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

Good, everyone; I am glad to be bringing this publication to us at this point. Taking part in the class was quite educating, interesting, and fun and I hereby present my entry, so let's begin...

Source

Write two differences between current and voltage.

Two differences between current and voltage:

1. Direction of Flow:

• Current: Undergoes electron flow, that is, it flows from negative terminal to positive terminal.
• Voltage: Refers to the potential variation between two points and doesn't flow in a particular direction.

2. Effect and Measurement:

• Current: Is measured in amperes (A), and with the effect of transferring energy via a circuit such as lighting a bulb.
• Voltage: Is measured in volts (V), and with the effect of pushing or driving electric current via a circuit such as the "pressure" that pushes water through a hose.

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Write two differences between AC electricity and DC electricity.

Two differences between Alternating Current (AC) electricity and Direct Current (DC) electricity are:

1. Direction of Current Flow:

• AC Electricity: Depending on the frequency, the direction of the flow of current cyclically changes, usually 50 or 60 times per second.
• DC Electricity: The direction of flow of current stays constant, flowing from the positive terminal to the negative terminal.

2. Transmission and Application:

• AC Electricity: Very suitable for long-distance transmission as a result of its capacity to be transformed to high voltages, mitigating loss of energy. Usually employed in households, industries, and businesses.
• DC Electricity: Normally employed for low-voltage applications like electronic devices, renewable energy systems (solar panels for example), and automotive systems. Not suited for long-distance transmission as a result of loss of energy.

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Write the difference between an AC motor and a DC motor.

The differences between the AC motor and DC motor are shown in the table below:

Aspects	AC Motor	DC Motor
Power Source	Powered by alternating current electricity	Powered by direct current electricity
Construction	Have stationary (stator) and moving (rotor) parts. While the stator connected to the AC power source, the rotor is connected to the load	Have stator as the stationary part and armature is the moving part. While the stator is connected to the DC power source, the armature is connected to the load
Principle of Operation	Functions on the electromagnetic induction principle	Functions on the electromagnetic attraction and repulsion principle
Speed Control	Controlled by the use of variable frequency drives (VFDs) or by the adjustment of the AC power supply frequency and voltage	Controlled by the use of variable resistor or by the adjustment of the DC power supply voltage
Applications	Commonly utilized in industrial applications like conveyor belts, fans, and pumps	Generally utilized in applications requiring low voltage and high torque like robotics, electric vehicles, and medical equipment

Furthermore, although AC motors are controlled by the use of VFDs, they are more complex to control than DC motors. In addition, AC motors are commonly more effective than DC motors, specifically at high speed. AC motors also are generally cheaper than DC motors.

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

Two main differences between these starters are:

1. Starting Method: While DOL starters have the motor directly connected to the power supply, Star-Delta starters, during starting, make use of a star configuration and thereafter switch to a delta configuration. But Forward-Reverse starters can have the motor started both in forward and reverse directions.

2. Control and Protection: DOL starters make provision of simple on/off control, while Star-Delta starters make provision of mitigated inrush current course of starting. Forward-Reverse starters make provision of control and protection for each of the forward and reverse directions.

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

C. Make the specifications of the motor shown.

From the motor shown in the class, the specifications are as follows:

• KW= 45.0
• HP = 60.0
• RPM = 2960
• Ampere = 76.0
• Voltage = 415
• Hz = 50
• PF = 0.89

Find out the current of your home's 220 volts, 5 HP motor (Follow Figure 2.3).

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

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The lesson was educating and enjoyable. Thanks for coming along with me, I am inviting @saintkelvin, @gbenga01, and @alli001

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