Earthing Significance in Domestic Wiring

I'm just curious, where is this, that you have seen salt and water put in an 'earthing pit'? I'm not familiar with that. All residential earthing around here is accomplished with copper clad rods (I think 8 feet long) driven into the ground, and they serve as the neutral and the ground.

Your in the USA. I'll bet the OP isn't.

Maybe he should put the earth pit under the outhouse.

My feet have trodden foreign soil and my screw driver has done its work in many lands.

You are correct about my location. I have however, seen the problem the OP refers to and am passing familiar with the issues involved.

In one country I visited, it was very common to use only one leg of the 220~240 VAC provided and use a ground return when one wanted to steal electricity. It seems that the national power utility in this particular place only measured power on one conductor of the 220 VAC feed to the subscriber. This meant that the other conductor would give a somewhat spongy 110~120 VAC to earth with no power use shown on the meter.

In these installations, the voltage was prone to vary with the return (earth) resistance and the house load.

The typical power thief installation included a multiple tapped auto transformer to increase the voltage back to 220 for internal use. Some of these were hand switched, others were auto adjusting. Even the automatic adjusting type would run out of switching taps and go out of regulation if the load got too high or the earth connection got too dry.

I saw all of the light bulbs in a restaurant blow out simultaneously when someone dumped a pot of dishwater on the ground rod one evening. It takes a little time for the tap switching transformer to catch up when the voltage changes suddenly ;-/

73 DE TT3

So in that country they didn't use an earth leakage circuit breaker?

If they had used "an earth leakage circuit breaker", they wouldn't have been able to use earth for a return power now would they?

Hi

That is genius to put "earth" pit under outhouse , and salt is specially for those who have diabetes symptoms to "neuteralize" the path. However the normal patients can use only water.

Have fun.

IMO, in a normal, meaning wired to code installation, earthing has nothing to do with low voltage unless there is a fault to ground.

In any number of jack leg, rigged up, dangerous as Hell, installations where earth is used as the return path for a branch circuit, a poor earth connection puts a variable resistance in series with the load. If you have to water your earth connection to keep the lights on, someone is doing something seriously, dangerously, deadly, most probably illegally wrong.

If you are dealing with one of these unsafe lashups, salting and wetting the earth connection reduces the resistance in the return path, which brightens up the lights and speeds up the fans.

TT3

p.s. urinating on the earth connection, ground rod will most likely result in your internment into said ground due to ELECTROCUTION. Get away from this place quick if you want to live!

There is one situation where the earth return is legally used in Australia. in outback conditions where the generation may be 100s of km from a building they use a SWER (Single Wire Earth Return) system to minimise the costs of running multiple wires. These installations are typically around 22kV lines with a transformer at the installation end to bring it down to the standard 220v. One side of the transformer is run to ground and the installation is also earthed via copper clad rods driven into the ground. This system works quite well and for places where the particularly arid nature of the land makes ground resistance high a second wire can be run from the installation to the transformer earth to tie them together. It's not a practical solution for heavily populated areas or the electricity thieves where the normal system is run but it does provide those in remote places a supply that they might not otherwise have.

I am also curious to know how voltage is connected with earthing.

But the reason for putting salt and water in earthing pit is to keep the soil wet and to improve the efficiency of earthing system as i know.

Your question was well answered in post #2. The ground only affects the voltage when the earth (ground) connection is used for the return path of the circuit.

If the earth connection is used as part of the load circuit either by fault or intention, the quality of the ground determines in large part, the series resistance between the source and the load. This series resistance will cause the voltage across the load to decrease as the load current increases. (See Ohm's law for an explanation of the phenomenon.) The resistance also decreases when the quality of the earth connection is improved by salting, watering or by putting in multiple parallel ground rods.

Those who boost system voltage by salting the earth pit would appear to be the same ones that are using the earth conductor as the neutral return path incorrectly, and potentially (no pun intended) dangerously.

