Homemade method of measuring earth resistance

Hello. I am modifying the home installation a bit and hence the question. While I can handle the measurement and can handle it, I need to measure the earth resistance. I don't have any specialized equipment at the moment. Any advice?

Do you have an ipz meter?

You can measure the static value of the earth resistance using the technical method.

kisses
- GIFT-

kj1 wrote:

Do you have an ipz meter?

Ammeter + voltmeter + 2 kW load. Measurement of voltage without load, then voltage and current with load. then it's Mr. Ohm's law and calculations.

Darom wrote:

You can measure the static value of the earth resistance using the technical method.

Can I have a description, please?

Maybe I'll explain the topic.
At the moment, I have ONE copper circuit of 1.5 mm square on which hangs a kettle, washing machine, dishwasher and thermal bath. sometimes the oven. Happy what? It used to be like this ...
From the seat post to the meter I have 2x10mm square meters of copper. I leave the circuit that I described only for lighting, I run new three socket circuits. Of course, 3x2.5. Would use EP. I have an old pipe from a filled well. It is not connected to anything, just a piece of galvanization sticking out in the basement, the rest of which (about 10 m) sits in the ground. There will be expansion in the spring, there will be a border. for now I have to rely on what I have. So when I do the pen (TN-C) separation, I will go down from the gsu section in the basement, taking into account the measuring connector along the way. I will connect the GSU with this pipe. All connections LGY 10. After completing the work, I would like to measure this EP. I have several ammeters and AC voltmeters. I would like some advice.

kortyleski wrote:

I would like some advice.

You will need a small transformer, voltmeter and ammeter for your work.

kortyleski wrote:

At the moment, I have ONE copper circuit of 1.5 mm square on which hangs a kettle, washing machine, dishwasher and thermal bath. sometimes the oven. Happy what? It used to be like this ...

What type of distribution network - connection conditions.
Tell me what you are up to.

I once read about a patent somewhere in radio broadcasters to check the earth electrode, you need to connect a 100W bulb. Earth electrode - light bulb - phase how much truth is I do not know. Have any of you heard about such a patent? Heard, read?

CYRUS2 wrote:

What type of distribution network - connection conditions.

kortyleski wrote:

So when I do a pen separation (TN-C)

zdzisiek1979 wrote:

I once read about a patent somewhere in radio broadcasters to check the earth electrode, you need to connect a 100W bulb. Earth electrode - light bulb - phase how much truth is I do not know. Have any of you heard about such a patent?

i think to measure the voltage between L and PE and then the same at light load. it should give me an indicative RPE. With resistances of the order of ohms, ipz should not be of great importance

zdzisiek1979 wrote:

I once read about a patent somewhere in radio broadcasters to check the earth electrode, you need to connect a 100W bulb. Earth electrode - light bulb - phase how much truth is I do not know. Have any of you heard about such a patent? Heard, read?

This is the easiest method. But strictly speaking, it is not a measurement of the earth resistance, because

Quote:

The total resistance of the transformer windings, wires, tested earthing and the neutral point earthing of the supply network are measured then. If the earth resistance, measured in this way, does not exceed the permissible value, then the tested earth resistance is acceptable. "

quote from page 7 Link to Principles of earthing measurements and evaluation of measurement results - Arrow

kisses
- GIFT-

What is the grounding resistance to the short-circuit loop impedance in the TN system ???

kortyleski wrote:

So when I do a pen separation (TN-C)

Measuring is checking.
A question to my friend Kortyleska.
The question is which results (?) will be bad and which will be good.

In principle, PE needs only an additional protection such as RCD. So if it meets this condition with a tenfold margin, it will still be enough. And it is known that the less the better.

However, I still have a technical question. Can the rim and gsu joint located outside the building be treated as a measurement joint or should it be introduced separately from gsu?

A short-circuit loop in a properly made TN-CS is completely metallic (L-PE and PE, after all, "comes out of" the PEN in TN-C).

What specific condition does the colleague want to check?

And I propose to find out what influence the TN earth electrode has on the SWZ
It's best to draw a diagram of the installation with cameras and think how the electricity will flow.
We can subject this pattern to a constructive analysis

elvis13 wrote:

A short-circuit loop in a properly made TN-CS is completely metallic (L-PE and PE, after all, "comes out of" the PEN in TN-C).

Supposedly true, but it would aim at treating PE as a working conductor and it is not ... But thanks for paying attention, the IPZ will be extended with connectors at the PEN distribution in the switchgear.

elvis13 wrote:

What specific condition does the colleague want to check?

What current will flow with a direct connection of L and my improvised PE.

