Chapter 10 Generators and regulators

A _______ consists of a voltage regulator, current limiter, and a reverse-current cutout relay mounted as a single unit.

three-unit regulator

A voltage regulator controls generator output by...

varying current

What device is used to convert AC, which has been inducted into the loops of the armature of a DC generator, into DC?

A commutator and brush assembly

DC generators are classified as shunt-wound, series-wound, or __________, according to the manner of connecting the field coils with respect to the armature.

compound wound

In some generator systems a _______ device is installed that will reduce the generator voltage and current whenever the maximum safe load is exceeded.

current-limiting

If a generator is equipped with a vibrator-type 3 unit regulator, the actual time the voltage regulator points remain open...

depends on the load carried by the generator.

The generator ________ support the armature bearings and are mounted at each end of the field frame.

end frames

The shunt-wound generator is referred to as a ______ -wound generator.

parallel

A shunt wound generator is also known as a .....

parallel wound generator

The process of balancing generators is often referred to as _______ the generators.

paralleling

The poles of a generator are laminated to...

reduce eddy current losses

Assuming that all systems are operating normally, as the aircraft's electrical load is increased, the generator output voltage will....

remain constant and the amperage output will increase

When current to the field coil is turned off, a small portion of magnetism will remain in the field; this is called _______ ?

residual magnetism

A voltage regulator controls generator voltage by changing the...

resistance of the generator field circuit

The ____________ controls the main output current of the generator to prevent reverse current.

reverse- current relay

Generally speaking, generators that produce small amounts of electrical power utilize _________ magnet fields and high-power generators utilize _______ fields.

1. Permanent 2. Electromagnet

The voltage induced in a conductor moving across a magnetic field depends on two principle factors: the _______ of the field and the_______ with which the conductor moves across the lines of force.

1. strength 2. Speed

In a generator, the voltage produced depends on three factors; the ______ at which the armature rotates, the number of _______ in series in the armature, and the _______ of the magnetic field.

1.Speed 2. Conductors 3. Strength

In installations where the ammeter is in the generator or alternator output lead and the regulator system does not limit the maximum current that the generator or alternator can deliver, the ammeter can be redlined at...

100

To what depth is the mica insulation between the commutator bars of a dc generator undercut?

Approximately 0.02 in

The rotating wire loop, or coil, in a generator is called the ________, or rotor.

Armature

An electric generator can be defined as a machine that changes mechanical energy into __________ energy.

Electric

Electricity is produced in a generator through the process of _________ induction.

Electromagnetic

What is the method used for restoring generator field residual magnetism?

Flashing the Field

A starter generator is typically controlled by a unit referred to as a GCU which stands for ______.

Generator control unit

If the points in a vibrator-type voltage regulator stick in the closed position while the generator is operating, what will be the probable result?

Generator output voltage will increase

_________ brushes contain a lubricating additive that improves brush conductivity and wear characteristics.

Instant filming

What types of brushes can be replaced on a starter-generator without seating?

Instant filming brushes

What is the purpose of a reverse-current cutout relay?

It opens the main generator circuit whenever the generator voltage drops below the battery voltage.

A simple way to determine the direction of current flow is to use the _________ rule for generators.

Left-hand

___________ are a combination of a generator and starter housed in one unit.

Starter- Generator

A __________ is a switching device that reverses the external connections to the armature at the same time that the current reverses in the armature.

commutator

Starter-generators are typically found on which of the following types of aircraft?

Turboprop and small, turbine-powered aircraft

A typical DC generator uses a commutator assembly to create the electrical contacts between the rotating _______ coil and the stationary ______.

armature Brushes

In a generator the _____ connect to the slip rings or commutator to carry current from the rotating armature within the generator.

brushes

In most generators, the magnetic field poles are wound with coils of wire called _______.

field coils

The heavy iron or steel housing that supports the field poles of a generator is called the ________, __________, or _________

field frame, field ring, or field housing

Some starter-generators employ a drive shaft _______, which is used to protect the engine's gear box in the event the generator mechanically fails and cannot rotate.

shear section

The only practical method of maintaining a constant voltage output from an aircraft generator under varying conditions of speed and load is to vary the..

strength of the magnetic field

Many brushes incorporate a _______ in order to indicate the service life remaining on that particular brush.

wear groove