Payment for electricity makes up a significant share of our utility costs. This is not least due to the widespread proliferation of household appliances and electronic devices. Since the specific payment amount depends on the meter readings, I would like the accounting data to be reliable.
How do you know if your meter needs checking?
Checking the electric meter is necessary if you notice the following phenomena:
- Significant increase in electricity consumption compared to previous months, although you did not buy any new electrical equipment. In addition, you have no reason to attribute the increase in consumption to seasonal characteristics (longer artificial lighting in winter).
- There is no reduction in electricity consumption after you are away for a long time, for example, during a vacation.
- The volumes of electricity consumption are generally not comparable with the power of existing equipment.
In these cases, it is necessary to check the metering device if you do not want to overpay. In addition, the check can be carried out for preventive purposes, even without obvious signs of problems.
Our goal is to establish a match (or discrepancy) between actual electricity consumption and meter readings.
Let's look at how to check the electric meter at home without resorting to outside help:
1. Check the connection diagrams. Although this is the very first recommendation, it only makes sense for newly installed appliances or when moving into a new home.
2. Induction electricity meters can continue to work (spinning) even if there is no current consumption at all. You can check the presence of such an effect quite simply: turn off all the machines leaving your meter on the distribution panel, leaving the incoming one on. After this, monitor the condition of the device - if it rotates faster than 1 revolution in 15 minutes, then there is a problem.
3. Use of direct measurements. This is a rather complex method that requires certain skills.
Turn off all consumers and prepare a standard 100 W incandescent lamp (energy saving ones will not work) and a stopwatch. 3-5 seconds after turning it on, start counting the disk revolutions or flashes of the electronic counter indicator. Time 10 rotations or flashes. Let's say it's 112 seconds.
Let's calculate the standard electricity consumption of a lamp for 112 seconds. = 100 (lamp power) × 112 / 3600 (seconds in an hour) = 3.11 Wh.
Now let's calculate the electric meter readings during this time. To do this, we need to know its constant (gear ratio), which is indicated on the front side. Let's say this is 3200 flashes per 1 kWh.
The electric meter reading for 10 flashes will be 10/3200 = 0.00312 kWh or 3.12 Wh.
The instrument error in this case is (3.11 - 3.12) / 3.12 = - 0.003 or -0.3%. Your meter slightly overestimates consumption, but its error is less than 1%. Considering that we used the standard consumption of the lamp, and not the actual one, the result indicates normal operation.
If your error result is significantly higher than 1% (not in your favor), then it makes sense to call professionals for more accurate measurements in order to make an informed decision about replacing the meter.
How to check the operation of an electric meter at home
Why check your electric meter?
Every month, electricity consumers experience increasing financial burden due to rising tariffs. At the same time, it very often happens that the consumer pays for electricity that he does not actually use. This happens due to a faulty electricity meter. To make sure that your electricity meters are working properly, you can test the device at home.
It is necessary to immediately clarify: in a domestic environment, it is only possible to check the metering device, which should not be confused with checking the meter itself. The latter is carried out by institutions that specialize in servicing metering devices, and it has legal force. If a consumer decides to check the correct operation of the electric meter at home, the test results can only reassure him if no breakdowns have been identified, or become a reason to organize an inspection if a significant error is detected.
The meter test can be carried out at any frequency. As a rule, the idea to arrange a check arises in the following situations:
- Energy is consumed in volumes that are not comparable with the needs of the equipment available in the house;
- The decrease in electricity consumption due to the long absence of consumers occurred disproportionately. Sometimes consumption volumes do not decrease at all;
- There was a sharp jump in electricity consumption. At the same time, recently no equipment has been purchased that could significantly increase the amount of energy consumed - bread machines, washing machines, air conditioners. Also, the number of people living in the apartment remained unchanged and it is impossible to justify the jump in electricity consumption due to a change in season, for example, due to the start of operation of heating devices.
Preparation before the test
First, it is necessary to study some points that should be taken into account in the process, especially if the consumer does not know how to check the electric meter at home and determine the accuracy of the readings.
The correct operation of the electric meter primarily depends on whether it is connected correctly. In domestic conditions, a single-phase device with direct connection is most often used. Further, all the nuances will be discussed using his example.
Test equipment
How to check an electricity meter without special equipment? This question is asked by many inexperienced consumers, and the answer will please them: this does not require sophisticated devices.
Usually, for “home” testing, it is recommended to use current clamps. This device is not so easy to get, except from electricians. In addition, apartment wiring is usually hidden in the walls, so this device may simply be useless.
