Grounding Rods

[Daffy D]

I just hammer them into the ground till there are about 3in showing and connect the wires and leave it at that.

Just been reading the instructions for installing a hot water shower and it says the top of the rod should be about 70cm below ground level.

Does it really matter? I would have thought with the wire connection above ground where you can keep an eye on it would be better.

For those interested I've got a one and half meter rod in the ground right near the toilet outlet thingy so that should give a good earth connection

[Crossy]

Hope you didn't put it through the pipe

Current wisdom is that the end of the rod should be below ground level but the connection should be protected from contact with the ground by a plastic tube (in the UK you can get specially moulded boxes). The connection should also be painted with acrylic paint to reduce corrosion.

What you have sounds reasonable protect the connection and you'll be good to go.

Don't forget to use an RCD as well for added protection, you can never be too safe.

[Lovedog100]

In the states a rod is required to be 2.4 meters long, driven down until just the connection shows just above the earth. Most states are requiring two rods be driven 2 meters apart. The connection being underground will cause corrosion. We don't paint them in the states, and I doubt that it would be needed here. England gets a lot more rain than Thailand.

[Daffy D]

Hammering the rod through an underground pipe is always a worry but I know where the pipes are at this place so no problem.

The hot shower comes with a built in ELCB (that's the same as RCD ) and in addition I wired all the shower room connections, light, fan, through an additional ELCB so should be double safe. And yes and the light switch is on the outside of the room.

Didn't like the idea of painting the grounding rod / wire connection, have this idea the paint will run down between the wire and the rod and insulate one from the other. What I've done is smothered the connection joint in Vaseline, well it's good for car battery terminals, and covered it all with a small upturned plastic pot to stop the weather getting to it. So I think I'm good. Looks a bit odd but it's round the back of the house so not many people will see it.

Don't know if there are any regulations regarding length here in Thailand as I've seen rods as short as just 12in. Guess they would be OK if you live in a swamp or over a river, just dangle it over the side.

[rucus7]

I hope everyone is talking about the same thing. A pipe in the ground? Copper rods (solid) driven into the ground are the most common method. I have seen in the past solid copper wire 8 gauge (US standard) laid horizontally 6 inches below grade. Usually 20 feet of wire is used for this method. The size of the service(amps) determines the diameter of the rod or the guage of the wire. A bronze clamp is used to fasten the copper wire to the grounding rod

[david96]

Vertical-type earth electrodes shall be driven to a minimum depth of:

In Australia 1.2m ( AS/NZ3000).

Material steel. Copper clad/copper plated/stainless(clad) 12mm circular rod.

Hot dipped glalvanised 16mm circular rod.

Earth conductor resistance shall not exceed 0.5 ohms ( from the equipment being earthed to the earth electrode)

Electrode connection must be accessable for inspection and testing. corrosion protection can be by use of a metallic paint.

In your case the earth should be a minimum of 2.5mm stranded copper conductor green/yellow mechanically protected with conduit or cover strip where subject to damage.

As this type of earthing system will not operate a protective device (MCB) in less than 0.4secs with an earth fault so an RCD should be installed.

This type of earthing is common in Thailand very simple and basic if installed correctly and will minimise minor electrical shocks due to leakage currents in equipment.

There are many instances of poorly installed earthing systems thus giving minimal protection.

[BEENTHEREDONETHAT]

The depth of the rod depends on the type of soil it is driven into. You need a moist situation for a good earth contact. In rock or lava it is very hard to make a good grounding rod. In sand it is fairly easy. A rod a couple of metres will make a good ground in normal soil. Very good idea to have one.

[elkangorito]

The depth of the rod depends on the type of soil it is driven into. You need a moist situation for a good earth contact. In rock or lava it is very hard to make a good grounding rod. In sand it is fairly easy. A rod a couple of metres will make a good ground in normal soil. Very good idea to have one.

Are you sure about this?

[Tywais]

The depth of the rod depends on the type of soil it is driven into. You need a moist situation for a good earth contact. In rock or lava it is very hard to make a good grounding rod. In sand it is fairly easy. A rod a couple of metres will make a good ground in normal soil. Very good idea to have one.

