My earthing is screwed

[Love4sound]

I had earlier tried to debug this humbug called chemical earthing over there. It is a commercial trick to cheat gullible and ignorant people.

Earth resistance is the resistance at the interface of the soil and the earth rod. (Refer IEEE 80). Very effective earthing is achieved all over the world including India by simply driving the rod into the ground as @stefan wrote above.

The Indian standards go a step further to specify pipe earthing with coal and salt. Pipe cannot be driven into the ground, so you have to dig a pit and in order to restore the conductivity of the soil that has been disturbed, the charcoal and salt helps. The same applies to plate earthing. If you can compact the soil around the earth rod there's nothing like that. You drive out the air and add water when compacting to get back near the same conductivity. You need space to run the compacting machine. But installers do not do this.

These pipe earthing have a funnel on top to pour water and pipe is perforated to irrigate the soil periodically. Substations in dry areas have an irrigation system that the operators operate or they hose them occasionally to wet the earth pits to keep the resistance down.

This chemical earthing is simply a mixture of bentonite clay and some salts to keep the moisture. It is required only in dry areas where you bore a hole and fill with this mixture to make sure the bonding between the rock and earth rod is contiguous. The rod is then inserted into this "chemical". Even if you are able to drive the earth rod with a pneumatic hammer into the hard & dry soil, due to the vibration and voids in the soil, air that is a supergood insulator will enter the interface of earth rod and surrounding soil to form a high resistance earth pit. Hence, the use of "chemical earthing". In most places in India the proponents of this may be selling it just to steal your money. They know you don't know the science behind it.

If you get a few days of rain once in a while, that will keep the conductivity of soil.

Even in Rayalaseema area (in Telugu it means a land of rocks as I under stand) where I built a 400kV substation we could achieve good low resistance with just soil backfill. Just to reinforce, it was a 400kV station not a 415V transformer. The amount of lightning surges, fault currents, Transient over voltages (TOVs), Switching over voltages, EMIs that can trip the system etc. are infinite compared to an audio system we deal here.

That galvanizing is only to reduce the corrosion not to reduce the earth resistance. Again fooling public.

Chemical earthing isn’t expensive and most earthing companies now only offer chemical earthing. I myself wanted to just drive a rod, use coal and salt but no one was willing to do it and I had to do it my self hiring tools and labour. So chemical earthing is the easy way now. Funny thing is I just installed it to prove a point to EB and it’s just laying idle and have not connected my home earthing to it. The electrode is good indeed and should last long. Claims are that copper electrode will last 30-35 years minimum.

No MX imports Chinese cheap products, I can provide evidence but why? Their products aren't that great anyway, just available.

ok import as in entire product or parts. In the power strip box it’s printed manufactured in india and also somewhere in the product description or some product video it’s mentioned made in india for india keeping Indian power condition in mind .

 

[zero7]

@Subbu68 : I really had lot of issues with earthing in my hometown and spent 8K to dig a pit of about 6 feet and install a GI pipe to get proper earthing. Used a bag of earthing soil, charcoal and salt too. What is the recommended length of the rod if we need to just drive the rod in earth to get proper earthing.?
I would like to add one or two more around the house as I have similar issues like Love4Sound. High NE voltage. Also, lightning and thunders. I have installed SPDs near the energy meter. Also installed a RCCB with SPD in the distribution box, which quickly trips during lightning. Although it's pain sometimes to turn it on again, it saves the equipment from lightning.

Being in coastal area, it rains well. Soil is bit dry in the summer though.

 

[Love4sound]

@Subbu68 : I really had lot of issues with earthing in my hometown and spent 8K to dig a pit of about 6 feet and install a GI pipe to get proper earthing. Used a bag of earthing soil, charcoal and salt too. What is the recommended length of the rod if we need to just drive the rod in earth to get proper earthing.?
I would like to add one or two more around the house as I have similar issues like Love4Sound. High NE voltage. Also, lightning and thunders. I have installed SPDs near the energy meter. Also installed a RCCB with SPD in the distribution box, which quickly trips during lightning. Although it's pain sometimes to turn it on again, it saves the equipment from lightning.

