ground and zero is for sure the same. If you look in your switchboard you will see they are connected.

Edited by Parsve
wrong spelling
Posted (edited)

*Difference between ELCB and RCCB(RCD)

  • ELCB is the old name and often refers to voltage operated devices that are no longer available and it is advised you replace them if you find one.
  • RCCB or RCD is the new name that specifies current operated (hence the new name to distinguish from voltage operated).
  • The new RCCB is best because it will detect any earth fault. The voltage type only detects earth faults that flow back through the main earth wire so this is why they stopped being used.
  • The easy way to tell an old voltage operated trip is to look for the main earth wire connected through it.
  • RCCB will only have the line and neutral connections.
  • ELCB is working based on Earth leakage current. But RCCB is not having sensing or connectivity of Earth, because fundamentally Phase current is equal to the neutral current in single phase. That’s why RCCB can trip when the both currents are different and it withstand up to both the currents are same. If both the neutral and phase currents are different that means current is flowing through the Earth. Usually the current flowing to Earth that is needed to cut of the Electric Power in the breaker is less than 30 mA and happens within 0,1 second.
  • Finally both are working for same, but the thing is connectivity is difference.
  • RCD does not necessarily require an earth connection itself (it monitors only the live and neutral).In addition it detects current flows to earth even in equipment without an earth of its own.
  • This means that an RCD will continue to give shock protection in equipment that has a faulty earth. It is these properties that have made the RCD more popular than its rivals. For example, earth-leakage circuit breakers (ELCBs) were widely used about ten years ago. These devices measured the voltage on the earth conductor; if this voltage was not zero this indicated a current leakage to earth. The problem is that ELCBs need a good earth connection, as does the equipment it protects. As a result, the use of ELCBs is no longer recommended.
  • RCBO (O for overload) also have an ordinary fuse included in the breaker. It will protect everything inside your house including all the devices that are not earthed as well. Residual Current Circuit Breaker with Over Current Protection RCBOs are commonly used in applications where there is the need to combine protection against overcurrents (overload and short-circuit) and protection against earth leakage currents. RCBOs help in sensing this kind of faults and trip the circuit ensuring complete protection of the people and connected equipment.
Edited by Trollmann
Posted (edited)

Am I allowed to give a small correction to what is just told. What we are talking about is a one phase connected  electrical item. That means that it has two wires conected to it or preffable three. Phase, zero and in some cases ground. Of those two or three there is one who is  the one who is the carrier of the voltage, the phase, but it need also the zero to work (still zero and earth is connected). The elecrtical item is uselly not attacted to the ground if it is not done internal as it is standing on rubber or plastic wheels while you come there barefoot and then you are connected to the earth and the current leads within you. Thats why you have to make shure that the cover of the machine is grounded, especially in wet places.

Edited by Parsve
Wrong in sentace
Posted
42 minutes ago, Parsve said:

Am I allowed to give a small correction to what is just told. What we are talking about is a one phase connected  electrical item. That means that it has two wires conected to it or preffable three. Phase, zero and in some cases ground. 

You are allowed to correct yourself. You are not allowed to claim others don't know what they are talking about. FWI: In Thailand, what is called "MEN" is the only distribution system that bonds N to E at the CU. The 2-3 others do not and are currently the majority. Tj

Posted (edited)
2 hours ago, bankruatsteve said:

You are allowed to correct yourself. You are not allowed to claim others don't know what they are talking about. FWI: In Thailand, what is called "MEN" is the only distribution system that bonds N to E at the CU. The 2-3 others do not and are currently the majority. Tj

Sorry, I was not corrected my self and of course I have the right to tell if others are wrong and for the rest you are talkning about, I have no clue what you mean. Could very well be beauce English is not my native language.

Edited by Parsve
Misspelling
Posted (edited)
6 hours ago, RocketDog said:

In the end, a ground rod is a ground rod. Rebar inside concrete posts is just that since nobody ever makes an effort to ensure that the rebar is in proper contact with earth

It would seem that you do not understand what a Ufer earth is.

