Quick And Dirty Grounding/Earthing Installation

[tim73]

What to do if you live in a high-rise condo or house and there is no access to proper grounding (aka thick copper rod in the ground, put 2 meters deep).

WARNING: You should know what you are doing before trying these instructions. 220V is not something you should be playing without being really careful. I will not accept any liability or responsibility if you get electrocuted/hurt/killed when doing these instructions. Do not try this while being intoxicated or otherwise impaired.

1. Buy from a supermarket (Tesco Lotus) an adaptor with three spikes. The earth connector is the bottom tiny connector in the photo. The one with hole in the middle of it. Buy also some kind of thin metal rod (30-40 cm long) and a couple of screws.

2. Buy cable thick enough. I used speaker cable, 20 meters. 10 baht per meter. (adaptor.jpg)

3. Buy big flower pot, bigger the better and put a lot of dirt and flower into it. (Maybe your wife can take care of this (flowerpot2.jpg). It should be at least 30 cm deep and 40 cm wide. Not any tiny flower pot will do, it has to be quite big. Put it outside of your room to the balcony if possible and NOT in any case to the shower/toilet room.

4. Strip the wire insulation off from one end of the cable and connect it to earth connector in the adaptor. Make sure the connection is solid. Then insulate it properly with duct tape. DO NOT YET CONNECT IT INTO WALL SOCKET. See wall.jpg how it should look.

5. The other end of the cable goes to flower pot. Strip wire insulation off again and connect the wire first to the metal rod (use screws). Then push it all the way into flower pot dirt. Not to the flower nor flower pot itself but too the DIRT and put is as deep as it goes. Yes, no faking, this is very important part. (flower_pot_grounding.jpg). Make sure the dirt is moist (that is why there is a flower :-).

I have also Leonics TPS-series surge protector (costs about 1800 bahts) and it has a fault wiring (=ground wiring) red led light. It should be OFF and in the photo (surge_protector.jpg) it is actually (although hard to see that) OFF and protected light is ON. The surge protector has six connectors so you can use grounding for more devices than just one. Some extension cords also have grounding connected but you never know here in Thailand, whether it is connected or not. Surge protectors always have ground connector.

6. Connect the adaptor to the wall and then connect that three spike connector from your computer or from surge protector into it. (wall.jpg).

This is not actually "proper" grounding but better than nothing. It is not like you can just drop 50 meters of cable down to ground level and dig a hole for a rod For computer/monitors this will do but for electric ovens or similar high powered devices you must call electrician.

Be careful.

[rakman]

The whole point of an "earth" is to drain the errant electricty to "ground", not to put it in some "dirt". Potentially, you're making a big capacitor with no where to go. You also might be creating an intermittent link to the building rebar in the concrete via a wet path.

Not sure this is a good method.

[givenall]

The whole point of an "earth" is to drain the errant electricty to "ground", not to put it in some "dirt". Potentially, you're making a big capacitor with no where to go. You also might be creating an intermittent link to the building rebar in the concrete via a wet path.

Not sure this is a good method.

The best ground is to connection to the rebar they use in the concrete especially the rebar in the main columns. That would give you the best possible ground in a high rise if you don’t already have grounded outlets, since you don’t have direct access to the ground [/b]

[tim73]

The whole point of an "earth" is to drain the errant electricty to "ground", not to put it in some "dirt". Potentially, you're making a big capacitor with no where to go. You also might be creating an intermittent link to the building rebar in the concrete via a wet path.

Not sure this is a good method.

There is no direct access to (1-2 meter deep) ground in many town houses or condos. There is no garden, it is all ceramics or asphalt. Water pipes are nowadays made of plastic and thus, no proper ground connection. So that is why big flower pot could be the only choice.

[tim73]

Forgot to add. You need also few cement blocks underneath the flower pot. Cement is used in dry conditions like in deserts to create so called Ufer ground.

[necronx99]

Hmm, the Electricians will be waking up and logging on soon.

I don't think they are going to be happy.

[handydog]

too dangerous. You make a BIG assumption the polarity of the phase and neutral are around the correct way.