Being in coastal area, it rains well. Soil is bit dry in the summer though.

For me only issue was from EB side. My flats earthing, wiring etc none of them had any issues.

 

[Subbu68]

No MX imports Chinese cheap products, I can provide evidence but why? Their products aren't that great anyway, just available.

As far as i know MX is made in india product. Chemical earthing is done using a galvanized electrode and chemical compound.I did it recently. 10 feet hole was dug and a 10 feet rod was put inside the hole filled with chemical compound.

Do MX specify anything technical in their website other than what is on Amazon? They don't specify the energy it can expend. Simply 10,000A, 10,000V and 1microsecond wave front. So it could be just 100 joule (10kV x 10kA x 1microsecond).

 

[Love4sound]

Do MX specify anything technical in their website other than what is on Amazon? They don't specify the energy it can expend. Simply 10,000A, 10,000V and 1microsecond wave front. So it could be just 100 joule (10kV x 10kA x 1microsecond).

Not available but any ways I got it just as a PDU and not for protection.I have connected it to my isolation transformer. Will get something effective later on

 

[Subbu68]

@Subbu68 : I really had lot of issues with earthing in my hometown and spent 8K to dig a pit of about 6 feet and install a GI pipe to get proper earthing. Used a bag of earthing soil, charcoal and salt too. What is the recommended length of the rod if we need to just drive the rod in earth to get proper earthing.?
I would like to add one or two more around the house as I have similar issues like Love4Sound. High NE voltage. Also, lightning and thunders. I have installed SPDs near the energy meter. Also installed a RCCB with SPD in the distribution box, which quickly trips during lightning. Although it's pain sometimes to turn it on again, it saves the equipment from lightning.

Being in coastal area, it rains well. Soil is bit dry in the summer though.

The standard in most places is 3m rod. Deeper you go the soil temperature is said to be stable and drying out is less. There is no specific length. If you reach water table with your rod, the BEST.

If you add more rods around the house, keep a space of two lengths between the rods. The theory is, earth resistance has a sphere of influence that extends to about the radius equal to the length of the rod. Two rods have to be out of each other's sphere of influence. They'd have a mutual effect on each other and resultant resistance will be more than the theoretical parallel value (R/2 or R/3 or R/4...). Parallel them and connect the house earthing to this set of rods.

High NE voltage is not due to earthing issue. A high resistance fault on one phase to Neutral or if you are an isolated house with three phase supply check for unbalanced load. Resulting neutral current causes the neutral to rise with respect to earth.

 

[Subbu68]

Not available but any ways I got it just as a PDU and not for protection.I have connected it to my isolation transformer. Will get something effective later on

check this link

Extension leads

Extension leads

www.brennenstuhl.com

They are in India too. Quite reputed. Since in EU and other countries there are tight regulations, they'd have proper design too

 

[Subbu68]

Not available but any ways I got it just as a PDU and not for protection.I have connected it to my isolation transformer. Will get something effective later on

brennenstuhl® - Selection of themes - Overvoltage protection - Surge currents for extension leads

Discover the brennenstuhl® selection of themes for Surge currents for extension leads!

www.brennenstuhl.com

hope this would give you an idea

 

[zero7]

Thanks @Subbu68 . It's a single phase supply and the issue is not just in my house. Checked in two other houses about 100 m away too.
I did earthing as the electrician had installed a earthing pipe of 2 feet originally and I started getting shocks while using my laptop. Leakage was from the refrigerator which I discarded later.
But driving a 3 mtr rod is not easy without proper equipment.
Just curious, I have an open well and a bore well there. Will it work running a earthing wire until the bottom of the well or to a level where the wire is always immersed in the water. I am sure it's not a recommended or approved method. Lol.

