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 proper 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 themselves or whether they 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 tariffs.
When should the test be performed?
For various reasons, the owners of a house or apartment may have doubts about whether the electric meter is working correctly. In this case, you need to find out how to check it. It is worth understanding that such a procedure has nothing to do with verification. It has no legal force. Such a check is necessary if the owners doubt the correctness of the electricity meter.
If some violations are identified, you need to contact a specialized organization. Its employees will confirm or deny the fact that the device is not working correctly.
Checking whether the electric meter is counting correctly is quite simple. This is a simple process that almost anyone can handle. But in some situations it is necessary to perform a check. These include the following.
- For unknown reasons, the amount of energy consumed has increased. At the same time, the owners no longer began to use electrical household appliances and did not purchase new equipment. Electricity consumption may increase if you purchase a washing machine, air conditioner, heater, multicooker, etc. Also, the number of kilowatts consumed per month may increase if more people begin to live in an apartment or their own house. In some cases, changes in this indicator may be due to seasonal changes. If there were no such facts, but the electricity consumption indicator has increased noticeably, you need to check.
- The meter readings have not decreased compared to last month, although the owners were not at home for a long time (at least a week). It should also be alarming if the indicator has decreased disproportionately.
- Electricity consumption, according to the meter, clearly exceeds the available capabilities of household appliances.
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, please use the verification methods described below.
Preparing for the test
Before checking the correct operation of the electric meter, you need to perform some preparatory steps. It is necessary to exclude the possibility of “self-propelled” occurrence. This term is used to describe a situation when all electrical appliances in the home are turned off, but the meter still works, the disk generates kilowatts.
You need to leave the meter energized, but you will need to turn off the single-pole circuit breaker. If the system has plugs, they need to be removed. Then you need to observe the operation of the device for 15 minutes. If the system has a disk, during this time it can make only one revolution, but no more.
If you are interested in how to check the correctness of the readings of the Mercury electric meter or other popular modern models, you need to focus on the operation of the indicator light. It emits light pulses. When consumption in the home is completely turned off, it can emit only one signal.
It is also worth considering that it is not normal if the meter shows fewer kilowatts per month than usual. If the owners have not limited themselves in energy consumption, but a similar situation occurs, they need to check the integrity of the device housing. This action must be performed in accordance with all electrical safety requirements. If there are defects, the meter needs to be replaced. To do this, they call in experts from the electricity supply company. They will conduct the appropriate examination. If it turns out that the user performed some actions to save money by disrupting the operation of the device, he will pay a fine. Therefore, all steps to check equipment must be performed very carefully.
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 this procedure simply cannot be avoided. 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 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.
How to detect electricity theft?
When checking the electric meter for correct readings, it is necessary to exclude the possibility of energy theft. If all household appliances in the apartment are turned off, but the device still counts kilowatts, this may indicate that it is broken.
But sometimes, especially in an apartment building, such a situation may indicate unauthorized use of electricity by neighbors. In this case, additional wires will run from your meter into the panel. Sometimes this is difficult to determine if the person is not an electrician. Tangled twists can confuse even a professional.
Thief identification check
If you have already realized that electricity is being stolen, you need to catch the thief. For 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 no longer be powered);
- Go one floor higher, or go into the apartment and look through the peephole;
- It may take a lot of time, but sooner or later the thief will want to turn on your panel.
You will see someone come and screw in the plugs in your panel so that you can use your electricity again. Catch the thief! It is he!
These simple algorithms for checking the accuracy of your meter readings and checking for electricity theft will help you determine if you are paying too much. And if this is the case, then get an official conclusion to change the meter for free (in case of high measurement error). And when identifying a thief, it will be easier for you to prove the fact of theft.
Illegal actions on the part of the owners
Sometimes apartment owners themselves use various methods in order to reduce the speed of electricity consumption by illegal means. Outside interference in the system may damage the device. In this case, inspectors will definitely find additional devices. Illegal interference with the meter system is indicated by:
- A hole drilled in the body. It is used to use a needle to slow down the rate of counting consumed kilowatts.
- Lack of glass on the electric meter. Instead, they can insert photographic film. But such material leaves a mark. This will definitely be revealed during the examination.
- Connecting additional wiring, due to which some of the electricity is not recorded. Such a wire can be easily found using a detector. It usually hides behind plaster or baseboards.
- Loose tension screw. This can be done if there is no seal on the meter.
To avoid problems with the inspection company, you need to periodically inspect the device for damage. Checking the electric meter for proper operation necessarily begins with a visual inspection.