Are you selling tickets to watch you do the "240 volt jig" ?

[T_Dog]

Flower pots and 240 volt ad hoc wiring is a very dangerous mix. I hope folks don't follow this advice but rather get a knowledgeable electrician to sort out high rise earthing. Often water systems are steel and offer a suitable grounding option.

[Crossy]

I'll let others make the comments I feel like making right now.

But I do have one question for our OP - Since you appear to have 3 pin outlets, what makes you think you need to arrange an additional earth?

[tim73]

I'll let others make the comments I feel like making right now.

But I do have one question for our OP - Since you appear to have 3 pin outlets, what makes you think you need to arrange an additional earth?

It is not connected to anything like in quite a lot of houses/condos in Thailand. Of course one should contact a good electrician if possible but it seems sometimes even they are in Thailand not very familiar with grounding issues.

So is it better to have an ad hoc ground wire to a flower pot with cement blocks underneath or be without it? It seems to be working for me and even surge protector seems to be ok with it (no fault wiring light).

[David006]

I'll let others make the comments I feel like making right now.

But I do have one question for our OP - Since you appear to have 3 pin outlets, what makes you think you need to arrange an additional earth?

This has got to be troll post just to get the sparkies to bite............if not very scary...

.....maybe plant some water cress in the pot ...should lower the impedance....

[xylophone]

This has to be a joke or the OP's lift doesn't go to the top floor??

[Crossy]

OK Chaps, I've done some tests using proper test gear.

We are on the 10th floor of the condo, so a similar situation to our OP.

Here are the results, I will let you draw your own conclusions.

THE TEST GEAR.

A Robin KTS1630 installation tester. One of the available functions is the Earth Loop Impedance (Loop on the function selector), this is a simple test of the efficiency of the available ground connection. The tester also has a set of lights that function in the same way as those on your surge arresting extension, these are the P-E and P-N lamps in the centre of the device. There is also a lamp marked 'Do Not Proceed', more of this later.

THE EARTH SPIKE

Part of the tester accessory kit, it's actually intended for measuring ground resistance (checking ground rods).

THE PLANTS

These are well established in their pots.

THE RESULTS

With the earth in the plant pot, the L-E and L-N lights illuminated, indicating that there was at least some sort of earth. However the 'Do Not Proceed' lamp also lit, this means that the tester has sensed more than 50V between the N and E terminals and will not perform the loop test. Not a very good earth methinks.

I noticed that the 'Do Not Proceed' lamp went out when I got hold of the earth spike whilst bare footed. Evidently I was a better ground than the plant (I had no intention of pushing the 'test' button whilst holding the spike). A further test with the plant pot base removed finally made 'Do Not Proceed' go out so I could perform a test.

Result - Over range, i.e. > 2k Ohms (the highest range available on Loop Test).

I thoroughly watered our plant and re-tested.

Result - 1790 Ohms. Not a good ground, but it would trip an RCD.

I also noticed that the 'Do Not Proceed' light was out with the spike lying on the damp concrete balcony, so a test was run in this mode too.

Result - Over range

THE ALUMINIUM BOWL

I borrowed this bowl from the Wife. With it sitting on wet concrete the tester deigned to perform a test.

Result - 1670 Ohms. Not a good ground, but it would trip an RCD.

THE BALCONY RAILING.

I scraped some paint off the railing and tested to that.

Result - 1.6 Ohms

FINALLY, THE REAL EARTH

Tested to the ground bar in our consumer unit. Supply is currently TT as we are on a temporary connection since the flooding wiped out the building transformer, however the main earth mat is still connected and in use.

Result - 1.4 Ohms. Actually very good for TT, I suspect the temporary transformer ground spike is very close to the main earth mat, it could even be making contact with it so we could actually have TN-S.

[tim73]

By western standards this is potentially dangerous. But if they are selling these adapters in supermarkets it seems to indicate many Thais are actually using these adaptors to make ad hoc groundings (in welding shops etc). Because they cannot afford to tear down the carpets and install a new line all over the place. Most Thai houses do not have grounding installed even if the wall sockets have one for the ground. Most expats live in quite luxurious houses/condos with proper groundings so it is none of their concern.

