Electrics Part 2

Question 1

The primary electrical circuit:

This is made up of a few turns of -

around the core, one end of which is -

and the other end connected to ungrounded side of the contact points. A capacitor, or condenser, is wired in -

with the points and prevents -

The capacitor also hastens the collapse of magnetic field. Thus, the -

Both the capacitor and the points are wired in -

At the full register position, the breaker points -

This flow through the primary circuit causes lines of magnetic flux which cut across the -

When the primary circuit is broken by opening the breaker points, the field about the primary circuit collapses. This causes the windings of the secondary coil to be cut by the lines of force. Since the secondary coil has many thousands of windings, a very high voltage is induced to the spark-plug.

Answer 1

.
.
heavy copper wire

grounded

parallel

arching at the points themselves when opening.

primary circuit is only complete when the points are closed.

series with the primary coil.

close and the rotating magnet will induce a current flow in the primary circuit.

secondary coil windings

Question 2

A current limiter fuse in a DC generation system is used to :

Answer 2

allow a short term overload before rupturing.

Question 3

In aeronautics, the most commonly used batteries are NiCd because…

Answer 3

they weigh less than lead-acid batteries.

Question 4

On most transport jet aircraft, the low pressure pumps of the fuel system are supplied with electric power of the following type:

Answer 4

115 V AC

Question 5

A relay is :

Answer 5

a magnetically operated switch.

Question 6

Because the connection in parallel of electrical systems on an AC bus bar, isolation of individual equipment:

Answer 6

Decreases the bus bar current consumption.

Question 7

The so-called “hot buses” or “direct buses” are:

Answer 7

directly connected to the battery.

Question 8

An AC generator driven by a CSD unit :

Answer 8

requires a voltage controller to maintain constant voltage under load.

Question 9

A test to assess the state of charge of a lead-acid battery would involve :

Answer 9

comparing the “on-load” and “off-load” battery voltages.

Question 10

The voltage of a fully charged lead-acid battery cell is :

Answer 10

2.2v

Question 11

A fault protection circuit in a fire detection system will:

Answer 11

inhibit the fire detector when the detection line is connected to ground.