Are you sure about this?

If he is referring to being able to drive the rod into the ground then yes, if he is referring to a good conductive ground then no. Sand (dry) is an excellent insulator. Different techniques are required for grounding in a desert for example.

[david96]

With direct earthing or using the IEC TT system the earth resistance of the ground (soil/sand etc) is too high for any fault current to operate a protective device. For this reason an RCD must be installed so as to comply with the fault clearance times.

With the MEN (TN-C-S) system the fault current returns through the neutral to the transformer, a low impedance path, and not through the earthing electrode.

In dry sandy areas other alternative measures may be taken such as running a separate earthing conductor back to the source of supply as well as installing a vertical electrode or strip type earth electrodes in a horizontal trench.

[BlackGrape]

Buy a small multi meter and check continuity 5m then 10m away from the ground spike(as per 16th Edition I think but cannot remember distances). You will need to have another spike to test this.

This will give you peace of mind about your ground continuity. Even better would be to get an Earth Loop Impedence tester and check your earth. This should be compulsory in Thailand as it is in the UK. Every facility I ever went to I always tested this to show the customer.

Hope this helps

[BlackGrape]

Guys

Following my previous post, the connection should not be uner the ground. In UK they are called "earth pots". In Thailand a plant pot under level of ground would do. Smear the connection in coppaslip and then put denso tape(Waxy tape, not sure if available in Thailand). Amalgamating tape would be ok around connection.

Cheers

[Forkinhades]

oh here we go again , please look at this topic where I have explained everything, and indeed attached a file with all the relevant information

http://www.thaivisa.com/forum/German-thai-...02#entry3242502

[Forkinhades]

I just hammer them into the ground till there are about 3in showing and connect the wires and leave it at that.

Just been reading the instructions for installing a hot water shower and it says the top of the rod should be about 70cm below ground level.

Does it really matter? I would have thought with the wire connection above ground where you can keep an eye on it would be better.

For those interested I've got a one and half meter rod in the ground right near the toilet outlet thingy so that should give a good earth connection

If you value your life then indeed it does matter

[BlackGrape]

Sorry Mate, I don't read every thread on TV. You having a bad day?

[Forkinhades]

@ blackgrape indeed I am not, could not be in a better mood. , it just amazes me that people with a little knowledge, can put other peoples lives at risk, these earth rods installations should really be left to the experts, and the meter you need to test them properly and make sure everything is working fine will cost from £600 upwards. The important thing to remember is the time it takes to trip the RCD under fault conditions. As per my posts in the other subject.

[trogers]

Did a star point earthing system for a sub-station of Shell refinery in Malaysia. Specifications was to 1 ohm. Soil type was firm clay. Bored 3 holes (10cm dia) 8 feet deep, fill them with charcoal/sand mix and hammered in three 1.5m copper rods to form the apexes of a triangle and connected them up to a common point. All cabling ran in concrete trenches filled with sand and covered with precast concrete slabs.

[BlackGrape]

Glad you having a good day. Is it me with little knowledge?

Have you seen an Earth Loop Impedence tester in Thailand? I went onto RS online a few months back and the kit is 100,000 baht up. This would stop all this worrying about everybodys earths. Takes 2 minutes to do the test. Crazy why it's not done.

What do you think?

[Forkinhades]

Glad you having a good day. Is it me with little knowledge?

Have you seen an Earth Loop Impedence tester in Thailand? I went onto RS online a few months back and the kit is 100,000 baht up. This would stop all this worrying about everybodys earths. Takes 2 minutes to do the test. Crazy why it's not done.

What do you think?

lol, no just reading the posts, 2 minutes to do the test? remind me not to work for you peace brother

[BlackGrape]

haha, 100%. plug it in and press the button brother

[Forkinhades]

haha, 100%. plug it in and press the button brother

so how do you plug it into the earth rod then? I have done these tests extensively for O2, T-mobile, and the London Underground, and I can assure you the testing of the earth rod which needs to disconnected from the fuseboard takes longer than just plugging in and pressing a button. In fact the right equipment has 4 leads, so where do they all go?