That is why I said be really careful and in any case you should call an electrician first if possible. Anyway, it seems to work in my house. Probably it is that "not a good ground", 1600 - 1700 ohms like Crossy measured but the fault wiring light in the surge protector stays off.

[Crossy]

OK, it's like this.

Your flowerpot ground will almost certainly prevent (or at least reduce) the tingle that you sometimes feel from your PC casework (caused by the mains inlet filter).

It MAY, cause your RCD to operate in the event of a L-E fault.

If you have no RCD then it will provide ZERO, NO, NADA, SOD ALL protection from electric shock and death.

Your surge protection will work no better than it would with no ground at all.

I expect that if you hold the spike in your hand in bare feet the fault light will go off too.

A flat metal plate under your plant pot possibly resting on a bit of damp carpet will provide a more reliable ground.

I am CERTAIN that you can find a better ground in your apartment, do you have a metal balcony railing?

[tim73]

I am CERTAIN that you can find a better ground in your apartment, do you have a metal balcony railing?

I tried metal gates, metal water tank and many other places and there is no access to ground, all paved. Not even a single tiny hole Unfortunately also, the water tank has rubber installation in its feet. No luck with the fault light except when I put 30 cm long metal thin rod into big flower pot with concrete blocks underneath. Concrete is used in the Ufer grounding systems so probably resembling that somewhat.

"In 1942, Herbert G. Ufer was a consultant working for the U.S. Army. Ufer was given the task of finding a lower cost and more practical alternative to traditional copper rod grounds for these dry locations. Ufer discovered that concrete had better conductivity than most types of soil. Ufer then developed a grounding scheme based around encasing the grounding conductors in concrete. This method proved to be very effective, and was implemented throughout the Arizona test site." - wiki.

[Crossy]

Yes, I know what an Ufer ground is, it's sometimes called a concrete encased electrode. It relies upon the encased electrode being buried in the ground.

Do you have an RCD? If you do not you would be well advised to get one installed ASAP.

[tim73]

Do you have an RCD? If you do not you would be well advised to get one installed ASAP.

Yes, there is RCD. So the fault wiring is measuring what exactly if it is not adequate to ensure RCD tripping? Isn't that supposed to mean, the installation is ok, there is proper grounding for surge protector?

Edited March 24, 2012 by tim73

[Crossy]

Yes, there is RCD. So the fault wiring is measuring what exactly if it is not adequate to ensure RCD tripping? Isn't that supposed to mean, the installation is ok, there is proper grounding for surge protector?

Good that you have an RCD.

The problem is that the indicator light isn't 'measuring' anything, it is merely indicating that the outlet is wired correctly and that there is a path to ground. The light triggers at a few milliamps and gives no real indication as to the quality of the ground itself.

As you saw from my testing, the similar functionality of a rather expensive piece of test gear indicates the presence of a ground when I have the rod in my hand, not a particularly good ground.

[tim73]

Good that you have an RCD.

The problem is that the indicator light isn't 'measuring' anything, it is merely indicating that the outlet is wired correctly and that there is a path to ground. The light triggers at a few milliamps and gives no real indication as to the quality of the ground itself.

Is it possible to check the quality of ground by simple multimeter or does one need that earth loop impedance tester? I believe the neutral and ground line should show less than a volt or two at least. Maybe the fault wiring circuit is measuring that voltage difference because the led does not switch off for all connections in the ground line. So it has some kind of threshold.

[Crossy]

You can do a cheap-and-cheerful ground test using a 15W light bulb (not a compact fluorescent) between L and E. With no RCD it should light, measuring the voltage across it will give you an idea how good the ground is, the higher the better. If you have an RCD it should trip.

The LED will have a threshold of 1.5 - 2.5 V dependant upon its colour.

The 'old' type outlet testers used neon lamps rather than LEDs, these don't strike until 50-60V and so needed a much better ground before they indicated 'good', newer is not always better. There is a reason I still have my antique outlet tester.