 

[Love4sound]

check this link

Extension leads

Extension leads

www.brennenstuhl.com

They are in India too. Quite reputed. Since in EU and other countries there are tight regulations, they'd have proper design too

Ok will check them out. I was thinking about getting the rontek later on. Check out the specs which seems good

Power Management Systems - Rontek Systems

rontek.in

 

[Love4sound]

Thanks @Subbu68 . It's a single phase supply and the issue is not just in my house. Checked in two other houses about 100 m away too.
I did earthing as the electrician had installed a earthing pipe of 2 feet originally and I started getting shocks while using my laptop. Leakage was from the refrigerator which I discarded later.
But driving a 3 mtr rod is not easy without proper equipment.
Just curious, I have an open well and a bore well there. Will it work running a earthing wire until the bottom of the well or to a level where the wire is always immersed in the water. I am sure it's not a recommended or approved method. Lol.

Where this houses also connected to the same distribution transformer? I recently did chemical earthing using a 10 meter rod by professionals. They just came in one bike with all the required tools and finished digging within 2 hours. They will use a tool called augar. This is a manual device and for more then 10 feet they will use the augar machine fixed to tractor. Shared both link for you to get an idea. If you are sure earthing is at fault contact a professional and get your earthing done. Should be an easy task for them. I was also paranoid how 3 meter deep pit will be dug but they finished the work easily within 3 hours.

 

[zero7]

Where this houses also connected to the same distribution transformer?

Yes, all the houses in the vicinity are connected to the same transformer which is about a KM away.
Thanks for sharing the auger details. I need to look for such services next time.

 

[Love4sound]

Yes, all the houses in the vicinity are connected to the same transformer which is about a KM away.

Then I don’t think earthing alone is the problem for your N-E voltage problems.Disconnect the load and take readings directly at the distribution box. This will give you an idea if the fault is at your end or the distribution transformer.

 

[zero7]

Then I don’t think earthing alone is the problem for your N-E voltage problems.Disconnect the load and take readings directly at the distribution box. This will give you an idea if the fault is at your end or the distribution transformer.

NE leakage is not due to earthing in my house. It is a common problem from the transformer itself.
Only thing I could do is fix the issues what I found in my house. There were few more issues also with the wiring. Electron hadn't segregated the neutral wires for power plugs and lights until the distribution box. I found many issues with the wiring after adding a RCCB in the distribution box. Unfortunately, these electricians take shortcuts and put people at risk. For them, "look, the light is on, fan is running fine", their job is done.

 

[Love4sound]

NE leakage is not due to earthing in my house. It is a common problem from the transformer itself.
Only thing I could do is fix the issues what I found in my house. There were few more issues also with the wiring. Electron hadn't segregated the neutral wires for power plugs and lights until the distribution box. I found many issues with the wiring after adding a RCCB in the distribution box. Unfortunately, these electricians take shortcuts and put people at risk. For them, "look, the light is on, fan is running fine", their job is done.

I hear you. What is EB excuse? Have you met the AE and submitted a complaint? I gave up and went with an isolation transformer which solved my issues. And after a week of getting an isolation transformer EB fixed my issues thanks to the pressure given by another locality AE who happens to know my mom. You can also get an isolation transformer just for your system.

 

[zero7]

I hear you. What is EB excuse? Have you met the AE and submitted a complaint? I gave up and went with an isolation transformer which solved my issues. And after a week of getting an isolation transformer EB fixed my issues thanks to the pressure given by another locality AE who happens to know my mom. You can also get an isolation transformer just for your system.

EB is only responsible for voltage between phase and neutral. One day there was 388V supply due to some tree falling on the lines and when I called, they told me that, you are the only one person complaining. There is no issue. Lineman came and disconnected wires at my meter saying that the fault is in my service wire. This is the kind of EB I have to deal with. I gave up talking to them as well.

 

[Love4sound]

EB is only responsible for voltage between phase and neutral. One day there was 388V supply due to some tree falling on the lines and when I called, they told me that, you are the only one person complaining. There is no issue. Lineman came and disconnected wires at my meter saying that the fault is in my service wire. This is the kind of EB I have to deal with. I gave up talking to them as well.