[BlackGrape]

Ah, noted. I'm talking about testing the Earth Loop Impedence for the whole house. Some houses do not have an earth spike. This is a general test that can be done in any electrical installation. Firstly, the test must be done with all normal power on. As per 16th Edition every circuit has to be recorded for ELI. The main test is at the incomer. The ELI tester sends a fault through the line ( thats why you do not use them through RCD's (Been there, done that when serving my time and had a lot of angery architects... Haha). I can't remember the reading but 0.5 ohms comes to mind (acceptable). It finds the lowest path of resistance to earth and gets the reading. I would like to copy the regs and tester specs but kikiet!

If testing individual circuits, the ELI test determines what type of fuse used. MCB, HRC etc. Different fuses for different test results. Can't remember but if more than 5 ohms for a 1.5mm circuit then it needs to be an HRC fuse. The more longer the run (not only resistance but how good the ELI test is at source) always gives a higher ELI reading.

I'm not sure if we are talking about the same things here but I really believe if this tests are done in Thailand then all earthing issues would go away.

Good to have this discussion, please hope you give me your opinion.

Cheers

[Forkinhades]

Ah, noted. I'm talking about testing the Earth Loop Impedence for the whole house. Some houses do not have an earth spike. This is a general test that can be done in any electrical installation. Firstly, the test must be done with all normal power on. As per 16th Edition every circuit has to be recorded for ELI. The main test is at the incomer. The ELI tester sends a fault through the line ( thats why you do not use them through RCD's (Been there, done that when serving my time and had a lot of angery architects... Haha). I can't remember the reading but 0.5 ohms comes to mind (acceptable). It finds the lowest path of resistance to earth and gets the reading. I would like to copy the regs and tester specs but kikiet!

If testing individual circuits, the ELI test determines what type of fuse used. MCB, HRC etc. Different fuses for different test results. Can't remember but if more than 5 ohms for a 1.5mm circuit then it needs to be an HRC fuse. The more longer the run (not only resistance but how good the ELI test is at source) always gives a higher ELI reading.

I'm not sure if we are talking about the same things here but I really believe if this tests are done in Thailand then all earthing issues would go away.

Good to have this discussion, please hope you give me your opinion.

Cheers

Firstly I work to 17th Edition, and in fact the first test you do is with the power off and do insulation resistance, anyway not going to get into that, secondly this is thaivisa, and so we are talking about thai dwellings where 95% of the time there will not be an earth at any accessory, so it is not a case of just plugging in.

I would never put a lighting circuit on a HRC fuse, if the reading was 5 ohms, then it should be investigated further although this would pass if you was put it on a 6 amp MCB which you are allowed 6.13 ohms

[BlackGrape]

I fully agree that only 5% of thai dwellings have a proper earth. If you value your life or family's life, this should be looked into. Tell you the truth, I rent a house and never looked into if I have an earth..haha

Maybe I will buy the kit for 100,000 baht and check everything. The only problem I see is junction boxes where the are not accessible. These would be the only problem. Thats why you need all the kit to correctly test a house for everything. Thai houses have no hatches, lofts etc.

Have you tested your house?

Cheers

[Forkinhades]

I fully agree that only 5% of thai dwellings have a proper earth. If you value your life or family's life, this should be looked into. Tell you the truth, I rent a house and never looked into if I have an earth..haha

Maybe I will buy the kit for 100,000 baht and check everything. The only problem I see is junction boxes where the are not accessible. These would be the only problem. Thats why you need all the kit to correctly test a house for everything. Thai houses have no hatches, lofts etc.

Have you tested your house?

Cheers

yes tested my house, and it has hatches and loft space, earth rod and a dual RCD distribution board. I would not test at junction boxes anyhow, as you need to test from the last point of each, and every circuit

[BlackGrape]

haha, maybe you designed your own house. Can I see the report?

[Forkinhades]

haha, maybe you designed your own house. Can I see the report?

what for?, dont have to prove anything to you buddy

[Forkinhades]

@ blackgrape, when I get 5 minutes I will dig out the file, and pm you, anyhow off to BKK now