Rectifiers And Battery Chargers Part B

Question 1

What is a rectifier?

Answer 1

A device that changes ac to dc

Question 2

A single phase full wave bridge rectifier has a frequency of 60 Hz. What is the ripple frequency of the load?

Answer 2

120 Hz

Question 3

A three phase half wave rectifier has a frequency of 60 Hz. What is the ripple frequency of the load?

Answer 3

180 Hz

Question 4

A three phase full wave rectifier has a frequency of 60 Hz. What is the ripple frequency of the load?

Answer 4

360 Hz

Question 5

Four of the eight ends of the two centre tapped transformer secondary windings are solidly connected to form the _________ rail if the rectifier.

Answer 5

Negative

Question 6

The diodes pressed into the fins of a heat sink form part of the __________ rail.

Answer 6

Positive

Question 7

What are two (2) main sections of a battery charger?

Answer 7

Transformer

Rectifier

Question 8

What happens to the volts per turn on the transformer primary when the selector is changed from 12V Low to 12V High.

a) increases
b) decreases
c) stays the same

Answer 8

a) increases

Question 9

If the battery voltage is 11.2Vdc, the Vpeak of the rectifier output 17V and the charger Vdc avg output is 10.8Vdc would the battery be charging?

a) Yes
b) No

Answer 9

a) Yes

Question 10

As the battery is charged, what happens to the current to the battery over time?

a) increases
b) decreases
c) stays the same

Answer 10

b) decreases

Question 11

Of the Vpeak output of the battery charger is normal, but the Vdc avg is half the expected value, what is most likely wrong with the charger?

a) the transformer has failed
b) the timer has failed
c) the selector failed to change the tap properly
d) one pair of diodes has failed

Answer 11

d) one pair of diodes has failed