KTU syllabus EST 130 first year electronics engineering includes inductor colour coding. https://youtu.be/iwj2K5XXhNw

1. INDUCTORS
EST 130
KTU Exam easy study

2. INDUCTOR
An inductor is a passive electronic component that opposes
sudden changes in current.
Inductors are also known as coils or chokes. An inductor is
basically a coil of wire wound on a core.
Inductor is Represented as L.
Unit of Inductor is Henry,H
Inductors are normally available in H,mH or μH

3. Applications of Inductors
 Inductors temporarily store energy in the form of magnetic field and then
releases it back into the circuit.
1. Choke
2. block AC pass DC
3. As filter
4. Store and transfer energy
5. Tuning Applications -LC (inductor / capacitor) "tank" circuits
6.Communication circuits
1. Radar

4. By Right hand Thumb rule,When a current carrying
conductor is placed in magnetic field, The thumb
points in the direction of current flow . The fingers
point in the direction of magnetic field.This property
is used in Inductors

6.  Energy stored in capacitor = ½ CV
 Where C= capacitance,V= voltage applied
 Energy stored in Inductor = ½ LI
 Where I = current flowing through the inductor,L= Inductance

7. Self Inductance
 The property of the coil to oppose any change in flow of current through the coil
by an induced emf is called Self Inductance.
 The EMF induced is given by e =−L 𝑑𝑖/𝑑𝑡

8. Mutual inductance
 When two coils are brought near to each other the
magnetic field in one of the coils tend to link with the
other.
 This leads to the generation of voltage in the second
coil.
 This property of a coil which affects or changes the
current and voltage in a secondary coil is called mutual
inductance.

9. Inductor symbol

11. Specifications of Inductor
1) Inductance value:
The value of inductance is measured in terms of its inductance value and is expressed in henries, millihenries and microhenries.
2) Resistance:
Resistance is the ohmic value of an inductor wire, which is expressed in ohms.
3) Frequency range:
The frequency range is the maximum frequency up to which the inductor can work safely.
4) Quality factor:
Reciprocal of the power factor is the quality factor. It is the ratio of inductive reactance (XL) to the resistance (R) of the coil.
For good coil, Q must be high and R must be low.
i.e. Q-factor=XL/R
5) Power loss:
The loss in the coil is due to the copper wire, stray capacitance and resistance of the coil. Less the power loss greater will be the quality of the coil.
7) Current rating:
Current rating is the operating current of an inductor and it is measured in Amps.
8) Temperature coefficient:
The temperature coefficient represents the stability in inductance value with change in temperature. It is expressed in ppm/°c.

12.  The colour code table for the inductor is given below.
To identify the value of inductor the following steps are used:
• Hold the inductor so that colour bands should start from the left-hand side.
• Read the bands from left to right.
• The first band indicates the first digit, the second band indicates the second digit, the third
band indicates the multiplier or number of zeroes to be addedafter the second digit
and the fourth band indicates the tolerance in percentage.
Inductance Colour Coding

14. Thankyou