How to check the correctness of the readings of the electricity meter

Checking the readings of the electricity meter

The measurement of electricity consumed by all devices and lamps in the apartment is carried out by electricity meters. According to their readings on the electricity meter, the payment for the use of electricity is calculated.
If you doubt correct meter readings, it can be checked easily.

For this you need, first disconnect from the network all lamps, devices, radio stations available in the apartment and make sure that the counter visible in the viewing window does not rotate. If the disk continues to spin, it means that somewhere the drive is not turned off.
It must be turned off, otherwise the meter cannot be checked.

The counters are different. Some of them report electricity consumption in kilowatt-hours (kWh), others in hectowatt-hours (hw-h). On the dashboard of each meter, the number of disk revolutions corresponds to the consumption of one kilowatt hour and one hectowatt hour of electricity.

For example, on the panel of the meter it can be written: "1 GW-h = 300 revolutions of the disk" or "I kW-h = 5000 revolutions of the disk".

To check the glucometer, you need to know how much energy corresponds to one revolution of the disc. This value is denoted Csch. Obviously, if the counter says. 1 kWh = 5,000 revolutions of the disc, then his

Cw = 1/5000 kWh.

If the meter shows that 1 GWh = 300 revolutions of the disk, then this meter has

Ssch = 1 / 300 gwh.

When checking such a counter, the value
Mt. must be expressed in kilowatt hours. Since 1 kWh = 10 GWh, then Cm = 1: 3000 kWh. Once you know all these data, you can start checking the meter.

It is best to use light bulbs for testing. You need to turn on one or two lamps with a total power of 75-100 watts (W) and for 5 minutes (5 : 0.6- hours) calculate the number of revolutions of the disk according to the red light.

The energy consumption of the lamps is determined by the formula A1= 5 : 60 x R

where A1—Real electricity consumption in kilowatt hours; R — the power of the included lamps in kilowatts (kW).

Usually the wattage of lamps is indicated on their caps in watts, so it should be converted to kilowatts, based on the fact that 1 kW = 1000 watts

For example, 75 watts = 0.075kw, 25w = 0.025 kW.

The energy consumption shown by the meter is determined as follows:

A2 = Cschx H.

where2,— electricity consumption in kilowatt hours; Ssch — electricity consumption in kilowatt hours for one revolution
counter disc;

n — the number of disk revolutions in 5 minutes.

If1 = A2, then the counter is working correctly. However, for household measuring devices, an error of no more than 4% is permissible.If the difference between the calculated values ​​A1 and A2
more than 4%, then the meter readings can be considered incorrect.

An example.

The network includes two lamps with a power of 55 and 75 watts. The counter was made during the control measurement 60 revolutions in 5 minutes. The device shows that 1 GWh = 558 revolutions of the disk, i.e. Cs = 1 : 558 hw-h, or 1 : 5580 kWh Determine the actual consumption of consumed electricity
burning lamps.

The power of the lamps is equal to: 55 W + 75 W = 130w = 0.13kw. During 5 minutes these two lamps must consume electricity:

A1= 5 : 60 x 0.13 = 0.01 kWh.

Energy consumption displayed simultaneously by the meter.

A2 = 1 : 5800 x 60= 0.01 kWh
A1 = A2.

Therefore, the counter is displayed correctly. Installation of a control counter. To account for electricity consumption in just one meter is installed for each apartment located under the control of Energosbyt. However, in cases where several residents live in an apartment and each of them uses different household electrical appliances, the calculation of electricity use sometimes causes difficulties. That is why many residents install so-called control meters in their rooms. Such meters are not controlled by Energosbyt organizations, but are used to record the electricity consumed by individual residents and ensure the correct settlement between them.

Control meters are sold commercially both separately and panel-mounted together with plug-in fuses. Meters are designed for a certain voltage (127 or 220 V) and for a certain electric current (5 or 10 A).If you have household electrical appliances, you should buy a meter for 10 A and for the voltage that is available in the apartment.