Circuit Diagram: Definition, Components, Types, Example

Circuit Diagram is a graphical representation of an electric circuit. It is useful for determining the usage of an electric circuit in terms of designing, constructing, and maintaining of electrical and electronic devices. Circuit diagram can also be known as an elementary diagram or electronic schematic diagram. It majorly defines the simplified graphical representation of an electric circuit. 

Read Also: Resistivity Temperature Dependence

Key Terms: Circuit, Resistor, Electric Bulb, Battery, Electric Circuit, Electricity, Ammeter, Voltmeter, Electric Current, Elementary diagram, Electronic schematic diagram

---

What is a Circuit Diagram?

[Click Here for Previous Year Questions]

A circuit can be defined as a pavement that, in turn, is utilized by the electric current to travel. Therefore, a circuit diagram can be considered as a graphical demonstration of an electrical circuit.

• The electrical circuits are represented through the lines that denote the wires.
• Various other symbols are used to denote electronic & electrical constituents.
• It helps electricians in their field jobs as they are dependent upon an electric circuit diagram for initiating any wiring-related work.

A circuit diagram basically helps give a graphical representation of an electrical circuit. Circuit diagrams generally exhibit the relative positions of all the elements and their connections to each other. 

Discover about the Chapter video:

Current Electricity Detailed Video Explanation:

Also Read:

---

Circuit Diagram Explanation

[Click Here for Sample Questions]

The graphical representation of an electrical circuit, a circuit diagram is also called an electrical diagram, elementary diagram or electronic schematic. Circuit diagrams are used for the design, construction and maintenance of electrical and electronic equipment.

A simple circuit diagram contains three components that are considered vital for operating an electrical circuit:

• Voltage source
• Conductive pathway (pathway facilitating the motion of charges)
• Resistor (Any bulb or motor requiring electricity for work)

---

Circuit Diagram Examples

[Click Here for Previous Year Questions]

In the following circuit diagram, three 5 V batteries are used to power a circuit containing three light bulbs.

The above circuit diagram depicts that the light bulbs are connected to each other in series. But it is not always necessary to connect them in series and the three cells connected by wires. But it should be noted that it doesn’t necessarily need to be connected in series. 

---

Components of a Circuit Diagram

[Click Here for Sample Questions]

A circuit diagram is a representation of an electrical circuit, therefore, its components are similar to that of an actual circuit. These components help in understanding and analyzing the circuit diagram in a better way. This analysis could be easily done with the help of the diagrammatic and symbolic representation of the components of a circuit diagram.

Electric Cell

The very first and the most essential component is an electric cell. It works as a source of current. And in its symbolic representation, the larger terminal is said to be positive whereas the smaller one is the negative terminal. 

Electric Cell

Battery

Another essential component of an electrical circuit diagram is a battery which is a combination of cells. Its functions are defined similar to that of a cell and its diagrammatic representation could also be studied similar to that of a single cell.

Battery

Wire Joint

In a few circuit diagrams or in an electrical circuit, one device has to be connected to the other device and this is done using the wires. This is represented by drawing blobs at their point of connectivity.

Wire joint

Wires crossing without joining

In the circuit diagram, when the wires do not touch each other, they are drawn without blobs. 

Wires crossing without joining

Electric bulb

This is an electrical device that uses electricity to glow and also works as a final check tool of an entire circuit diagram. 

Electric Bulb

Resistor (R)

Resistor is simply used to restrict the amount of current flow in the entire electrical circuit.

---

Types of Electric Circuit Diagrams

[Click Here for Previous Year Questions]

The different types of electric circuit diagrams are as follows – 

Block Diagram

• A Block diagram is considered one of the easiest approaches in order to display the complex electrical circuit in its simplest and most understandable form.
• In this approach, the complex interconnections or wiring are not actually considered so far, rather it displays the functioning of the principal components of an electric circuit.
• It depicts them in the form of blocks which is its main feature.
• The interconnecting lines tend to showcase the relationship between these blocks.

Schematic Circuit Diagram 

• The schematic diagram is another approach to illustrate an electric circuit.
• It displays all the electrical components & interconnections of an electrical circuit by employing systemized symbols and lines. 
• These diagrams are employed in the form of series and parallel combinations and the accurate linking between their terminals.
• For instance, while drawing a schematic diagram of a voltage amplifier, symbols must be employed for displaying the electrical components and lines to present the interlinking between their terminals.

Pictorial Circuit Diagram 

• The pictorial circuit diagram is one of the fundamental and very important forms of diagrams that use only a set of simple images of electrical components.
• These diagrams usually present a sketch of any particular electrical components that are used in an actual circuit and the same goes with the interconnections between these.
• These circuit diagrams are easy to understand due to their simpler physical appearance.

---

Things to Remember

• Circuit Diagram is a representation of an electric circuit. It is a graphical demonstration of an electrical circuit.
• The electrical circuits are represented through the lines that denote the wires.
• A circuit diagram is composed of various elements such as an electric cell, battery, wire joint, electric bulb, and resistor.
• A Block diagram is considered one of the easiest approaches in order to display a complex electrical circuit in its simplest and most basic form.
• The schematic diagram displays all the electrical components & interconnections of an electrical circuit by employing systemized symbols and lines.
• The pictorial circuit diagram is one of the fundamental and very important forms of diagrams that use only a set of simple images of electrical components.

Also Read:

---