Checking the correct connection
How to check if the electric meter is counting correctly? It is necessary to determine whether the device is connected correctly. If there are violations, the equipment will not work properly. Therefore, you need to take appropriate actions. Most often, single-tariff (single-phase) meters are installed in apartments. This equipment is characterized by direct connection. You need to inspect how the wires are connected. If everything is in order, you need to use special equipment (clamp meters). You can buy them at a specialty store or rent them from a familiar electrician.
Using the presented equipment, you can determine what load is acting on the network. When using current clamps, there is no need to perform complex calculations. If you plan to periodically check the operation of the electric meter, it is best to purchase equipment from a specialized store. In this case, it will be possible to obtain an accurate result at the slightest need.
How to check if an electric meter is working correctly using a clamp meter? You need to read the manufacturer's instructions for the equipment presented. Next you need to switch the range to the ACA 200 position. This is the optimal mode for checking the correct connection and operation of the meter.
The pliers need to be opened and then fixed around the phase wire. They should cover just one wire. You can take measurements on an insulated wire that is brought into the apartment. The result will appear on the device screen. It is measured in amperes. This figure must be multiplied by the network voltage (220 V). The cosine must be equal to 1.
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.
Measurement error
There is another way to check whether the electric meter is counting correctly. After all, not everyone has special equipment at home in the form of current clamps. One of the methods for checking a calculating device is to determine its error. To find out, you need to prepare a simple incandescent lamp that will create a load. In addition, you need to prepare a calculator and a stopwatch. Measurements will be carried out using a multimeter. It must have an electronic display. A dial multimeter is not suitable for this.
The use of a conventional lamp during the examination allows one to obtain an accurate result. If you use household appliances for these purposes, you may get the wrong result. The data sheet indicates the maximum power of the device. But many of them consume different amounts of electricity in different operating modes. Because of this feature, it will not be possible to accurately determine the meter error. An ordinary incandescent lamp works stably. Therefore, it is used during testing.
When considering how to check whether the electric meter is working correctly, you need to familiarize yourself in detail with the presented methodology.
First, use a multimeter to measure the voltage in the network. How to perform such an action should be read in the manufacturer's instructions. The result will almost never be exactly 220 V. For example, it may turn out to be 223 V or some other value. It is written down on a piece of paper.
Next, the lamp current is measured. For this purpose, the tester is switched to ammeter mode. It is connected to a light bulb. The resulting value, for example, can be 0.43 A. To find out what power the light bulb will have at this network voltage, you need to perform a simple calculation:
223 × 0.43 = 96 W
This deviation is 4%, so standard values cannot be used for calculations. They may differ significantly from actual figures.
How to calculate deviations in measurements at home
If the meter is working properly, but the bills are too high, perhaps someone is stealing the energy.
To avoid resorting to the services of specialists, you can use several simple and affordable ways to check the electric meter using inexpensive tools and devices.
Checking with a tester
The method of examining a meter with a tester is completely similar to working with a current clamp. The difference lies in the accuracy of the results obtained. To reduce measurement error to a minimum, you should spend 10 times more time on measurements, introducing this coefficient into all preliminary and final calculations.
Incandescent lamps
You can find out the accuracy of the meter readings using a 100 W incandescent lamp. A prerequisite for testing is to disconnect all consumers. The readings are recorded, after which the lamp is connected to the network for 1 hour. Upon completion, new readings are taken. They should increase by 100 W with a permissible error of 10%.
Features of checking a three-phase meter
On three-phase meters, measurements are taken alternately on all phases. After this, the power for each is calculated, the sum of the indicators gives the final result of the real and demonstrated power.
Electricity theft is not uncommon. A person who understands electricity and has access to the switchboard can connect to someone else’s line. You should start by monitoring the device with consumers disconnected throughout the apartment. If, in the absence of self-propulsion, the device shows a load, energy is being stolen. You can inspect the shield yourself, but it is better to do this in the presence of representatives of the resource supply organization.
Subsequent calculation
When considering how to check an electric meter for correct readings, you need to delve into the essence of calculating real network indicators. To do this, you will also need to calculate the lamp resistance. To do this, the network voltage is divided by the load of the electrical appliance:
223 ÷ 0.4 = 557.5 Ohm
Now you can start checking the counter. You need to connect the lamp to the network. Then, using a stopwatch, it is measured how long it will take for the counter to blink the indicator 10 times or make 10 revolutions of the disk. At this moment, it is important to control the voltage in the network. For example, during measurements it was found that the disk made ten revolutions in 2 minutes (120 seconds). The voltage during the test remained at 223 V.