The simplest and most convenient device for checking an electricity meter will be a tester, which is sold in stores and allows you to determine the error of the meter by measurement. You can also use a multimeter, but there is an important point here - in order to confidently use a multimeter to independently test the electric meter, you must first make sure accuracy of the device's readings. Accuracy is tested in the laboratory.
Checking the functionality of a multimeter is a complex and expensive procedure that may be less profitable than a regular test. Therefore, if you use a multimeter, you just need to trust its readings. In addition, the likelihood of a multimeter breaking is negligible due to the specifics of its design.
Self-propelled gun
If the device being tested is connected correctly, you should proceed to determining the presence of a so-called self-propelled device. This word denotes one of the malfunctions in which the device records non-existent electricity. Before checking the accuracy of the electric meter readings, you need to eliminate spontaneous movements of the disk, if any. To do this, you need to turn off all electrical appliances. It is important to remember that you need to turn it off, and not put it in standby mode.
A more correct result will be achieved by turning off the group machines that are located after the counter. However, they are not always present. It is also worth leaving the introductory machine in operation. Under these conditions, the counter indicator (if electronic) should not make more than 1 flash in 5–10 minutes of inactivity, and the induction device disk should not make more than one revolution. The longer this period of time, the better, but it is better to familiarize yourself with the documents supplied with the device, in which this time is indicated precisely.
Next, the reading error is measured. To check the accuracy of the meter, you should use an incandescent lamp and a multimeter. It would be optimal to use the electronic version of the multimeter and not use household appliances as a load. The bottom line is that modern models of household appliances are capable of independently regulating power and therefore, given the use of their nameplate power in measurements, it will not be possible to reliably check the electric meter.
The “control measurement” process looks like this:
- mains voltage measurement;
- lamp current measurement;
- determination of the actual current strength in the lamp;
- measuring the time during which the disk of a meter connected to the network will spin 10 times while simultaneously monitoring the voltage in the network. For electronic models – 10 blinks of the indicator;
- determination of the counter constant, which is usually indicated on the front panel. For example, 3200 pulses/kWh;
- calculation of actual electricity consumption;
- calculation of the current consumed during the test;
- checking the meter for error using the formula 1000 * number of revolutions / meter constant;
- determination of the error value. Permissible error value – up to 10%
If one day the consumer decides to stop the device on which an antimagnetic seal is installed, you should pay attention to the sticker or indicator, which changes color in the presence of magnetization. If inspection authorities notice this, the consumer may face problems.
A counter of a simpler design can be checked as follows. You should take a thin needle and bring it to the panel - if it is attracted, this will indicate the magnetization of the counter. Usually 2-3 days after removing the magnet, this phenomenon disappears. If the magnetization does not go away on its own, you need to use a demagnetizer.
Video “Self-checking the electricity meter”
In this video, a specialist will show you how to check an electricity meter without any available tools.
How to check your electric meter yourself
- The main reasons for checking the electric meter
- Is the electricity meter connected correctly?
- Checking the meter with clamps and a multimeter
- Incandescent lamps for checking the electric meter
- Video
Every facility that consumes electricity must be equipped with an electricity meter. In accordance with the law, the consumer must maintain the electric meter in good condition and monitor its correct and accurate functioning. Therefore, at the slightest suspicion of a malfunction of the device, many owners have questions about how to check the electric meter, whether it is possible to do it yourself or will have to call a specialist.
The electric meter must be checked in a timely manner, since in the event of a malfunction, payment for electricity may be charged at completely different rates, which will inevitably cause significant financial losses.
The main reasons for checking the electric meter
Checking metering devices for consumed electricity must be performed periodically, as planned. However, situations may arise when you simply cannot do without this procedure and you need to solve the problem of how to check the electric meter at home. For example, owners notice a sharp increase in energy consumption, although the number of people and electrical appliances in the apartment remains the same. Electricity consumption may not have decreased during a long absence, or it may have decreased very insignificantly.
In some cases, consumers simply forget about the operation of the air conditioner in the summer and the heater in the winter. Therefore, before sounding the alarm, you need to carefully check everything and pay special attention to operating electrical appliances. Only after this is it recommended to check the electric meter, which can be done in various ways.
Is the electricity meter connected correctly?
Before checking the electric meter yourself, you need to find out whether it is connected correctly. In city apartments, power is supplied through single-phase networks, so it is recommended to consider a single-phase meter as an example.
The conductors are connected through four terminals, numbered 1,2,3,4. The phase wire is supplied to the meter from the main line to terminal No. 1. From terminal No. 2 it goes further towards the premises. Accordingly, the neutral conductor is connected to terminal No. 3, and goes to the premises from terminal No. 4.
