"SLC21/WK3: Introduction to Basic Electrical Motors, Switchgear, and Motor Starters"

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This is @max-pro from, #Bangladesh}

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Assalamu Alaikum steemian friends hope you all are well. By the grace of Allah I am also well. Today I came to participate in this "SLC21/WK3: Introduction to Basic Electrical Motors, Switchgear, and Motor Starters" excellent learning engagement competition organized by our electrical teachers @mahadisalim and @solaymann. This is a very nice contest where we get to know basic electrical motors, switchgears and motor starters. Here I will answer some questions step by step.

A:- Write two differences between current and voltage.

The two main differences between current and voltage are

Current	Voltage
It is the flow of electric charge. Meaning current is the flow of electrons through a circuit. Its unit is ampere.	This is the electrical potential difference between two points. It is the electrical force that forces the electrons to flow. Its unit is volt.
It refers to the flow of charge through an electrical circuit and it consumes the energy required to do work in a circuit.	It basically creates an electrical effect that helps the charges to flow. It acts as a force to make the current flow.

A:- Write two differences between AC electricity and DC electricity.

The two main differences between AC electricity and DC electricity are

AC Electricity	DC Electricity
in which the direction and value of the current flow changes regularly. It can be sine wave or in various forms.	In this the direction and value of current flow is constant and does not change.
It is usually found in power supply lines (ie: house electrical connection). It is more effective in supplying power to large areas.	It is available through batteries, solar panels etc. and is used in devices like mobiles, laptops.

AC Electricity	DC Electricity

A:- Write the difference between an AC motor and a DC motor.

There are a few major differences between AC motors and DC motors. These differences between AC motors and DC motors make them suitable for different applications and uses. It is explained below.

AC motor	DC Motor
It receives power from alternating current (AC), where the direction of current changes with time.	It receives power from Direct Current (DC) where the current flow is unidirectional.
Generally used in large machinery or industrial fields. Such as pumps, air conditioners and fans.	Small equipment or where specific speed is required. Such as used in small appliances, robots, electronic devices etc.
More durable and reliable as it does not have a commutator.	DC motors require maintenance after some time because of the commutator and brushes.

Ac Motor	Dc Motor

A:- Write two main differences between DOL, Star-Delta and forward reverse starter.

DOL, Star-Delta and Forward Reverse Starter are three different types of induction motor starters, and there are some important differences between them. The two main differences are given below,

DOL (Direct On-Line) Starter :-

• It starts the motor by connecting it directly from the line. As a result the starting current of the motor is very high and the motor starts quickly.

• Generally used in small size motors where starting current is not a concern. It is compact and easy to use.

Star-Delta Starter :-

• During starting the motor first starts in star configuration, so that the starting current is low and later it changes to delta configuration.

• It is used for large motors, where the starting current has to be reduced and then run to full power. It is generally used for large machinery or mechanical loads.

Forward Reverse Starter :-

• It enables the same motor to rotate in two different directions, switches are used for forward rotation on one side and reverse rotation on the other. But there is no specific configuration for starting current.

• It is used in applications where the motor needs to be driven in reverse (such as conveyor belts, fan systems), and it supports forward and reverse rotation.

B. Write the names and pictures of the electrical switchgear used in your home.

The electrical switch breaker in our house is called MCB. MCB (Miniature Circuit Breaker) An automatic circuit breaker that protects the circuit from hazards caused by over current or short circuit in the power supply. It is a small size device that can be easily installed and automatically shuts down the system in case of power failure.

MCB is generally used in low voltage systems and its main function is to prevent overload and short circuit. It can reset manually or auto. Protecting the circuit through MCB increases the stability and safety of power supply. I have given its picture below.

MCB

C:- Make the specifications of the motor shown below.

source

• KW = 37.0

• HP = 50.0

• RPM = 2960

• Ampere = 62.8

• Voltage = 415

• Hz = 50

• PF = 0.80

Find out the current of your home's 220 volts, 5 HP motor.

Our teacher showed above 1 Hp = 746 w. So according to that below how much 5 HP will be shown.

• 5 HP = 3730 W

D. Draw the power circuit of the star delta starter and name the devices used.

Above diagram is the power circuit of star delta starter. So now the names of the main devices used are given in tabular form.

Power circuit of star delta starter

Motor	Generally 3-phase induction motor is used.
Thermal Relay	Used to provide protection to motor due to overheating.
Contactors (K1, K2, K3)	Used to change the star and delta configuration of the motor. Three contactors are used for a star connection. One for delta connection and one for motor relay protection.
Timer	Used for changing star and delta configurations.
Switch	Start/stop switch used to start or stop the motor.
FCrail Fuse	Protects the motor due to over current.

These devices are used in the power circuit of the star delta starter so that the motor can be started efficiently and safely. So here we have done some work in a very practical way. So it's a very nice learning competition. I am very happy to participate in this contest.

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So I am Inviting my lovely Steemian friends @kouba01, @irawandedy, @selina1 to Participate in this Competition.

Thank You So Much For Reading My Blog.