What is the frequency of electricity?

What is the frequency of electricity? The following describes the basics of frequency, regionality, and measurement methods

Since electricity and voltage are invisible things, many people would think that they are elusive things. But in fact, they are only invisible, and it is not difficult to understand them. In the following, we will introduce the frequency basis of electricity and voltage, regional frequency differences, and how to measure frequency in an easy-to-understand manner.

▪ Frequency is the number of electrical waves per second

Frequency is the number of times positive and negative alternate in a second in alternating current. It is unique to alternating current, where positive and negative are exchanged regularly, and does not occur in direct current. The unit of frequency is "Hz (hertz)". For example, if there are 60 positive and negative changes per second, the frequency is expressed as 60 Hz.

In addition, an alternating current starts at 0, and the voltage changes from positive to negative and back to 0 as a cycle, with the frequency being the reciprocal of the cycle. "High frequency" refers to a high number of waves per second and a short period, while "low frequency" refers to a low number of waves and a long period.

▪ Frequency varies by country

For example, 50Hz in China, the UK and Germany, and 60Hz in the US and South Korea. There are geographical differences in frequency, but basically the adoption of one frequency for each country is mainstream.

As a special example, Japan is divided into East Japan and West Japan, with East Japan being 50Hz and West Japan being 60Hz. It is very rare in the world for a country to use different frequencies.

In the past in Japan, if you moved from East Japan to West Japan, you needed to check whether your existing appliances could continue to be used. In other words, it may be necessary to replace most of the appliances when moving.

In recent years, however, many appliances are compatible with both 50Hz and 60Hz frequencies. More and more appliances have built-in inverters that can be adapted to the frequency of the motor, thus reducing the risk of poor performance and malfunction when used in areas with different frequencies.

■ Measurement methods for frequency

To measure frequency, you can use a digital multimeter equipped with a frequency measurement function (frequency counter). In addition to expensive digital multimeters, some multimeters have this function.

Its use is very simple. The digital multimeter will be switched to the frequency measurement (Hz) function, and then the red and black pens were inserted into the positive (+) and negative (-) terminals of the multimeter, so that the measurement of the test bar contact the two ends of the circuit under test, the frequency of the corresponding part of the LCD can be displayed on the screen.

When measuring, do not forget to switch the function to frequency measurement before the test meter stick touches the measurement section. Switching the function while the test meter stick is touching may cause the digital multimeter to malfunction.

▪ Summary

Frequency is the number of electrical waves generated in one second. In countries around the world, frequencies are specified as either 50 Hz or 60 Hz. As a special case, in Japan, the frequency of electricity is divided into 50 Hz and 60 Hz, depending on the region. Recently, more and more electrical products or appliances equipped with inverters are able to support both frequencies.

There are many more cases of frequency measurements than the above mentioned IF measurements.

If you need to make your own measurements, we recommend trying the frequency measurement function of a digital multimeter.