Well seems like EB is absolute garbage every where. I also faced the same issues with them. You need to meet the AE in person and convince him. If don’t mind spending you can invest in an isolation transformer for your entire home. This will solve the N-E issues. Calling them and speaking with line man is of no use. Reach AE personally

 

[Subbu68]

My water table is at least 4m down, honestly i believe 1 metre would be enough, but I'm not an electrical engineer, in fact I've seen them driven less than a metre in the UK ( I will state the uk has the best electrical system in my opinion)

UK, EU and Western countries have very high standards when it comes to electrical engineering (as well as others). There are strict regulations and standards that the utilities and users have to follow. Middle East too have adopted UK and IEEE standards. It is not that Indian standards are bad, but a lot of short cuts and the installers do not heed to the requirements - be it be wiring or earthing or any other installation.

I have seen in Punjab the HV supply is connected and disconnected using wires with stones tied to them not a proper isolating switch. The wire is pushed out or put back with a bamboo pole

Coming back to earth rods, the length of the rod required depends on the earth resistivity and the depth at which it is low. Earth Resistivity is measured by what is called Wenner method. Maybe 3 point or 4 point as in first picture below. The principle is you inject current into the earth and measure the voltage between two points starting at say 1m between each other. Then vary the spacing for more readings.

The earth tester is calibrated to read in Ohms than voltage. Resistivity is calculated with a formula from IEEE80. If the reading is consistent when you measure varying the distance between the probes that is the earth resistivity to consider. The spacing from where the reading is same indicates the depth of stable earth resistivity.

Using this they calculate the earth rod length, resistance etc. for an earthing system. For large installations it is measured in 4 or even 8 directions to cover the plot. There can be geological variations across the plot.

See below table for a measurement in 4 directions.

• Set A is consistent or up to nearly 5m resistivity is same.
• Set B is again nearly the same through out.
• Set C you can see the reading drastically drops from 2.3m indicating the resistivity is high in top layers of the soil in that direction.
• Set D it starts rising after 1.5m indicating rock below that depth.

These readings are fed into a modelling software and a common resistivity for design is arrived. That is the engineering way.







Now for the common man, the general soil conditions will be known when you construct your house or dig well. There are also approximate values of resistivity for various soils in the engineering standards that engineers use.

If you strike water say at 2 or 3m it will be safe to drive a rod to that depth. Abandoned wells could be used. Utilizing wells in use might be a risk to humans and animals. For a short circuit, the area around could have a high potential and lead to electrocution. It is advised not to use water pipes as these could pose the same danger.

In UK it being wet climate and soil being clayey, you get low resistance at very low depths so longer rods are not necessary. Still, I think they use 1.2m rods.

3m rods are difficult to drive but they do it in India where 25mm dia MS rods are generally used (due to theft). Copper lasts longer due to better resistance to corrosion when in soil than steel.

With commercial earth rods you get in convenient lengths like 1.2m and couple rods with metal couplers to extend them. So you drive a 1.2m and when it is in the soil couple the next, drive it in and so on.

All that augur and chemical earthing is at least not for me. It does not enhance anything if the soil condition is good. And chemical earthing system will deteriorate if you don't maintain it by occasional watering or it does not rain. The bentonite like any clay will shrink when it looses moisture due to heat and the earth rod will have air gap at the interface leading to high resistance.

Hope I could bust some myth around earthing.

 

[Love4sound]

All that augur and chemical earthing is at least not for me. It does not enhance anything if the soil condition is good. And chemical earthing system will deteriorate if you don't maintain it by occasional watering or it does not rain. The bentonite like any clay will shrink when it looses moisture due to heat and the earth rod will have air gap at the interface leading to high resistance.

Hope I could bust some myth around earthing.

But Chemical earthing is marketed as maintenance free earthing.

 

[Subbu68]

But Chemical earthing is marketed as maintenance free earthing.

It is wrong.... absolutely wrong..it will absorb moisture from surrounding soil if conditions are good. Or will dry out . Simple thermodynamics..

You must have seen fields or river beds drying up and cracking in summer? Same thing happens with this earthing fill too