In private homes, three-phase meters are often used. Their difference with single-phase devices lies only in the number of wires and terminals. For the two additional phases, corresponding input and output terminals are provided.
If all conductors are connected correctly, you can begin checking the electric meter for correct readings. First of all, the meter is checked for the presence of self-propelling, when the readings increase, even if no electricity is being consumed at the moment. To identify this malfunction, you need to disconnect all current consumers from the network. Group machines located near the meter must also be turned off. Only the introductory machine remains switched on.
The number of revolutions in the induction counter should not be more than 6-12 times per hour. The lower the rpm, the better. Electronic meters count indicator flashes. If the number of outbreaks exceeds 12, you should move on to more serious verification methods.
Checking the meter with clamps and a multimeter
Current clamps are a professional tool and, as a rule, are not purchased for a one-time test. However, it is recommended to borrow it from friends, since this method provides high measurement accuracy.
Electric current, driving household appliances, does a certain amount of work. Therefore, when checking the electric meter for the correctness of the readings, two works are compared: real, actually performed, and calculated, the results of which are shown by the calculating device. The unit of measurement is watt-hours.
The actual operation with a single-phase meter is as follows:
- When checking the electric meter, the devices must be working. To measure the current strength, take the phase wire coming out of terminal No. 2 of the meter.
- At the same time, the voltage is measured. The current is then multiplied by the voltage, resulting in power (W).
- You need to use a stopwatch to measure the time required for 10 revolutions on an induction counter and 10 flashes on an electronic one.
- The power is multiplied by the resulting time in seconds. The result is work measured in Joules. The work value must be divided by 3600, the result will be the actual power consumption (W x h).
In three-phase metering devices, measurements are carried out for each phase, after which all received powers are summed up. Next, you need to determine the calculation work. First you need to find the gear ratio, denoted in meters by the symbols r or A. It shows the number of pulses or revolutions made when 1 kW x h of energy is consumed. In this case, no special measurements are required; it is enough to use the formula A2=1000n/r, in which A2 is the calculated work, n is the number of revolutions during the actual work time, r is the already mentioned gear ratio.
After both work values have been obtained, they need to be compared with each other. The meter can be considered operational if the calculated performance differs from the actual performance by no more than 10 percent. Thus, the question of how to check the operation of a single-phase electric meter can be considered resolved using this method. The technique for checking an electric meter using a multimeter is exactly the same as with a current clamp. This device is considered accessible and relatively inexpensive. Among the disadvantages, it should be noted the lower quality of measurements and the reliability of the results obtained.
Incandescent lamps for checking the electric meter
Current clamps are not always and not everyone can have on hand. In such cases, when deciding how to check the accuracy of the electric meter readings, the best way out would be to use incandescent lamps with a previously known power. As an example, five light bulbs of 100 watts each are taken. That is, their total power is 500 watts.
The verification procedure consists of the following steps:
- First of all, all electrical appliances are turned off without exception. Particular attention should be paid to energy-saving lamps, which are strictly prohibited from being used during the test.
- Before checking the operation of the electric meter, all circuit breakers in the electrical panel must be turned off.
- After this, 5 incandescent lamps are connected to the meter in the circuit.
- Next, time t is recorded, during which the induction device makes 10 revolutions, and the pulse device makes 10 flashes. During the test, a result of 20 seconds was obtained.
- Then the time T is calculated during which one full revolution or the interval between flashes is completed. For this purpose, t needs to be divided by 10 and you get 2 seconds. With a larger number of revolutions taken, the calculations are more accurate.
- When checking an electricity meter, you need to set the value of the gear ratio indicated on the meter as A or r. In the example given it is 3200.
- The lamp power is converted from kilowatts to watts: 500 W = 0.5 kW.
The final calculation of the measurement error is performed using the formula: E = (PTr/3600) x 100. The error E is measured as a percentage. Substituting the available values, we get the following result: (0.5 x 2 x 3200/3600) x 100 = 11.1%. Based on the results, we can conclude that the electric meter is not operating correctly, since its maximum permissible error of 10% has been exceeded. The data obtained should be confirmed by an official audit, the results of which will have legal force.
In some cases, the cause of excessive energy consumption is simple theft from neighbors. There are different ways to identify a thief. The most effective one involves unscrewing the plugs from the shield on the landing and observing it through the door peephole. Sooner or later, left without electricity, a thief will appear to find out what's going on. The only drawback of this method is that it cuts off power to your own apartment for an indefinite period of time.
Checking an electric meter is a set of measures aimed at determining the accuracy of the readings of this device. This article will tell you how to check the electric meter at home, and also discuss some of the nuances of this process.
