BE Lesson 10: Inductors

What are inductors and how are they used?

© 2012 C. Rightmyer, Licensed under The MIT OSI License, 20 July 2012

BE demo 10-1. Demonstrate a coil’s electromagnetic effect

1.5 Volt AA batteryis sufficient to pick up a paper clip.

Make: Electronics, Oreilly, Charles Platt, 2009

BE demo 10-2. Demonstrate “self-inductance” of an electromagnetic coil

Adapted from Make: Electronics, Oreilly, Charles Platt, 2009

9 vLEDLED

220

BE demo 10-2. Hookup diagram.

9 v

+

push button switch

47

LEDLED

BE demo 10-3. A simple DC motor with inductive sparking

Adapted from [Usborne, Electricity and Magnetism, Adamczyk and Law, 1993]

BE demo 10-4. Operation of a magnetic solenoid

BE demo 10-5. Operation of a Single Pole Double Throw (SPDT) relay

9 v

+

push button switch

LED LED

220 220

BE ckt 10-6. Inductive-capacitive oscillation

Adapted from Make: Electronics, Oreilly, Charles Platt, 2009

12 v

LED

330 +

1000 uf

LED

+

LM2-12 Relay

Hookup diagram for BE ckt 10-6

12 v

+

push button switch

330

LED LED

A brief summary of component characteristics that you have learned so far in this course

• Resistors impede current and consume voltage.

• Capacitors act like miniature batteries. They initially allow DC current flow but when fully charged they block DC DC current. They pass AC current.

• Inductors initially block DC current but then allow it to flow with little resistance. After the coil’s magnetic field builds to its steady state, self-inductance attempts to maintain the current at its current level until the magnetic field becomes discharged.• Resistors, capacitors, and inductors can be designed into circuits such as to cause various patterns of oscillation.