 

The rebar is not in contact with the Earth, the concrete with enough rebar inside a sufficient amount of concrete is a good earth. Concrete is not a good electrical insulator.

 

If your all your foundation rebar is connected and your foundations are big enough for a Ufer earth and the soil structure/moisture conditions are correct  a ground rod is just icing on the cake.

Edited by sometimewoodworker
Posted
6 hours ago, Parsve said:

And do not listen to those who say that you should connect it to the structure steel they do not know what they are talking about.

Structural steel can be use an earth please check the work of Herbert G. Ufer and the US electrical code that in some states require a Ufer ground.

  • Like 1
Posted
20 hours ago, Parsve said:

I have never talked about putting the rod on the roof, could you please explain as you cite my comment. And ground and zero is for sure the same. If you look in your switchboard you will see they are connected.

Attention all readers of my post:

 

PARSVE never mentioned lightning rods in his post. That was entirely my comment.

Posted
14 hours ago, sometimewoodworker said:

Structural steel can be use an earth please check the work of Herbert G. Ufer and the US electrical code that in some states require a Ufer ground.

Maybe so, but I've never personally lived in or seen a house in the USA that used structural steel. I guess it's a question of the income class I'm in! Most homes in the USA are 'stick built', meaning wood.

 

I'll investigate Ufer grounds next time I build a steel house though.

 

Posted
14 hours ago, sometimewoodworker said:

It would seem that you do not understand what a Ufer earth is.

 

The rebar is not in contact with the Earth, the concrete with enough rebar inside a sufficient amount of concrete is a good earth. Concrete is not a good electrical insulator.

 

If your all your foundation rebar is connected and your foundations are big enough for a Ufer earth and the soil structure/moisture conditions are correct  a ground rod is just icing on the cake.

I can buy a copper rod and a piece of wire at any hardware store. The path to ground is as long as the wire. No concrete or rebar needed.

 

To imply that concrete is as conductive as soil is simply disengenous. I'm not saying Ufer systems don't serve, but I am saying concrete and dirt are different things, and earth is highly ionic and much more conductive than concrete. Copper is more conductive than iron. These are indisputable facts.

 

You can have the last word. I'm bored with the conversation.

Posted

Just to throw my input into the mix. Our home is concrete and steel, we also have the requisite 2.4m copper-clad-steel rod (there's no way you would drive a pure copper rod this long, copper is just far too soft [and expensive]).

 

Whilst the re-bar was not designed to be electrically continuous there is so much of it and there are many (many) wired crossings. The actual integrity was demonstrated by the chaps welding the roof steel, the welder return was attached to a bit of rebar at ground level, only one wire needed up to the torch.

 

Using an earth resistance tester (yes, a proper one) the roof steel actually provides a rather better ground than the driven rod ????

 

Both linked (the rod keeps the PEA inspector happy) and we have a more than solid earth.

 

  • Like 1
  • Thanks 1
Posted

And some more for the mix . .

 

Back in WW2 the Yanks were having problems with lighting blowing up bomb storage units and needed a way to dump natures huge electrical pulses before they got into the TNT.

 

Herbert Ufer observed that the high PH of concrete would provide a ready supply of ions and in turn provide a better electrical ground than almost any type of soil. Ufer also found that the soil around the concrete became doped and the rise in pH caused the overall impedance of the soil itself to be reduced. The concrete enclosures also increases the surface area of the connection between the grounding conductor and the surrounding soil further helping to reduce overall impedance of the connection.

Posted
1 hour ago, RocketDog said:

To imply that concrete is as conductive as soil is simply disengenous. I'm not saying Ufer systems don't serve, but I am saying concrete and dirt are different things, and earth is highly ionic and much more conductive than concrete. Copper is more conductive than iron. These are indisputable facts.

I don't imply that a US army consultant found that 

 

Quote

In 1942, Herbert G. Ufer a consultant working for the U.S. Army. He discovered that concrete had better conductivity than most types of dry soil.

 

  • Like 1
Posted
1 hour ago, RocketDog said:

Maybe so, but I've never personally lived in or seen a house in the USA that used structural steel. I guess it's a question of the income class I'm in! Most homes in the USA are 'stick built', meaning wood.

