What is a electric load? (Beginners, 2024)

Have you ever wondered what happens when you plug in a device, flip a switch, or press a button? The answer lies in the concept of “loads” in electrical circuits.

The electric load in the circuit is a device that uses or consumes electrical energy. There are also different types of load. In electronics, the circuit is the logical connection of different components, and you notice the output can be to light up a bulb or turn on the motor. These are what we call loads.

In this article, we’ll learn about what is electric load and its types with various examples in detail.

What is the circuit?

Before we go into the details of the load, first we have to know what is the circuit.

A circuit is a logical connection of electrical or electronic components that solve a specific task.

A simple circuit consists of a power source typically a battery. This battery is connected to a load.

In the above circuit, there is a battery, load (lightbulb), conductor wire, and switch. So we can say the circuit has four components.

If you want to learn more about the electronic circuits, Check out the article:

Electronic circuits for beginners

Now the question is what is meant by load in circuits.

Electric load

Have you ever wondered why we make circuits by connecting different electronic components?

We design circuits to control the flow of current, enabling electronic devices to operate. Without a connected device, the current flow serves no purpose.

Now the load can be defined as,

An electrical device that consumes energy or electricity is called a load. The load converts electrical energy, current, or power produced in the circuit to another form of energy such as light, heat motion, etc.

When you turn on a light switch at home, the light illuminates, indicating that the light is consuming electricity and converting it into light energy. Equipment that uses electrical energy for work or to produce any other kind of energy is referred to as an electric load.

Electricity is produced when we connect a conducting wire to the battery but if we don’t connect a device to make use of this electricity then it is useless.

We can also say, the load is something that makes use of electricity and converts it into another form of energy.

In the above circuit, there is no load but a battery that is connected to the switch through a conducting wire. So the current produced from one terminal will flow through the switch to another terminal of the battery.

As you can see there is no useful use of this current as nothing is turning on or off.

But now we have connected the lightbulb. When the switch is turned on the current will flow from one terminal through the lightbulb to light it up to another terminal of a battery.

The lightbulb consumes current and converts the electric energy or current into light energy and acts as a load. This is how a load is important to make useful use of electric current.

Types of electric load

Three natural types of load are resistive load, inductive load, and capacitive load.

Let’s explain these different kinds of loads in detail.

1. Resistive load

Any load that has a heating element is called a resistive load. A heating element converts electrical energy into heat energy.

Some of the resistive loads are incandescent bulbs, electric heaters, electric irons, toasters, ovens, and coffee makers.

As we know the resistor opposes the flow of current in the circuit. So the resistive load blocks the flow of electrical energy in the circuit and converts it into thermal energy, due to which the energy dropout occurs in the circuit.

We can also say that a resistive load is a term for an electric load type whose operation is dependent on the resistance characteristic of the material.

In resistive load, the voltage and current are in phase with each other which means the voltage and current waveforms will start at the same, will reach their peak value at the same, and will reach zero at the same time. This all is shown in the above graph.

The power in these loads flows from source to load only so these loads only use active power.

The power of resistive load is always unity as the load takes the power in such a way that the current and voltage remain in the same phase.

Properties of resistive load

Following are some properties of resistive load.

The current and voltage of the load are always in phase.
These loads always use active power to function.
The power always flows from source to load.

2. Inductive load

When the load uses a magnetic field for doing work is called inductive load. When the current passes through a conductive wire it forms a magnetic field.

In inductive load, the voltage and current are out of phase with each other by 90 degrees.

As shown in the above graph, the voltage and current waveforms started at different times. They reach their peak value at different times and they also reach zero at different times.

In inductive load, the current lags the voltage this is because an induced electromotive force produces current. When there is no voltage there will be no current. So the power factor also lags.

In these loads, the power flows from source to load or even from load to source. They only consume reactive power.

The transformers, generators, and anything that has motors are examples of inductive loads.

These loads are not easily operable as they create lots of problems in the system. But still, they are equally important as a resistive load. Switching such loads can be challenging because the current in these types of loads lags the voltage by 90 degrees.

Properties of inductive loads

Following are the properties of inductive loads.

These loads use reactive power.
The waveforms of voltage and current in such loads are 90 degrees out of phase with one another.
The power flows from source to load and from load to source.

3. Capacitive load

The capacitive load has properties of both the capacitor and resistor. Since it is generally impossible to have only capacitive loads, all capacitive loads have both capacitive and resistive qualities.

In capacitive load, the capacitive reactance resists the change in the voltage causing the current in the circuit to lead. The current and voltage are out of phase.

The applied voltage is always 90 degrees ahead of the current. There is a leading power factor in the capacitive load.

Some examples of capacitive load are capacitor banks, buried cables, and capacitors used in various circuits such as motor starters.

Now that you have a better understanding of electrical load, continue your learning journey by exploring our comprehensive guide, Basic Electronics for Beginners, where we cover essential concepts like circuit components, Ohm’s law, and much more.”

Conclusion

Electrical loads are the workhorses that convert electrical energy into the functions and conveniences we enjoy daily.

When there is no load the current produced by voltage is of no use.

The load is an electrical device that converts the electrical energy into another form of energy. The load has various types and these are resistive load, inductive load, and capacitive load.

The resistive load is the type of load that has a heating element in it and the voltage and current are in the phase means the waveform of voltage and current starts at the same time.

The inductive load uses a magnetic field to do work. The voltage and current are not in the phase by 90 degrees means both voltage and current don’t start at the same time.

The capacitor load has a capacitor and resistor properties because the implementation of just a capacitor in the load is not possible.

This was all about the load, I hope this will help you in understanding load and its types.