To the point
I will implement the basic protection through the SWZ. After the measurement of the IPZ, I will decide which apparatus to choose so that the condition is met. AT DIRECT JOINT L with any conductor that ends in the switchgear and is not L. because I have PE and N connected, it will work. But PE is not a work conductor.

elvis13 wrote:

It's best to draw a diagram of the installation with cameras and think how the electricity will flow.

I have it in my head for a long time.

For thought, let's assume RPE = 200 ohms, IPZ at B16 meets the conditions of SWZ.

Let us consider three cases. Of course there is a 30mA RCD.

1) What apparatuses will work and in what order when there is a direct short-circuit L to PE (housing) in the device - let it be a washing machine.

2) What devices will work when there is a slight damage to the insulation, or turn off the power warning me about the problem? We are talking about leakage currents that can be dangerous and will not trip the B16 circuit breaker.

3) What devices will work when the PEN on the pole is burned or the neighbor's spruce breaks and this PEN breaks?

elvis13 wrote:

And I propose to find out what influence the TN earth electrode has on the SWZ

no ...

However, I still have a technical question. Can the rim and gsu joint located outside the building be treated as a measurement joint or should it be introduced separately from gsu?

elvis13 wrote:

It's best to draw a diagram of the installation with cameras and think how the electricity will flow.

kortyleski wrote:

I have it in my head for a long time.

Use the advice of your friend Elvis13.

kortyleski wrote:

What devices will work and in what order when there is a direct short-circuit L to PE (housing) in the device - let it be a washing machine.

Only one - which one is a random option.

kortyleski wrote:

What cameras will work when there is a slight insulation damage, or turn off the power warning me about the problem? We are talking about leakage currents that can be dangerous and will not trip the B16 circuit breaker.

No leakage currents in the TN installation are dangerous to the user.
Even those of the order of 5A.
The grounding has nothing to do with it.

kortyleski wrote:

What cameras will work when the PEN on the pole is scorched or the neighbor's spruce breaks and this PEN breaks off?

You have installed some PEN break protection - no.
So no other protection will work.

kortyleski wrote:

I will implement the basic protection through the SWZ.

Does a colleague know what basic protection is?

kortyleski wrote:

1) What apparatuses will work and in what order when there is a direct short-circuit L to PE (housing) in the device - let it be a washing machine.

Let a colleague check with what current and at what time they turn off individual devices.

CYRUS2 wrote:

kortyleski wrote:
What cameras will work when there is a slight insulation damage, or turn off the power warning me about the problem? We are talking about leakage currents that can be dangerous and will not trip the B16 circuit breaker.
No leakage currents in the TN installation are dangerous to the user.
Even those of the order of 5A.
The grounding has nothing to do with it

Of course there is no Grounding. But in the case of 30 mA leakage to the housing, and therefore also the PE conductor, the RCD will be activated. Same as PEN burnout, but only with efficient grounding.

Gentlemen, to the point. I asked for a measurement connector that will also be a connection between the GSu and the wrapper.

kortyleski wrote:

But in the case of 30 mA leakage to the housing, and therefore also the PE conductor, the RCD will be activated. Same as PEN burnout, but only with efficient grounding.

Not true. It will also work in the absence of an earth electrode.
In both cases.

CYRUS2 wrote:

kortyleski wrote:

But in the case of 30 mA leakage to the housing, and therefore also the PE conductor, the RCD will be activated. Same as PEN burnout, but only with efficient grounding.

Not true. It will also work in the absence of an earth electrode.
In both cases.

Sorry, I was thinking fast on the train. With a break in the pen, the RCD will not work by itself. However, in the case of a break in the pen and leakage, it will only work if the grounding is in working order. In the case of a functional PEN and a leakage of current to the device housing in the first protection class, the RCD will also work, even without grounding. Unless the L-PE breakdown is so "strong" that whatever it wants first, RCD or B16 works. Or both.

kortyleski wrote:

However, in the case of a break in the pen and leakage, it will only work if the grounding is in working order.

Will work without an earth electrode.
You do not have a buddy installation scheme in your head or on paper.

As a result of a break in PEN, you will lose some RTV and household appliances.

The installation is single-phase so I won't lose it. In the event of a pen interruption with the rest of the installation in working order, the leakage current will close in the L-RCD - device - PE - distribution point - ground circuit. The RCD will work.

CYRUS2 wrote:

Will work without an earth electrode.

And by what circuit will the differential current flow?

As usual, the user does not provide complete data - a polemic pointless.

kortyleski wrote:

The installation is single-phase so I won't lose it.