Every month, electricity consumers experience increasing financial burden due to rising tariffs. At the same time, it very often happens that the consumer pays for electricity that he does not actually use. This happens due to a faulty electricity meter. To make sure that your electricity meters are working properly, you can test the device at home.
It is necessary to immediately clarify: in a domestic environment, it is only possible to check the metering device, which should not be confused with checking the meter itself. The latter is carried out by institutions that specialize in servicing metering devices, and it has legal force. If a consumer decides to check the correct operation of the electric meter at home, the test results can only reassure him if no breakdowns have been identified, or become a reason to organize an inspection if a significant error is detected.
The meter test can be carried out at any frequency. As a rule, the idea to arrange a check arises in the following situations:
- Energy is consumed in volumes that are not comparable with the needs of the equipment available in the house;
- The decrease in electricity consumption due to the long absence of consumers occurred disproportionately. Sometimes consumption volumes do not decrease at all;
- There was a sharp jump in electricity consumption. At the same time, recently no equipment has been purchased that could significantly increase the amount of energy consumed - bread machines, washing machines, air conditioners. Also, the number of people living in the apartment remained unchanged and it is impossible to justify the jump in electricity consumption due to a change in season, for example, due to the start of operation of heating devices.
Preparation before the test
First, it is necessary to study some points that should be taken into account in the process, especially if the consumer does not know how to check the electric meter at home and determine the accuracy of the readings.
The correct operation of the electric meter primarily depends on whether it is connected correctly. In domestic conditions, a single-phase device with direct connection is most often used. Further, all the nuances will be discussed using his example.
Test equipment
How to check an electricity meter without special equipment? This question is asked by many inexperienced consumers, and the answer will please them: this does not require sophisticated devices.
Usually, for “home” testing, it is recommended to use current clamps. This device is not so easy to get, except from electricians. In addition, apartment wiring is usually hidden in the walls, so this device may simply be useless.
The simplest and most convenient device for checking an electricity meter will be a tester, which is sold in stores and allows you to determine the error of the meter by measurement. You can also use a multimeter, but there is an important point here - in order to confidently use a multimeter to independently test the electric meter, you must first make sure accuracy of the device's readings. Accuracy is tested in the laboratory.
Checking the functionality of a multimeter is a complex and expensive procedure that may be less profitable than a regular test. Therefore, if you use a multimeter, you just need to trust its readings. In addition, the likelihood of a multimeter breaking is negligible due to the specifics of its design.
Meter verification methods
Self-propelled gun
If the device being tested is connected correctly, you should proceed to determining the presence of a so-called self-propelled device. This word denotes one of the malfunctions in which the device records non-existent electricity. Before checking the accuracy of the electric meter readings, you need to eliminate spontaneous movements of the disk, if any. To do this, you need to turn off all electrical appliances. It is important to remember that you need to turn it off, and not put it in standby mode.
A more correct result will be achieved by turning off the group machines that are located after the counter. However, they are not always present. It is also worth leaving the introductory machine in operation. Under these conditions, the counter indicator (if electronic) should not make more than 1 flash in 5–10 minutes of inactivity, and the induction device disk should not make more than one revolution. The longer this period of time, the better, but it is better to familiarize yourself with the documents supplied with the device, in which this time is indicated precisely.
Error
Next, the reading error is measured. To check the accuracy of the meter, you should use an incandescent lamp and a multimeter. It would be optimal to use the electronic version of the multimeter and not use household appliances as a load. The bottom line is that modern models of household appliances are capable of independently regulating power and therefore, given the use of their nameplate power in measurements, it will not be possible to reliably check the electric meter.
The “control measurement” process looks like this:
- mains voltage measurement;
- lamp current measurement;
- determination of the actual current strength in the lamp;
- measuring the time during which the disk of a meter connected to the network will spin 10 times while simultaneously monitoring the voltage in the network. For electronic models – 10 blinks of the indicator;
- determination of the counter constant, which is usually indicated on the front panel. For example, 3200 pulses/kWh;
- calculation of actual electricity consumption;
- calculation of the current consumed during the test;
- checking the meter for error using the formula 1000 * number of revolutions / meter constant;
- determination of the error value. Permissible error value – up to 10%
Magnetization
If one day the consumer decides to stop the device on which an antimagnetic seal is installed, you should pay attention to the sticker or indicator, which changes color in the presence of magnetization. If inspection authorities notice this, the consumer may face problems.
A counter of a simpler design can be checked as follows. You should take a thin needle and bring it to the panel - if it is attracted, this will indicate the magnetization of the counter. Usually 2-3 days after removing the magnet, this phenomenon disappears. If the magnetization does not go away on its own, you need to use a demagnetizer.
