Power Source Filters

Question 1

What does a filter section of a power supply remove?

Answer 1

It removes ripple

Question 2

what does removing ripples do?

Answer 2

flattens the pulsating DC wave to make a more consistent load line

Question 3

Name three characteristics of a filter circuit

Answer 3

1. Stores Energy when the current is high
2. Releases energy when current is low
3. Combination of capacitors, inductors, resistors

Question 4

What is a Capacitor

Answer 4

A voltage storage device

Question 5

what type of capacitor is used?

Answer 5

Electrolytic Type

Question 6

How does a capacitor work?

Answer 6

stores voltage as sine wave builds and releases voltage as sine wave decreases

Question 7

What is an Inductor

Answer 7

a magnetic field storage device

Question 8

How does inductor work?

Answer 8

stores magnetic field as sine wave builds and releases magnetic field(current) as sine wave decreases

Question 9

What is a Resistor?

Answer 9

a voltage-dropping device

Question 10

How many Ohms is the resistor usually?

Answer 10

usually below 500 Ohms

Question 11

How many watts is the resistor usually?

Answer 11

high power rating above 2 watts

Question 12

How are capacitor filters connected in a circuit?

Answer 12

is a capacitor “C” connected in parallel with a load resistance “RL”

Question 13

the amount of voltage drop before the capacitor begins to charge again is called _____ _____

Answer 13

ripple voltage

Question 14

What controls the amount of capacitor discharge between voltage peaks

Answer 14

the RC time constant of the capacitor and load resistance

Question 15

what were to happen if the load resistance and capacitance are large

Answer 15

the ripple voltage will be small, resulting in a smooth output

Question 16

advantages of a capacitive filter

Answer 16

1. Low cost
2. low ripple at low load

Question 17

disadvantages of capacitive filter

Answer 17

1. High ripple at high load

Question 18

over time what could damage circuit fuses and diodes

Answer 18

surge currents

Question 19

How does an L-section resistive filter reduce surge currents?

Answer 19

using a current-limiting resistor

Question 20

How should the resistor be connected in an L-section resistive filter

Answer 20

in series with the rectifier

Question 21

how does the L-section inductive filter reduce surge currents?

Answer 21

using a current-limiting inductor(coil) L1

Question 22

how do inductors used as series elements oppose changes in current

Answer 22

by creating a counter electromotive force (CEMF) or counter voltage

Question 23

what happens to the pulses not blocked by the inductor?

Answer 23

they are bypassed by the capacitor

Question 24

True or False?
The inductor tends to block the pulsating DC voltage

Answer 24

True

Question 25

What are the two types of Pi Filters

Answer 25

1. Inductive
2. Resistive

Question 26

when money is a factor, the inductor is sometimes replaced by ____ in a pi-section filter

Answer 26

resistor