Single-phase installation - you are writing only now.

kortyleski wrote:

In the event of a pen interruption with the rest of the installation in working order, the leakage current will close in the L-RCD - device - PE - distribution point - ground circuit. The RCD will work.

This is a completely pointless coincidence.
If the device is faulty, the RCD will trip even before the PEN break.
These are the consequences of the lack of patterns.
In the event of a PEN break, a voltage will appear on the housings of efficient devices.
The RCD will not trip due to the PEN interruption alone - there is no reason.

It will also not work in the event of electric shock from the housing - because the currents in the RCD are reset.
There will be no "hypothetical" shock from the housing in proper installation.
Because the to-ground resistance is very high. (circuit resistances)

Protection against a PEN break would make sense by using a controller that responds to a voltage drop in the network.
The voltage on the casings will appear only when any receiver is turned on.
If the voltage on the receiver is above 190V (230-190 = 40V), it means that the voltage on the housings is not a threat.
If the voltage is lower - the controller switches the phase off - the threat will disappear.

You can theorize for a long time. At the moment, I have asked a specific question and I want to know the answer.

Okay, he's got a lot of embarrassment. Before that, after consulting with a local electrician, I was pretty sure about tn-c. After a telephone conversation with the technician at the supplier, I received an assurance that it was so. Now, in connection with the change in power, etc., I was personally and in the conditions I have tt! Theoretically, it does not change much, the installation is slowly becoming three-wire. It's nice but .. In many more sockets there is still a reset that an electrician once committed. Somehow it doesn't suit me. The second thing is the grounding mentioned in the topic, what should be the value?

kortyleski wrote:

You can theorize for a long time. At the moment, I have asked a specific question and I want to know the answer.

You don't hang?
Put the layout on the table and check it out.

Hello! The main earthing bus in the switching station is led out of the reinforcement of the strip footing. I created the installation myself. I was sure that such a solution was reliable, especially since the differentials work normally. Even when the esach was turned off, I was rummaging around in the socket and I think I shorted N with PE, the RDC worked. Today I had an electrician at my place of measurements, which he made for the acceptance protocol. He would stick a meter into every socket in the house and measure something, then take notes. I thought he was measuring the continuity of the insulation. RDC also tested this meter and said it was very good. Usually it showed him on the meter within 14ohm. What was my surprise when, after a few hours, I learned from his boss who was supposed to create a protocol that I had ineffective grounding.
What should be the resistance value to meet the standards?
If I don't correct it, I won't get the protocol. I live on sandy ground. I'm afraid that when I start knocking pins in, it will still be below normal. And the measurement guy will start to delete me for subsequent commutes and measurements.
After checking according to the above recommendations, that is (voltmeter + ammeter + kettle ~ 2kW) between one of the phases and my footing I have 159V and 5.9A + 50m of 2.5mm? extension cord, with which I pulled the phase from the switchboard differential to the basement. I do not know if I counted correctly, but I get 26.9ohm from where then the 14ohm? How to measure it roughly, so that some dodger from the cash register does not milk me? After all, I will not buy a meter for one earthing system for 600 PLN.

slim24 wrote:

What should be the resistance value to meet the standards?

For surge protection purposes, the required earth resistance value is recommended to be below 10 ohms, but there are exceptions.
For the purposes of protection against electric shock, for the TT system - as the described measurement result suggests - the issues depend on how the protection is provided.
If it is protection using only overcurrent switches - then for a device, eg B16A, it will be a value below 2.875 ohms (for the entire fault loop), with correction factors not taken into account.
If protection is provided by an RCD, then this value is already significantly greater - theoretically permissible for an RCD of 30mA is 7666 ohms.
For the TN system, this value does not matter as long as the earth electrode is properly made.

From what I realized, TN-C comes to me and I already have TN-CS in the switchboard. Even when I buried 5x16mm? in copper from the meter at the border and I connected yellow-green to the PE rail, the differentials did not work, because in the box on the plot border, the yellow-green and blue ones were together. So as in TN-C. I spent a little unnecessary money on an unnecessary 5 wire. Of course, that's what they told me in the power industry that I have to bury the cable 5x.

It's either you can't pinpoint the problem that the tester detected, or the tester measured something wrong.
If the measurement, e.g. in the socket, showed 14 ohms, then the bank does not have a correctly made TN circuit in the installation - or you have some damage.

Sorry buddy, but you write so that it is sometimes difficult to understand what you want to convey.

The SWZ measurement on the PE rail in the main board was made?
Probably not.
And it had to be done.
So now let the guy write you exactly and explain what he measured and what is wrong in which place.
Was the surveyor an employee of the company that performed the installations in the building?