The relevance of independently checking the electric meter is due to the fact that the electricity meter may fail at some point. As a result, you will constantly overpay when paying monthly utility bills. To ensure that the meter is working correctly, you can easily check it at home without calling an electrician or removing the device from its installation site. Next, we will tell you how to check the electric meter at home for self-propelling, correct connection, error and magnetization!
How often should I check?
So, if you are familiar with one of the following situations, you need to waste no time checking whether the electric meter in a private house or apartment is winding correctly:
- Electricity consumption has increased sharply, although you use household appliances in the same mode as before. In addition, new electrical appliances were not purchased and, accordingly, connected to the network.
- The opposite situation - you began to use household appliances less often, but electricity consumption did not decrease (for example, during your long absence).
- Electricity consumption is very high, an order of magnitude higher than it could actually be. For example, if in your apartment there is nothing more powerful than a kettle, and the electricity consumption is the same as that of a neighbor who uses an air conditioner or oil heater every day.
If you are familiar with the situations listed above, read the tips below and immediately proceed to checking the electric meter for self-propelled movement and metering error. To test the device, you will need a stopwatch, calculator, multimeter and a 100-watt incandescent lamp.
Step 1 – Checking the correct connection
First of all, you must check whether the electric meter is correctly connected to the 220 or 380 Volt network. We have already described it to you. It looks like this:
If in your case the connection does not correspond to the example, you need to solve this problem as quickly as possible. Illegal connection entails not only possible incorrect operation of the electricity meter, but also the imposition of high fines.
Video review of the correct connection of the meter
Are all wires connected as needed? Let's move on to a more serious test of the device - self-propelled.
Step 2 – Make sure that the disk does not spin randomly
To check the electric meter at home for self-propelling, it is enough to turn off all the automatic switches that are located below the meter and serve the sockets, lighting group and individual electrical appliances in the house. Are there no separate machines? We simply unplug all household appliances from the outlet and set the light switches to “off” mode. In theory, in such a situation you should not have any energy consumption. We wait 10-15 minutes and perform a visual check - see whether the lamp on the front panel is blinking, or whether the disk on the counting mechanism is spinning.
If the electric meter is working properly, there should be no blinking (at most it can blink once every 5-10 minutes), and the disk should stop (or make one revolution within 10 minutes). Otherwise, your electricity meter has not passed the self-propelling pulse test and you need to call a service organization that can more thoroughly check the electricity meter in the laboratory.
Step 3 – Calculate the measurement error
To check the correct operation of an electric meter, you need to calculate its metering error. To do this, you will need a regular incandescent lamp (as a load), a multimeter, a calculator and a stopwatch. We immediately recommend reading about it if you don’t know this. You must use an electronic model (not a pointer device or a current clamp).
As for the load, it is best to use a light bulb. The fact is that modern household appliances can independently control their power (increase/lower in different modes). As a result, you will be guided by the nameplate power and use it in calculations, although in fact it will be a different value. Even if an error appears at this stage, checking the electric meter at home will not work as needed.
So, the technology for checking whether the readings are correct is as follows:
![](https://i0.wp.com/samelectrik.ru/wp-content/uploads/2015/06/proverka_schetchika-1.jpg)
Video instructions for the calculation and measurement part:
How to calculate the power of a lamp using a meter yourself?
This is how you can check the electric meter for serviceability with a multimeter at home. As you can see, the technology is quite simple and even a schoolchild can cope with the calculations, not to mention a self-taught home craftsman.
Step 4 – Checking magnetization
Very often, Internet users ask how to check the Energomera, Mercury or Neva electric meter for magnetization. The fact is that if you decide to stop the electricity meter with a magnet, and your model of electronic device has an anti-magnetic seal installed, then the check is very simple - the sticker or a special indicator changes its color. As a result, when the audit comes, you can easily be accused of illegal actions.
Once a month, each family pays for electricity costs, and the payment for 1 kW*hour only changes upward. Even with this condition, the payment is sometimes too high compared to the actual energy consumed. Then the correct operation of the electric meter comes into question. Is it possible to find out whether he is giving reliable testimony? Yes, and below we will look at ways to check the electric meter at home.
You can check the operation of the electric meter at any time. But there are cases when this is necessary:
- Energy consumption has increased sharply. But you did not purchase new electrical appliances, and the same number of people live in the apartment. Pay attention to seasonal features: in summer you can use the air conditioner for a long time, and in winter you can use the heater (they can increase energy costs);
- Ras the speed did not decrease during your long absence(went on vacation for 3-4 weeks) or decreased slightly;
- You have not many powerful household appliances, which could waste so much energy.
