Electrical loadsAbdulaziz - Mshal

Q1: What are the types of loads?

Q2: What do you know about resistor, capacitor, inductor?

-Resistance is a property of material due to which it opposes the flow of current through it.

-When electrons flow through any material, they collide with each other which gives rise to opposition to the flow of current.

-The unit of resistor is ohm(Ω).

Resistor

Types of resistor

There are many different Types of Resistors available to the electronics constructor, from very small surface mount chip resistors up to large wirewound power resistors.

They are described as below :1. Carbon Composition Resistors2. Carbon Film Resistors3. Metal Film Resistors4. Thick Film Resistors5. Thin Film Resistors6. Wire wound Resistors 7. Surface Mount Resistors

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CapacitorA capacitor consists of two conducting

plates separated by an insulator (or dielectric).

The symbol use for capacitor in the circuit diagram is ::

The unit of capacitor is Faraday ( F )

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Types of Capacitors

(a) Polyester capacitor, (b) Ceramic capacitor, (c) Electrolytic capacitor

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Inductor

An inductor is made of a coil of conducting wire.

An inductor is a passive element designed to store energy in the magnetic field while a capacitor stores energy in the electric field. The unit ([Henry] or [H])

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Types of Inductor

(a) air-core(b) iron-core(c) variable iron-core

Resistive Loads

- Resistive loads are loads which consume electrical energy in a sinusoidal manner. This means that the current flow is in time with and directly proportional to the voltage.

- It is a load that contains no inductance or capacitance, just pure resistance. Therefore; when a resistive load is energised, the current rises instantly to its steady-state value without first rising to a higher value.

- It includes loads such as :

Resistive Loads

- Incandescent lighting

- Electrical heaters.

Inductive Loads

- An Inductive Load is a load that pulls a large amount of current (an inrush current) when first energised. After a few cycles or seconds the current "settles down" to the full-load running current.

- Inductive loads can casue excessive voltages to appear when switched. - An Inductive Load is a load that pulls a large amount of current (an inrush current) when first energised. After a few cycles or seconds the current "settles down" to the full-load running current.

- Inductive loads can casue excessive voltages to appear when switched.

Inductive Loads

- Examples of Inductive Loads are :

- Motors- Transformers

Capacitive Loads

- A Capacitive Load is an AC electrical load in which the current wave reaches its peak before the voltage.

- Capacitive loads are loads that capacitance esceeds inductance.

Capacitive Loads

-Example of a Capacitive Load is :

-The flash of the camera.