Next, on the front panel you need to find the constant value of the electric meter. This, for example, could be 3,200 imp/kWh. Other values may be specified. Next you need to perform the calculation using the following formula:
PE = NS × NS ÷ SL, where
PE – lamp electricity consumption (real),
NS – network voltage,
RL – lamp resistance.
PE = 223 × 223 ÷ 557.5 = 89 W
You need to calculate how many watts the lamp consumed during the test:
120 sec × 89 W ÷ 3600 = 2.97 Wh.
To determine the error of the meter, the following calculation is performed:
1000 × number of revolutions ÷ constant value indicated on the front panel of the meter. Substituting the available values, we get:
1000 × 10 ÷ 3200 = 3.13 Wh
Error = (2.97 – 3.13) ÷ 3.13 × 100 = -5%.
This is a minor error. It is within acceptable limits. A deviation of 10% is allowed. In the example shown, the counter works correctly.
Magnetization
When considering how to check an electric meter for correct readings, you need to consider such a feature as magnetization. Some users use a magnet to reduce the speed of kilowatt counting. You should not resort to such actions. Such a trick will definitely be revealed during an audit. To understand why you should not resort to magnetizing the meter, you need to consider the features of the test.
Thus, in modern models of the presented devices, for example, “Mercury”, “Neva”, “Energomer”, etc., a special magnetic seal is installed. This is a special sticker that, if the counter stops in a similar way, will change color. If this happens, during verification the user will be accused of illegal consumption of electricity.
In simpler meter models, you can also check the serviceability. For this you need a thin metal needle. If it is attracted to the meter panel, then it is magnetized. But in such models, if you remove the magnet, the field is restored in literally 2-3 days. In some cases, magnetization does not go away. In this case, you need to buy a special demagnetizer.
Two- and three-tariff meters
It is easy to check whether a three-phase or two-phase electric meter is operating correctly. Such devices have certain operating features. At different times of the day, the cost of electricity calculated by such devices differs. At night the tariff will be slightly lower than during the day. This counting feature allows you to reduce the load on the network during the daytime.
For this reason, two- or three-phase meters are called two-tariff and three-tariff. They help reduce your energy bill. At the same time, uneven consumption leads to intense environmental pollution during the day and evening. Consumption of electricity at night is better for the environment.
The disadvantage of using such devices is the high demands placed on the correct operation of electrical appliances. Otherwise, significant savings will not be achieved.
In what cases are metering devices verified?
Induction and electronic devices have an operating life that is set by the manufacturer. For metering devices with a magnetic disk it is 8-10 years. Electricity meters: “Energomera”, “Niva”, etc. are verified every 16 years. Technical measures can be carried out earlier if there is reason to doubt that the metering device is damaged.
The timing of verification of electricity meters is indicated in the technical documents attached to the device. The initial work is carried out by the manufacturer. Based on the results of the procedure, the metrologist draws up a report on the suitability of the electric meter for use or the need for replacement (indicating its shortcomings). It must be checked at your place of residence and not necessarily at the company recommended by utility services. To install an electricity meter, you need to use the help of an electrician.
Frequency of verification according to law
There is no single set deadline for the verification period of electric meters. It must be looked at in the technical passport. Federal Law No. 102, the law on energy saving, does not prohibit the purchase of a new device during the calibration interval, without conducting metrological tests of the old one. The homeowner must focus on the technical documentation and promptly invite a specialist from the supplier company to draw up a report. The verification period for electric meters is usually at least 8 years.
Unscheduled inspection
You will need to check the electricity consumption meter if there is reason to doubt the correct operation of the electricity meter.
For this you will need:
- make sure that the wiring is connected correctly;
- invite a specialist to draw up a certificate of removal of the electric meter and send it for metrological tests. The exact verification period must be found in the device passport;
- submit payment receipts.
Unscheduled measures will be needed when documents confirming a previous inspection are lost, or when it is necessary to set up and adjust the electric meter.
The corresponding activities are carried out by inspectors who compare the readings with the information specified in the calculation databases. It is necessary to check the electric meter if the device fails.
Checking a two-tariff meter
How to check a two-tariff electric meter for correct readings? You need to follow a few simple steps. First, check that the electrical appliance is connected correctly. The device is also checked for the presence of “self-propelled”. If no problems are found in this indicator, you can proceed with further testing.
How to check the electric meter for correct readings? All electrical appliances are disconnected from the network, and all machines coming out of the panel are turned on. Next, the above procedure is carried out with a lamp and a multimeter.