Attention! If you do the check yourself at home, it will not have legal force. It can only show whether the counter is overinflating. And if the check shows that this is the case, then an official verification will be required at a special institution, which will give an opinion on the accuracy of the readings of the counting device.
Checking that the meter is connected correctly
Before checking the accuracy of the electricity meter readings, you need to find out whether it is connected correctly. City apartments are powered by a single-phase network, so below we attach the correct way to connect a single-phase meter.
Four terminals are used for connection, designated 1, 2, 3 and 4, respectively. It will be correct if the phase wire goes from the power line to the meter through terminal 1, and through terminal 2 goes towards the apartment. And it will be correct if the neutral wire from the power line enters through terminal 3, and exits towards the apartment through terminal 4.
If you live in a private house, then there is a possibility that the meter is three-phase. The correct connection diagram is below.
The circuit changes only in the number of wires and terminals. The principle is the same: phase “1” should enter terminal 1 from the power line, and exit to the house from terminal 2. Phase “2” - from terminal 3 to 4. Phase “3” - from terminal 5 to 6, and the neutral wire - from 7 to 8.
Self-propelled test
Self-propelling means increasing the meter readings, even if you are not currently using electricity. To identify this problem:
- Disconnect all current consumers by pulling out the plugs;
- Turn off group machines if they are located after the counting device;
- Leave only the introductory machine turned on.
If you have an induction meter, then make sure that the number of revolutions does not exceed 6-12 times per hour: the less, the better. If you have an electronic energy meter, then you need to count the number of indicator flashes. If it lights up more than 12 times per hour, then checking is no longer required: you have already found the reason for the cheating. Otherwise, use the verification methods described below.
Pincer check
The method is good because of its measurement accuracy, but it is bad because current clamp meters are a professional tool. It’s expensive to buy just for one check, and it’s difficult to get it for a while.
The current that powers the appliances in the apartment does work. To find out whether an electric meter accurately counts energy, you need to compare two works: real (which is actually performed) and calculated (which is shown by the counting device). All measurements are compared in watt hours.
Calculation of actual work
For a single-phase meter:
- With electrical appliances running, measure the current on the phase wire coming from the second terminal;
- Additionally measure the voltage;
- Multiply the current by the voltage. Let's get the power in watts;
- Use a stopwatch to record the time during which 10 flashes occur on an electronic counter or 10 revolutions on an induction counter;
- Multiply the power by this time in seconds to get the work measurement in Joules;
- Divide the resulting value by 3600. And get the actual power consumption in Wh.
Example. Phase measurements: 20A and 220V, then the power is 4400 W. 10 revolutions were completed in 20 seconds. Then the work is 88,000 Joules. In Wh it is 24.
The formula works here: A1=UIt/3600.
Where U– measured voltage in volts, I– measured current in amperes, t– time of 10 revolutions (flashes) in seconds. A1– the required real work in W*h.
Attention! If the meter is three-phase, then you need to take measurements on each phase, then calculate the power from them. And then - the total power. Example: phase 1 – 5A and 220V, phase 2 – 9A and 210V, phase 3 – 10A and 230V. Then for phase 1 we get 1100 W, 2 – 1890 W, 3 – 2300 W. Total – 5290 W. After this, follow steps 4-6.
Definition of calculation work
Let's start with a description of the gear ratio. It is designated on each meter by the letters r or A and shows how many revolutions or pulses are made each time you consume 1 kWh of energy. There is no need for special measurements here. Immediately the formula: A2=1000n/r.
A2- this is a calculation work, n– the number of revolutions, the time of which was measured when determining the actual work. r– gear ratio (see on the meter).
Example: The gear ratio is 1400. A2=3600*10/1400. We get about 25.7 Wh. It’s the same with a three-phase meter.
Comparison of works
Formula: |A2-A1|*100/A1(answer in percentage).
Attention! The straight lines around the work difference are the modulus. It is necessary if A2 is less than A1. Then we take the modulus of a negative number, which is always positive (the minus is removed in front of the number).
Example. Let's take our values and calculate: (25.7-24)*100/24=7.08%.
Result: in our example the counter is working. If you get more than 10%, then do an official check so that the meter is changed for you.
Checking with a multimeter
The method is the same as with ticks. The advantage is the availability of the device, the disadvantage is that the reliability of the readings is lower. All actions and calculations are similar.
