Table of Contents

## Electric Circuit

Electric Circuit Meaning in English | Electric Circuit Definition In English | Definition of electric circuit.

The medium that is required for the electric current to flow is called the Electric Circuit.

What are the types of electric circuits? | What are the types of electrical circuits?

- Ohm’s Law | Who was Omh? | 3 important formulas of Ohm
- What is a Polyphase System?
- What is Neutral In Electrical? | Purpose of Neutral Wire in electrical Circuit
- What is 3 Phase Induction Motor?| Types, structure and working principle of Three phase induction motor.

## Main 3 types of Electric Circuit

- Close Circuit
- Open Circuit
- Short Circuit

## 1. Close Circuit

The electrical circuit in which the electric current (I) meets the Positive Point of the supply source through the Load Resistence (R) from the Negative Point of the supply source. And the circuit in which electric current can flow smoothly is called a close circuit.

(Supply source can mean Battery, Generator, or our in-house Electric Supply.)

(Load Resistence (R) means a Bulb, Fan, Refrigerator, Tube Light, Moter, Electric Heater and every device that runs on electricity.)

### Examples of Close Circuit.

- Turn on the lamp and light it.
- Heating and heating of electric heater.
- Electric Moter providing reciprocating mechanical energy. Etc ..

All these functions happen because of the Closed Circuit.

### Types of Close Circuit

The Close Circuit is divided into 3 types according to the methods of adding resistance.

- Series Circuit
- Parallel Circuit
- Compound Circuit

#### Series Circuit

The electrical circuit in which two or more resistances are added. Out of which there is only one path in that circuit for the current to flow, it is called the Series Circuit.

Connection of all Load Resistance of this circuit is done as a chain.

Means the second terminal point of the first resistance, from the first terminal point of the second resistance,

The second terminal point of the second resistance is connected to the first terminal point of the third resistance.

The first Terminl Point of the first Resistance and the Second Terminal Point of the last Resistance are used to supply.

#### Properties of Series Circuits

- The Electric Circuit has only one path for the current to flow, and the entire current of the circuit passes through each resistance. I = V ÷ R and I = I1 = I2 = I3 etc.
- Each resistance has a current equal to Ohm’s law and a voltage drop equal to the multiplier of the resistance. VD1 = I × r1; VD2 = I × r2; VD3 = I × r3
- The total (Total) of the voltage drop (VD) that occurs at each resistance is equal to the Total Supply Voltage (V) given in that Electric Circuit. V = V1 + V2 + V3
- The total resistance of a circuit is equal to all the resistance of that Electric Circuit. Meaning, when the number of Resistance in the circuit increases, then the total Resistance of the circuit also increases. According to Ohm’s theory, the total current of the circuit will also decrease. R = r1 + r2 + r3 … rn (Number Of Resistance)
- If any resistance in the circuit is broken or if the circuit is opened from somewhere, the current flow is broken and the entire circuit is closed. Because of this, no single resistance of the Series Circuit can be controlled independently.
- When equal values are added to the Resistance Series only then I × R in this way gives everyone the same Voltage, and all that Resistance do the same thing. Otherwise, the voltage is obtained according to the value of each resistance. And they work in more evidence.
- If 2 Resistance series of the same Watt and Ohm are added to the series, then the total power of the circuit is Halfway.

Example: – If 100 Watt, 2 bulbs of 250 Volt are added to the series. And if that series circuit is supplied 250 Volt then the total power of that circuit will be 50 Watt. Is the same.

#### Where is the Series Circuit used?

- Load Resistance of low Voltage Rating to add more Voltage at supply.
- To reduce the total current of the circuit.
- To achieve the objective by dropping the voltage at the required places.
- For decoration by adding to the Miniature Lamps Series of decorations.
- To add fuse. The fuse is applied in series in the circuit itself.
- To add Over Load Coil.
- To add a multiplier to a voltmeter.
- To increase Circuit Voltage by adding Torch or Battery to Low Voltage Cells Series.
- For current reading by adding ameter.

**Parallel Circuit**

The Electrical Circuit in which as many Load Resistance are added. As such, there are routes of current flowing in that circuit. It is called Parallel Circuit.

If you look in this figure, you will know that, from each Load Resistance, independent Positive And Negative Terminals coming from the supply source are connected.

#### Property of Parallel Circuit

- All Load Resistance receive independent power supply. The voltage of the power supply and the voltage received by each of the resistors are same. V = V1 = V2 = V3
- Each resistance has a current divided in proportion to its value.
- The total current of the circuit, flowing through each resistance is equal to the total current of that circuit. (I = i1 + i2 + i3 … in)
- To find the total resistance of the circuit, the total conductance (G) is calculated by totaling all the conductances. And the total conductance has to change in the total resistance.

R = 1 ÷ G - Resistance is added to the circuit. As such, the total resistance of the circuit decreases.
- The total resistance of the circuit is also less than the lowest resistance available in that circuit.
- If any resistance in the circuit is open or shot, then it does not affect any of the remaining resistance in the circuit. Each Load Resistance can be controlled independently.

**Where is the Parallel Circuit used?**

- The Parallel Circuit is used in all types of wiring. Examples: – House Wiring, Shop Wiring, Factory Wiring
- For adding common home appliances and lamps.
- To add street light.
- To add a shunt to the ammeter.
- To measure voltage by adding a voltmeter.
- To increase the current capacity by adding multiple cells together in the battery.

### Compound Circuit

The new electrical circuit that is formed by connecting the Series Circuit and Parallel Circuit is called Compound Circuit. Circuits of this type are not used in house wiring. Compound Circuits are used in the Electronics Sector. Some of the Resistance are added to their Parallel by adding some Load Resistance Series to it.

## Open Circuit

The electric circuit in which the electric current (I) does not address the source of the supply source from Positive Point to Negative Point, the path of current flow opens somewhere due to some reason. That curcuit is called Open Circuit.

### Examples of Open Circuit

- Switch off of the circuit. Or the contact of the switch is not correct.
- Blowing of fuse wire.
- The wire of the Close Circuit is broken somewhere.

## Short Circuit

The Electric Circuit in which the flow of electric current flows is complete without Load Resistance, that is, Positive and Negative points of the supply source are connected to each other without minimum Resistence, then that circuit is called Short Circuit .

Since there is no resistance in the current flowing in the Short Circuit, more current flows out of the Electric Circuit. Because of this, the insulation of the wire starts melting after heating. Many times there is a possibility of fire. If such a circuit has a proper capacity Fuse Wire, it will be heated and melted and broken. And if the MCB is working in that Electric Circuit then it becomes operate. And converts that Short Circuit into **Open Circuit**. And thus the accident or loss in that circuit can be avoided.

If you look carefully at the three main electric circuits mentioned above, you will understand that, out of these, current, voltage voltage, and resistance exist in the Close Circuit. These three zodiac signs have a special relationship. Which exist in that circuit.

Georg Simon Ohm, a famous scientist who has put this relationship between current, voltage voltage, and resistance in front of the world as a rule. Which is called Ohm’s Low.