Checking the voltage in the 220V electrical network using a multimeter

Various types of measuring instruments are used to determine if there is voltage in the power grid. For example, you can check the voltage in the outlet with a multimeter, since such a device is as functional as possible. Safe and fast work is done quickly and easily.

Socket voltage

The household network gives indicators in the range of 198-242 V. Such a run-up is optimal for most electrical appliances. But if the voltage in a thunderstorm, for example, rises to 270 V and above, the equipment and household appliances will simply burn out.

Only alternating current flows in the outlets. It is worth remembering this when working with a multimeter.

What is the voltage measured for?

The centralized power supply is provided by a separate winding of the three-phase transformer. A certain number of consumers (houses, apartments) are simultaneously connected to it. Their total number is divided into groups. Each of the castes is connected to one of the three phases (windings) of the transformer. Moreover, its capabilities (power) are limited. If the total load in all apartments exceeds the permissible value, the voltage in the electrical network drops to 198 V and below. In this case, the work of household appliances will be incorrect.

Measurement of indicators by Volts is carried out in order to ensure the normal operation of electrical appliances in the house. Or to determine the possible causes of equipment malfunctions.

How can you take measurements

Before you measure the voltage in the outlet, it is important to know that for these purposes you can use:

• a voltmeter familiar from school (rare in everyday life);
• a multimeter familiar to many masters (multifunctional device);
• tester, he is a multimeter, but a pointer.

You can also check the presence of mains power with an indicator screwdriver. But it does not show the voltage value, but only determines its presence or absence by backlighting.

Measurement with a multimeter

Before you check the voltage in the 220V network with a multimeter, it is advisable to understand the device and the marking of the device. Better to use a digital mechanism. He correctly displays information, is loyal to the wrong connection of the probes. Additionally, digital measuring devices are unpretentious in operation.

The main components of a multimeter:

• LCD screen for displaying indicators.
• A wheel used to set the modes (parameters) of the device.
• Probes (2 pcs.) - red and black. Measurements are carried out directly with their help.

In turn, the control wheel has a circular scale with markings for various test parameters. Their designations are interpreted as follows:

• V = - determination of DC voltage;
• V ~ - AC voltage;
• Ω - allows you to recognize the resistance;
• A = - definition of direct current;
• -hFE - check the operability of the transistor;
• o))) - fast continuity of the electrical circuit;
• OFF / ON - off / on.

Nominal measurement ranges are provided for each of the parameters. They are indicated on the panel of the multimeter.

Often, the constant "=" and alternating "~" currents can be replaced by the abbreviations DC or AC. For example, to set the control wheel to the parameter for measuring AC voltage, you need to turn it to the abbreviation ACV or VAC.

Preparatory stage

Additionally, before you measure the voltage with a multimeter in the outlet, it is worth finding out the purpose of all its connectors on the case.

• 10ADC. It is intended only for determining the parameters of the DC current. The maximum allowed value is up to 10 A. Only the red probe is always inserted into this connector.
• COM. The connector is shared. Only a black probe is always connected to it for measurements.
• VΩmA. A connector that is designed to perform all basic measurements such as amperage (up to 10 A), voltage or resistance.

The VΩmA connector is used more often.

Connecting a multimeter and taking measurements

To perform work, you need to correctly connect the probes. The red one is inserted into the VΩmA connector, and the black one into the COM. Next, you need to switch the control wheel to the desired operating mode of the device. To determine the voltage, it is set to the abbreviation ACV or V ~. In this case, the position of the wheel must be set so that it is at a mark above the estimated mains voltage. For a household power point, the indicator is 220 V. So you need to set the nearest higher value. For most multimeters, this will be 750 V.

If the master does not know the estimated voltage and it turns out to be higher than 750 V, this threatens an accident. In the best case, the device fuse will blow. In the worst case, burns to the hands of the master are possible. Therefore, before taking measurements, you should find out the characteristic Volt indicator for the network.

Inserting the test leads into the socket

When installing the probes into a power point, it does not matter which of them to insert into which socket of the socket. The main thing is to strictly hold the wires for the insulation, and not for the bare parts. It is important to make sure that the probes do not touch each other. Otherwise, a short circuit will occur.

If the connection of the wires is done correctly, the display of the device will reflect the current state of affairs. The digital voltage value will be displayed. It will never be equal to 220 V. An error of +/- 20 is considered normal. Therefore, if an indicator of 235-238 Volts is displayed on the screen, you should not be alarmed. According to GOST, voltage deviations of 10% are permissible.

Safety engineering

The multimeter is a portable multifunctional measuring instrument. It is powered by a battery. The device is safe for the master, subject to safety precautions:

• If the master does not know the pre-voltage in the network, it is possible to measure the indicators, but the control wheel must be set to the highest Volt indicator.
• It is advisable to work in dielectric gloves (you can use ordinary household, rubber).
• When determining the resistance of the network, it is advisable to make sure that the power is completely turned off, and the capacitors are brought to 0 (discharged).
• During operation with a 20 A power point, measurements are taken no more than 15 seconds.
• Do not check the network performance with a multimeter in a high humidity environment.
• It is forbidden to turn the control wheel and set it to other modes during measurements.
• Do not use the device if the sheath of the probes is damaged, the case is visibly damaged.
• Replace the battery of the device only after setting the impeller to ON mode and disconnecting all probes / wires. The spent element is disposed of in special waste. Do not dispose of batteries or accumulators with household waste. This leads to environmental pollution.

Subject to all operating principles and safety precautions, measuring the voltage in the outlet takes no more than one minute.