Testing with incandescent lamps
How to check the electric meter at home if there are no current measuring instruments? Incandescent lamps - consumers of known power - will help. You can take any number of 100 W lamps. In our example there will be 5 of them. This means the power is 500 W.
What to do:
- Turn off all devices, including the refrigerator, chargers, energy-saving lamps (they cannot be used during testing at all);
- Turn off all circuit breakers in the panel;
- Connect incandescent lamps (we have 5);
- Time it t, during which 10 revolutions of the induction counter or 10 flashes of the pulse counter are completed (we have 20 seconds);
- Calculate time T one full revolution or interval between flashes. For this t divide by 10 (it turns out 2 seconds). It would be possible to immediately calculate the time for one revolution, but then it would be inaccurate. The more revolutions you counted, the more accurate the calculation;
- Look at the gear ratio on the meter (indicated A or r, we have 3200);
- Convert the lamp power from watts to kilowatts (0.5 kW).
Then apply the formula to calculate the measurement error of the meter E:
E=(PTr/3600 – 1)*100(in percent).
Example: (0.5*2*3200/3600 – 1)*100=11.11%
Bottom line: there are doubts that the meter is working correctly, since the maximum permissible error threshold of 10% has been exceeded. A legally binding verification is required.
Electricity theft check
If the check shows that the meter calculates the energy expended correctly, but it still charges much more than your electrical appliances at home can consume, then you have a thief. One of your neighbors connected to your electrical circuit: and you pay for him at least part of the energy that he spends. In the worst case, you pay for it completely. How can you tell if your electricity is being stolen? And if so, who?
The easiest way to check
This method is only suitable for those electricity meters that definitely do not have self-propelled motors:
- Turn off the lights and all electrical appliances in the house, including the refrigerator;
- Remove all plugs from sockets (sensitive meters can “see” them);
- Go to the meter and watch for 10 minutes.
Ideally, it shouldn't spin. But 1 revolution is allowed every 5-10 minutes. If you are confident that the electric meter is working properly (there is no self-propelled one), but it still generates energy, then you have a thief. But this way you won't be able to find out who he is.
Comparison of real and measured power
This is a more accurate method of checking an electricity meter for theft. In the section on checking readings, you have already learned how to measure actual and calculated work using a multimeter and clamps. This method is similar, only you need to compare not work, but power: real power (measured in a phase) and the power of all electrical appliances currently working.
- In the whole house, only the following work: a washing machine (in the kitchen) 2 kW, a refrigerator (in the kitchen) 0.3 kW and 7 incandescent lamps (living rooms) of 100 W are on (translated into kW this is 0.1);
- The total power is: 2+0.3+0.1*7=3 kW. This is the power needed to power your appliances;
- Measure the current and voltage in the phase, multiply them by each other and divide by a thousand. If the measurements showed 20A and 220V. Their product is 4400. And if divided by 1000, then 4.4 kW.
Now compare the total power of the devices and the actual power consumed: 4.4-3 = 1.2 kW someone spends for you, and you pay. To determine who might be stealing energy, look at pass-through and hidden outlets that neighbors might connect through.
Thief identification check
If you have already realized that electricity is being stolen, you need to catch the thief. To do this:
- On the site, unscrew the plugs in your panel (you will not have electricity in the apartment, at the same time, the thief’s devices, which are powered by you, will stop receiving power);
Electricity meters installed in apartments require periodic verification.
A procedure such as checking an electricity meter is a competent confirmation that the device is in working order and suitable for further use.
It is carried out by comparing the readings of a specific electricity meter with an established reference one. The mandatory use of exclusively verified meters is indicated in the following Federal Laws of Russia:
- Federal Law No. 261 “On energy saving and increasing energy efficiency and on introducing amendments to certain legislative acts of the Russian Federation”;
- Federal Law of the Russian Federation No. 102 “On ensuring uniform measurements”.
When is it necessary to verify electricity meters?
Decree of the Government of the Russian Federation No. 250 of April 20, 2010. Electricity meters were included in the list of measuring instruments and means that are subject to regular verification. Such verifications are divided into primary and periodic:
- primary verification is carried out at the manufacturer after its assembly and commissioning;
- Periodic verification is carried out during the operation of the electric meter after the end of the inter-verification period established for the device.
There are cases when extraordinary verification is required, namely:
- if the consumer has lost the certificate of verification of the device;
- if the electric meter is being adjusted or adjusted;
- when replacing an old meter with a new device.
Frequency of meter verification
Each electric meter has a passport, which indicates the date of the initial verification. Thus, the date of purchase or installation of the metering device is not particularly important.
