Many people are unsure about the energy input pattern which is also called the energy meter. Understand what is an energy meter, what is the application of this important component in electrical installation and what is kWh, come on guys!

## Energy meter: What is it?

The electricity meter is also popularly known as the light clock. Its function is precisely to measure the consumption of alternating current electricity. Energy meters measure electricity consumption monthly in kWh, which we will explain what is still in this article.

Historically speaking, in 1889 the first-kilowatt-hour meter of alternating current by induction was presented to the public by Hungarian Ottó Bláthy. He showed the energy meter at the Frankfurt Fair and the success was so great that in the same year it was already being sold.

## Energy meter: What types?

Currently in Brazil, the most used electricity meter is the biphasic 3-wire meter. Know that there are two types of electricity meters, electronic and electromechanical.

## Electromechanical energy meter

The electromechanical type meter is older and works through electromagnetic induction. This type of meter has a metal disk that rotates when electricity passes through the coils, generating a magnetic field. This field will only propel the disc by rotating it when energy is being consumed. And in these conditions, the movement of the gear and the hands of the meter happens.

The speed of rotation of the disk is directly related to the magnetic field. Therefore, the stronger the magnetic field, the faster the disk will rotate and, consequently, more energy will be consumed.

As was said, the electromechanical energy meter is the oldest type, yet it remains very efficient and for this reason, it remains widely used in several countries around the world.

## Electronic Electricity Meter

As its name suggests, the electronic energy meter works electronically, that is, its measurement is performed digitally. The technology used in electronic meters is much more modern.

This type of meter has a device that sends information about energy consumption directly to the utility. So, there is no need to send an employee to read the meter.

## What is kWh?

kWh means Kilowatt-hours and is basically the measure of the electrical energy consumed by an appliance in a given period. Therefore, one Watt-hour represents the amount of energy needed to power equipment that has a power of 1 Watt for one hour.

Thus, a device with a power of 5400 W indicates that this is its power for a period of 1 hour. So, if this device stays on for 5 hours the energetic consumption will be as follows:

- Consumption = Power x Time of use
- Consumption = 5400 W x 5 h
- Consumption = 27,000 Wh or 27 kWh

You must understand that there is a big difference between kW and kWh! KW is a measure of power, while kWh is a measure of energy. To obtain the value in kWh, it is necessary to divide the result by 1,000, since 1 kWh is equivalent to 1,000 Wh).

Therefore, the greater the power of a device, the greater its energy consumption. Knowing this difference, we can explain the monthly energy consumption in an electricity bill.

Let’s use for example an invoice in which consumption was 108 kWh / month. Analyzing that in a month we have approximately 720 hours, the calculation is as follows:

- Energy = Power x Time
- 108 kWh = Power x 720 h
- 108 kWh / 720 h = Power
- Power = 0.15 kW or 150 W

In this video below the Mundo da Elétrica channel, you can check very important information about the entry standards, it’s worth checking out!

By carefully observing all the information and examples that have been passed, it is easy to understand the application of energy meters! However, before choosing the entry standard for your property, it is necessary to consult the rules and requirements of the dealerships. Never make installations outside the norms or make inappropriate changes to the installations and / or the meters, because the power cat is a crime and can bring serious complications.

If you have any questions or suggestions, leave them in the comments and we will respond. Who knows your question may not become a topic of an upcoming article for the World of Electrical!