What is a Single Phase Energy Metre – Its Mechanism and Application

Want to check the power consumption of your household? If yes, a single phase energy metre is what you need. 

Despite several types of energy meters available in the market, a single phase metre is ideal for calculating energy consumption by home over a specific period. 

By home, we mean it measures the energy used every day by the fans, lights, refrigerator, television, and other household appliances. 

The best feature of a single phase energy metre is that the operation is simple, unlike the three phase energy metre.

Curious to know more? Let’s have an analytical discussion on a single phase electricity metre. 

What Is a Single Phase Energy Metre? 

As discussed earlier, the sole purpose of a single phase energy metre is to measure energy consumption by a home. 

This metre requires 1-phase for distributing the load. Simply put, the metre needs only two wires to send the power – one phase wire and one neutral wire. 

This factor makes a single-phase metre less efficient than the three phase energy metre as it has less power for distributing alternating current. 

Since it supplies less power than the three phase metre, it is ideal for use at home instead of in industrial or commercial settings where more power is required. In commercial or industrial settings, a three phase metre is ideal. 

You can expect the maximum voltage required by the single phase metre to be 230V with a 50Hz frequency. 

Construction of Single Phase Energy Metre 

Now that you’re familiar with what a single phase energy metre is, let’s discuss what goes into making a single phase electricity metre and how each component ensures efficient functioning of the watt-hour metre or single phase metre. 

1. Driving System

Let’s begin with the driving system. This system contains two electromagnets – series and shunt magnet. 

The series magnet supplies the load current, whereas the shunt magnet supplies voltage. 

When the series magnet winds up, it is known as the current coil; when the stunt magnet does, it is called the pressure coil. 

The electromagnet’s core is made of silicon steel and remains laminated. You might ask why lamination is necessary. Well, it helps to reduce electrical losses that usually occur in the form of heat. 

A copper band is also attached to the shunt electromagnet’s centre limb that helps to align the magnetic flux in a perpendicular state. 

All these occur within the driving system of the single phase energy metre.  

2. Moving System

Moving on, the moving system consists of an aluminium disc pressed within the current and pressure coil. 

The load and the voltage-current produce alternate fluxes that move through this aluminium disc. 

When this happens, an electromotive force (emf) gets generated. This force allows eddy current to pass into the disc. 

3. Braking System

This is one of the most important components of the single phase energy metre. The braking system controls the aluminium disc’s rotational speed. 

Besides, when the load is disconnected, it helps to bring it to its original state. A braking magnet is situated within the disc that creates braking torques, thereby reducing the speed of the disc. 

4. Registering System

Lastly, a registering system counts the number of disc rotations. Note: The disc rotation is equal to the power consumption. The load’s consumption is measured in a kilowatt hour. 

So, these are the four components of the single phase energy metre and the role of each in ensuring effective functioning. 

Now, let us familiarise you with the benefits of this metre. 

What Are the Benefits of a Single Phase Energy Metre?

If you are planning to purchase a single phase electricity metre, know its advantages before purchasing to make an informed decision. 

  • – It is a multi-functional energy metre. In other words, you can use it for prepaid and anti-theft functions. 
  • – The metre requires low power to operate.
  • – It is lightweight and has a long shelf life.
  • – The single phase metre generates accurate results. 
  • – It comes in a compact size but provides optimal performance. 
  • – Strong load capacity is one of its important features. 
  • – The electric energy metre can calculate twelve time periods and four rates. Each period and multi-tariff rate can be adjusted if required. 
  • – The metre is equipped with a real billing function. 


The single phase energy metre is ideal for daily household use. It has a simpler network than the three phase energy metre

If you’re looking for an energy metre that can measure power in residences, considering a single phase electricity metre is the best choice. 

Should you consider buying it? Definitely, yes! You can consider buying a single phase energy metre as it is easier to use and install than the three-phase energy metre. 

Besides, it provides accurate energy readings whenever you wish to use it. Apart from this, it comes at a much cheaper rate than the third phase energy metre as fewer conductors are used in its making.  


Q. What is an energy metre?

An energy metre is a device that calculates the power consumption in residence, commercial and industrial settings and displays it on the device. 

The metre helps to keep track of energy usage at a specific time. You can use it for billing and monitoring purposes. 

Q. How can I read my single phase metre?

Reading a single phase energy metre is not complex. You’ll find a display register that shows recorded registers, metre readings, and the power consumed at different tariff rates. There’ll be a section where you’ll find the serial number of your energy metre. 

You’ll also find a pulse indicator that will indicate (on and off) during the electricity usage. 

This indicator will work rapidly if household appliances are using excessive energy. If not, you can be assured that the power usage is controlled. A scroll button will also show the next reading register display on the click.  

Q. How does a single phase energy metre operate?

The single phase energy metre works on two mechanisms: The mechanism of an aluminium disc rotating at a speed similar to the power consumption and the means of calculating and showing the power transferred.