The inter-verification interval is counted precisely from the day of confirmation of the accuracy of the device’s measurements at the manufacturer (primary verification). As a rule, the verification period is indicated in the product passport and ranges from 6 to 16 years for different brands.
The service life of electricity metering devices is regulated by law, during which its readings are considered reliable. It amounts to:
- for a mechanical induction device with a disk – 8 years;
- for electronic devices (verification period for electricity meters depending on the specific model of the device) – up to 16 years.
In accordance with the law, the frequency of verification of electricity meters cannot exceed the above periods.
To verify metering devices, there is a specialized metrological institution that is accredited to carry out this type of activity. In this case we are talking about the Center for Standardization of Metrology (CSM).
Verification of the electric meter is the responsibility of its owner, who is obliged to independently deliver the device to the nearest standardization center (the delivery date is agreed upon in advance). It should be noted that the owner himself can initiate verification earlier than the period established by the regulations if the accuracy of the meter readings raises his doubts.
Energosbyt notifies the owner about the deadline for mandatory verification by sending relevant notifications to consumers. Metrological verification of electricity meters is a paid procedure and is carried out at the expense of the owner of the metering device.
Verification stages:
- The consumer who has received a notification from Energosbyt independently removes the electricity meter and delivers it to the CSM;
- After the verification, the certificate of its implementation is submitted to the territorial subscriber point of Energosbyt;
- Energosbyt confirms permission to use the metering device, after which it is entered into the calculation scheme;
- If the device does not comply with the required standards, then it is necessary to replace such a device with a new one.
Separately, it should be noted that an electricity meter that has a permissible percentage measurement error of 2.5 (accuracy class) may not be accepted for verification. According to GOST 6570-96 (“Inductive active and reactive energy meters”), metering devices that have an accuracy class of 2.5 are limited exclusively to the first calibration interval. Starting from 10/01/2010 Re-verification of such electricity meters is not carried out, and such devices must be replaced without fail.
It should be noted that the owner of the meter can independently choose the organization in which to verify the meter. You can often encounter the fact that an electricity supplier imposes its verifiers on consumers. In this case, be careful.
How to properly remove the meter for verification and document it
After the verification, the owner receives a verification report, which contains the final conclusions. However, you will need to properly document the process of removing the meter.
Please note that all meters at the time of installation are sealed not only by the organization performing the verification, but also by the supplier company.
Independent damage to the seal (breakage) can be interpreted as an act of fraud in order to change the readings of the meter. Such actions are fraught with an administrative fine for the consumer.
In order for the removal of the meter to be legal, a representative of the energy supply company should be invited to carry it out, whose responsibilities include:
- recording current readings;
- activating the process of removing the metering device;
- transfer of payment for electricity according to the average indicator (for the period of verification).
Reinstallation of the electricity meter must also be carried out by an employee of the electricity supply company. After this, an installation certificate for the meter must be drawn up and the meter must be sealed (the seal is attached to the cover of the terminal block).
Checking electricity meters at home
It is possible to check the electric meter at home (without removing it).
To do this, a CSM employee is called to the house, where he carries out verification by measuring the voltage in the electrical network and connecting a certain load to the network for a specific time. Based on the results of the measurements, the error in the readings of this metering device is determined, about which a report is drawn up.
Cost of the procedure
According to the provisions of clause 145 of the Decree of the Government of the Russian Federation No. 442 of 05/04/2012. all costs associated with ensuring the use of the electric meter, as well as its safety and integrity, are borne by the owner of the metering device. Thus, the cost of checking the meter must be paid by its owner. The price for such services may vary and depend on the company chosen. As a guide, we present the prices for the services of one of the laboratories in Moscow.
How much does it cost to check an electricity meter at home?
Meter verification price:
- 1-phase induction – 283.20 rubles;
- 1-phase electronic – 531.00 rub.;
- 3-phase induction – 472.00 rub.;
- 3-phase electronic - 690.30 rubles;
At the same time, due to the urgency of the verification, the price of services may be increased, namely:
- Urgent verification (1 business day) – this is + 100% of the cost of verification;
- Urgent verification (3 working days) – this is +50% to the cost of verification;
- Urgent verification (5 working days) – this is +25% to the cost of verification.
Checking the meter without removing it at home will cost the consumer more, since it will be necessary to pay not only for calling an employee to the house, but also for his urgent work. It should be noted that the consumer will spend significantly less time and effort on performing verification without removing the meter.
Please note that the electric meter is the property of the owner of the residential premises where it is installed. It is necessary to keep the passport of the metering device, as well as all documents confirming the passage of periodic verifications.
If such documents are missing, the management company may consider the device unsuitable for further use and require re-verification or replacement of the device with a new one.