[tim73]

So the question remains, there is no good ground in years old condo since whatever and this balcony railing thing grounding sounds like you are going to electrocute anybody touching the rail if the malfunction happens! Especially if many of the other condo citizens are doing the same and the condo management do not give a shit for your requests of another line.

So what is your opinion, in that case, no good ground available, electricians or engineers? Is the flower pot with cement blocks the only choice? Or what would you do to create a ground?

Edited March 24, 2012 by tim73

[Satcommlee]

Some of the "advice" on here is going to get someone killed!

Really loved the flowerpot OP hilarious, but seriously some guy might have thought his dicky shower that gives him a few tingles would have been fixed by this joke!!

Consult an electrician for proper advice (preferably not Thai)... Over long distances cables have to be much thicker also, as for connecting to the steel re-enforcement (another stupid suggestion) I'd rather earth to a Sophon TV cable.

[Crossy]

Satcommlee, I have no issue when someone questions my advice, it happens a lot in my business.

However I get a little humpy when someone suggests that my advice is 'stupid' without justifying their comment. I would like you to explain exactly why using the building steel as a ground in the absence of a properly implemented electrical earth is a bad idea.

You may wish to Google 'Ufer ground' as mentioned by our OP before answering.

[necronx99]

Satcommlee, I have no issue when someone questions my advice, it happens a lot in my business.

However I get a little humpy when someone suggests that my advice is 'stupid' without justifying their comment. I would like you to explain exactly why using the building steel as a ground in the absence of a properly implemented electrical earth is a bad idea.

You may wish to Google 'Ufer ground' as mentioned by our OP before answering.

Isn't earthing to the slab reo standard in dry areas?

[Crossy]

Isn't earthing to the slab reo standard in dry areas?

Indeed

[Tywais]

I would like you to explain exactly why using the building steel as a ground in the absence of a properly implemented electrical earth is a bad idea.

Me too. If you look up water retention-concrete you will find it takes decades for it to dry out. With rebarb embedded it makes for a pretty low resistance path. I set up a friend of mine who lived in a Condo with a 'drain' path as he and his girl friend kept complaining about the standard 'computer tingle'. A wire running from the PC to a sanded spot on the railing stopped it. Yes, not an ideal solution. Quite safe in this particular situation (PC only & peripherals) due to the mechanism of where the tingle comes from and that is the front end EMI filters on the power supply which acts as an AC voltage divider to the PC chassis (ground). I wouldn't recommend it for items such as washing machines, frigs, microwave unless having an RCD/GFI.

[wpcoe]

What about running an earth wire up to the steel roof beams? I'm assuming that the metal roof structure is tied into rebar in the concrete support columns and would lead to the ground, no?

I may be moving back to my Jomtien condo which is on the top floor and I'd have easy access to run a ground wire up there. If a fault does occur could anybody touching a roof beam (maintenance guys, for example) be electrocuted?

[Crossy]

The roof beams would be a good option.

You must do a simple test to ensure that they really are grounded (unlikely that they are not). A 15W lamp between live and a connection to the item you want to use as ground is a simple test, it will light or your RCD will trip if the ground is adequate. Take great care if you perform this test, connect to your ground first, test briefly and keep clear of any metalwork.

An RCD is really an absolute requirement on any installation here. So if you don't have one get one installed as soon as possible, preferably before you start experimenting with alternative grounds.

With an RCD there is negligible hazard to someone in contact with the building metalwork when a fault occurs even if the connection to ground isn't perfect.

[dhrobertson]

Dangerous nonsense here.

I urge extreme caution.

1) Have ground performace at socket outlets tested. This only takes a few seconds with the correct gear. If unsatisfactory then the condominium ground system should be rectified. If necessary call the PEA/MEA.

2) Fit RCBO to protect against shock. These devices monitor neutral and phase currents. These should be the same. If they differ, then some current is being lost, possibly through you. In that case the RCBO disconnects the supply very quickly.

3) Surge suppression will just not work in the absence of a good ground connection.

Leave the plant pots to the plants