Read the Wikipedia article on earthing systems, and change all domestic wiring that does not use the neutral return conductor before any resident gets hurt/killed.

I would guess that you only have a two wire mains, similar to the Australian outback and South Africa......

There are EEs here from Oz that can help you far better than I can........best of luck.

"Earthing" (or "Grounding") gives a reference point so that the system "knows" where zero Volts is.

He answered his own first question, you printed only part, you should have printed more like this:-

What is the significance of earthing in domestic wiring? What I know is earthing is used for protection purpose but I have heard many times that if voltage is dim in domestic single phase supply people talk about earthing system.

All that was left is the part about the earth pit/connection!!! That's what we all were answering!!!

The ground is for safety, but not from lightning. Before grounds were used if the hot wire in your drill came in contact with the metal casing nothing would happen....until you (properly grounded - let's say barefoot on wet grass) became the ground by picking up the drill (lets say your hands are wet too!) You would get a dose of current up to what the breaker, fuse, wire, or your body, could handle.

With a grounded appliance, (plugged into a outlet that really has a ground wire) when that hot wire's insulation wears thin and comes in contact with the metal housing, all hell will break loose, sparks flying, light dimming, and ultimately (hopefully) a fuse or breaker would pop. All of this would prevent you from involuntarily becoming the ground.

So 'Grounds' are to help blow fuses and trip breakers!

GA

As you correctly said, as good as nothing to do with lightning......

Now what "Guy" was it here setting "bad standards"? Come on own up!!!

I agree with the safety ground as described by Barcshetta, but it's also for lightning. At my age do you expect me to remember all the right answers? In the National Guard I was in Field Communications. At summer camps we had a switchboard for the perimeter defense telephone system. It had to have a ground rod for lightning protection. What's with you guys, I give a good answer and get kicked 3 times. OK, it says it is "to minimise the likelihood of direct lightning strikes to the phase conductors". But if lightning did strike, it would give a place for the current to flow. Do you not agree with this? Anyway stop kicking me while I'm down!

Even what you imply here is not correct.

The lightning strikes usually hit the cables hanging from telephone/telegraph poles/power lines. To stop the lightning shock entering a building via these wires, you have special semiconductors that bridge the high voltage to ground when required. So you need a good ground for that reason alone.

All buildings in the world with telephone/power lines need such precautions. Though in my experience, the power line surges are often completely ignored.

It is recommended to not use a standard "wired" telephone when an electrical storm is nearby, or at least that used to be the case.....

Grounds are more important for electrical safety.

But in fact a "ground" makes itself "more attractive" for lightning strikes simply because its a ground (where lightning strikes sometimes start, from ground to sky I mean), so its a good idea to have proper lightning conductors over a building so that the two cannot meet!!!

Some people ask, does a strike start from the cloud or ground?

The answer is both. Cloud-to-ground lightning comes from the sky down, but the part you see comes from the ground up. A typical cloud-to-ground flash lowers a path of negative electricity (that we cannot see) towards the ground in a series of steps. Objects on the ground generally have a positive charge. Since opposites attract, an upward streamer is sent out from the object about to be struck. When these two paths meet, a return stroke zips back up to the sky. It is the return stroke that produces the visible flash, but it all happens so fast - in about one-millionth of a second - so the human eye doesn't see the actual formation of the stroke.

Taken from:-

http://www.nssl.noaa.gov/primer/lightning/ltg_basics.html#

"Even what you imply here is not correct."

I didn't imply anything. I gave a direct quote from one on the links which you obviously didn't read. I believe the top wire on power poles is the grounded one (a ground wire comes down every so many poles to a ground rod). Because it is on top, the lighting is intended to strike it so as to avoid the "hot" wires.

I am not minimising the importance of a safety ground in the home. Many older US homes have only the 2-wire outlets. I would not buy such a home, but I grew up in one.

You are obviously someone who has a character defect in always needing to be right, one way or another.....

Trouble is you are not right.

I have no further interest in trying to explain it or argue with you either.....

Stay the way you are.

Bye.