DAY 4 Circuit Elements Flashcards
Saves weight
Must have a good connection
Single wire system
Resistance of a conductor is affected by 3 items.
Physical Characteristics
Dimensions
Temperature
Ability of a material to resist the flow of electrons. Opposite of conductivity
Resistivity
Resistance varies directly with the conductor’s length. As length increases for a given conductor, its resistance ________. The resistance of a conductor varies inversely with its cross-sectional area. As the conductor’s cross-sectional are increases, resistance _________.
answer;
increases
answer;
decreases
Aircraft wire is measured by the American ________, with the larger numbers representing the smaller wires. The smallest size wire normally used in aircraft is 22-gauge wire, which has a diameter of about 0.025 inch. Conductors carrying large amounts of current are typically of the 0000, or four aught size, and have a diameter of about 0.52 inch.
Wire Gauge system
_______ is a positive coefficient of resistance.
Temperature
Increase in _______, increase in resistance.
Temperature
There are two remote control switch types of relays.
Fixed core ( core is stationary)
Coil of wire
Solenoid - a coil of wire with a movable core.
Spring separates contacts.
Current flows, produces magnetic field, pulling contacts close.
Movable Core (Electromagnet)
Soft metal alloy melts when current flow becomes excessive.
Slow blow.
Will take some current.
Has a surge spring.
Fuse
CB trips (pops out).
Reset once.
Investigate further if it trips again.
Trip free.
Thermal.
Opens a circuit when excess current heats an element.
Magnetic.
Utilize the magnetic field caused by current in a circuit.
Circuit Breakers.
Typical CB’s.
Push/pull.
Push to reset.
Toggle.
Automatic Reset.
Opens when excessive current flows.
Closes when circuit cools.
Open circuit
Break in conductive path.
Short Circuit
Path from power source (-) to (+) without passing through a load.