So none of the houses you have seen have reinforced concrete  foundations? You must have had blinkers on whenever you have looked at a building site. 

 

The steel in the foundations is the only steel that matters, unless you are talking about lightning protection, other steel just makes a convenient point to attach to. 

  • Like 1
Posted
1 hour ago, sometimewoodworker said:

So none of the houses you have seen have reinforced concrete  foundations? You must have had blinkers on whenever you have looked at a building site. 

 

The steel in the foundations is the only steel that matters, unless you are talking about lightning protection, other steel just makes a convenient point to attach to. 

So you've never seen houses in the south or locations with heavy clay or bentonite soil that sit on pier foundations. But wait, often the foundation support blocks are concrete, so I can bore a hole in them for a ground instead of just driving a rod in the ground like such houses normally do. It's just so intuitive. I love it. This could revolutionize the building industry. But wait, my house in America has a slab foundation but also features a metal ground rod immediately below the breaker box. Poor ignorant savages.

 

OK, I'll just bore holes in the concrete slab floor and find some rebar.

Or maybe just push some wire into the hole and patch over with more concrete.

 

So much easier than pounding a rod into the ground, and a great topic for party conversation.

 

Great idea. It just keeps getting better.

 

Next time I pour a house foundation I'll drop a wire in it.

Posted (edited)
3 hours ago, RocketDog said:

So you've never seen houses in the south or locations with heavy clay or bentonite soil that sit on pier foundations.

Something like this ?

IMG_0314.JPG.0a601cbef815bc592c7007ec9cfebbd2.JPG

This has a great enough area for an excellent Ufer earth.

 

3 hours ago, RocketDog said:

But wait, often the foundation support blocks are concrete, so I can bore a hole in them for a ground instead of just driving a rod in the ground like such houses normally do. It's just so intuitive.

Nobody has ever suggested that that will work. You have to connect to the rebar in the foundations for stick build and that needs to be done during construction.

Quote

A new exception was added to 250.50 in the 2005 NEC, which states that concrete-encased electrodes are not required for existing buildings or structures where the conductive steel reinforcing bars aren't accessible without disturbing the concrete.

 

3 hours ago, RocketDog said:

But wait, my house in America has a slab foundation but also features a metal ground rod immediately below the breaker box. Poor ignorant savages.

I agree completely with you and your characterising of your fellow countrymen. Who can't/don't read your own electrical codes.

 

3 hours ago, RocketDog said:

Next time I pour a house foundation I'll drop a wire in it.

Done correctly as @Fruit Trader has shown you it is code compliant and correct, further it isn't going to degrade as your earth spike will.

 

Just because you can't understand/can't be bothered to read the US electrical code and the abundance of information showing that concrete-encased electrodes (Ufer ground) works and is now required 

 

Quote

if a new building contains rebar in the footing or foundation, it must be used as a grounding electrode. This electrode would serve as the supplement water pipe electrode that is required by 250.53(D)(2).

 

Note: Ground rods will no longer be necessary for most new construction, since virtually all new construction uses concrete encased reinforcing bars or rods in the foundation. Since they exist, they must be bonded to and used as part of the grounding electrode system. 

This could mean that your information dates from the Jurassic ???? or at a minimum before 1975.

 

Quote

The steel reinforcing bar concrete-encased electrode was first introduced in the 1975 NEC.

 

Edited by sometimewoodworker
Posted

This is a diagram of a safe installation. The panel has a ground rod that grounds the earth bar and incoming neutral. All circuits have a separate ground wire that provides a low impedance path for fault currents, ensuring the breakers open and remove the voltage from the faulted appliance. Also, there is an earth leakage breaker before the main circuit breaker.

 

post-45135-0-23261900-1388647418.png

Posted

And now, as seems to happen with most threads concerning earthing I'm going to close this. 

 

Our OP has his answer.

 

:mfr_closed1:

  • Like 1
Guest
This topic is now closed to further replies.
  • Recently Browsing   0 members

    • No registered users viewing this page.



×
×
  • Create New...