Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Electrical Systems
Airframe written
| Question | Answer |
|---|---|
| What is the advantage of a current limiter? | It will take overload for a short period of time |
| Certain transport aircraft use AC electrical power for all normal operation and battery furnished DC electrical power for standby emergency use. In aircraft of this type that operate no DC generators, the batteries are kept charged by | rectifiers which use the aircraft's AC generators as a source of power |
| The strength of the core of an electromagnet depends upon the material from which it is constructed and which of the following? | The number of turns of wire in the coil and the amount of current (amperes) passing through the coil |
| What kind of switch should you install in a single wire circuit that required the switch to be manually held in the ON position? | Single-pole, single-throw(SPST), two-position normally open |
| The commutator of a generator | changes alternating current produced in the armature into direct current as it is taken from the armature |
| How can the direction of rotation of a DC electric motor be changed? | Reverse the electrical connections to either the field or armature windings |
| The poles of a generator are laminated to | reduce eddy current losses |
| If any one generator in a 24-volt DC system shows low voltage, the most likely cause is | an out-of-adjustment voltage regulator |
| Electrical connectors used in the aircraft assemblies should meet which of the following specifications? | Military Specifications (MS) |
| If a wire is installed so that it comes in contact with some moving parts, what protection should be given the wire? | Pass through conduit |
| To test generator or motor armature windings for opens, | place armature in a growler and connect a 110V test light on adjacent segments; light should light |
| Which statement relating to electric wiring is true? | When attaching a terminal to the end of an electric cable, it should be determined that the strength of the cable-to-terminal joint is at least equal to the tensile strength of the cable itself. |
| The pin section of an AN/MS connector is normally installed on | the ground side of a circuit |
| Electric wiring installed in aircraft without special enclosing means (open wiring) offers the advantages of ease of installation, simple maintenance, and reduced weight. When bundling open wiring, the bundles should | be limited as to the number of cables to minimize damage from a single electrical fault |
| A voltage regulator controls generator output by | varying current flow to generator field coil |
| The major advantages of alternating current (AC) over direct current (DC) is the fact that its current and voltage can easily be increased or decreased | by means of a transformer |
| When selecting hardware for attaching bonding connections to an aircraft structure, which of the following should be considered? | Mechanical strength, ease of installation, amount of current to be carried |
| During inspection of the terminal strips of an aircraft electrical system, it should be determined that | the terminal studs are anchored against rotation |
| The voltage output of an alternator may be regulated by controlling the | voltage output of the dc exciter |
| The circuit breaker in the instrument lighting system protects the | wiring from too much current |
| When considering an alteration, the criteria upon which the selection of electric cable size should be based are | current-carrying capacity and allowable voltage drop |
| What is the most accurate type of frequency measuring instrument? | Integrated circuit chip having a clock circuit |
| What is normally used to bond noncontinuous stainless steel aircraft components? | Copper jumpers |
| In a generator, what eliminates any possible sparking to the brush guides caused by the movement of the brushes within the holder? | The brush pigtail |
| How many cycles of AC voltage are produced in a six-pole alternator of the revolving-field type for each revolution of the rotor? | Three |
| What is the purpose of the selection of derated switches for known continuous load current applications? | To obtain reasonable switch efficiency and service life |
| To what depth is the mica insulation between the commutator bars of a DC generator undercut? | Equal to the width of the mica |
| How does the magnetic brake used to stop rotation of an electric motor armature operate? | A friction brake is applied by a spring and released by a magnet |
| Residual voltage is a result of magnetism in the | field shoes |
| Aluminum wire must be stripped very carefully because | individual strands will break easily after being nicked |
| If a generator is equipped with a vibrator-type voltage regulator, the actual time the voltage regulator points remain open | depends on the load carried by the generator |
| The nominal rating of electrical switches refers to continuous | current rating with the contacts closed |
| A series-wound DC electric motor will normally require | more current at low RPM than at high RPM |
| A CSD unit drives a generator through the use of | a variable hydraulic pump and hydraulic motor |
| Bonding connections should be tested for | resistance value |
| What type of instrument is used for measuring very high values of resistance? | Megohmmeter |
| CSD generators are usually cooled by | oil spray |
| In an AC circuit with no phase lead or lag, which is true? | Real power equals apparent power |
| To help minimize radio interference a capacitor will largely eliminate and provide a steady direct current if the capacitor is connected to the generator in | parallel |
| Which of the following should be accomplished in the installation of aircraft wiring? | Locate the bundle above flammable fluid lines and securely clamp to structure |
| How are generators rated? | Amperes at rated voltage |
| In troubleshooting an electrical circuit, if an ohmmeter is properly connected across a circuit component and some value of resistance is read, | the component has continuity and is not open |
| Which type of DC generator is not used as an airplane generator? | Series wound |
| What should be used to protect wires from chafing when they must pass through bulkheads, firewalls, ribs, etc.? | Suitable grommet |
| When necessary during operation, CSD disconnect is usually accomplished by | a switch in the cockpit |
| A circuit breaker is installed in an aircraft electrical system primarily to protect the | circuit and should be located as close to the source as possible |
| The inductor-type inverter output voltage is controlled by the | dc stator field current |
| Which motor would be most likely to have an armature brake? | Landing light retraction motor |
| An aircraft electrical circuit control relay is | an electronically operated switch |
| Oil canning of the sides of aluminum or steel electrical junction boxes is considered to be | a shorting hazard |
| In aircraft electrical systems, automatic reset circuit breakers | should not be used as circuit protective devices |
| Which of the following is most likely to cause thermal runaway in a nickel-cadmium battery? | Excessive current draw from the battery |
| If the reverse current cutout relay contact points fail to open after the generator output has dropped below battery potential, current will flow through the generator armature | opposite the normal direction and through the shunt field in the normal direction |
| If several long lengths of electrical cable are to be installed in rigid conduit, the possibility of damage to the cable as it is pulled through the conduit will be reduced by | dusting the cable with powdered soapstone |
| The pole pieces or shoes used in a DC generator are a part of the | field assembly |
| What is the frequency of an alternator dependent upon? | RPM |
| One purpose of a growler test is to determine the presence of | a shorted armature |
| Electric wire terminals for most aircraft applications must be what type? | ring |
| Integrated drive generators (IDG) employ a type of high output AC generator that utilizes | a brushless system to produce current |
| If the Integrated Drive Generator (IDG) scavenge oil filter is contaminated with metal, you should | remove and replace the IDG |
| A circuit protection device called a current limiter is essentially a slow-blow fuse and is designed to be used in | heavy power circuits |
| (Refer to Figure 19.) Upon completion of the landing gear extension cycle, the green light illuminated and the red light remained lit. What is the probable cause? | Short in the up limit switch |
| The most common method of regulating the voltage output of a compound DC generator is to vary the | current flowing through the shunt field coils |
| Aircraft electrical junction boxes located in a fire zone are usually constructed of | stainless steel |
| When using an ohmmeter to check the continuity of a generator field coil, the coil should | show very low resistance if it is a series field coil |
| When adding a rheostat to a light circuit to control the light intensity, it should be connected in | series with the light |
| Which of the following are the major parts of a DC motor? | Armature assembly, field assembly, brush assembly, and end frame |
| The navigation lights of some aircraft consist of a single circuit controlled by a single switch which has an ON position and an OFF position, with no additional positions possible. This switch is referred to as a | single-pole, single-throw (SPST), two position switch |
| Where is the generator rating and performance data located? | Stamped on the generator data plate |
| What is the maximum amount of time a circuit can be in operation and still be an intermittent duty circuit? | two minutes |
Created by:
mattpayne001