6.11 electrical cables and connectors Flashcards
what is the normal current rating of a cable
the amount of current it will carry without sustaining a temperature rise sufficient to cause the value of insulation resistance to deteriorate to an unacceptable level, or without exceeding a specified voltage drop
where can you see cable rating
current rating is stamped on the outersheath or colour identification related to current ratings
what 2 metals are wires made of
copper
aluminium
when replacing a aluminum wire what is reccomended
consider copper wire with similar characteristics
how much higher is the resistance of aluminum wire compared to copper
1.6x higher than copper resistance
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how much lighter is an aluminium is an aluminium conductor than a copper conductor
approx half the weight
define cable
2 or more wires that are insulated separately within same outer insulation
what is a wiring harness
multiple insulated wires are bound together with lacing tape etc
what is the difference in wires for unpressurised areas vs pressurised area
unpressurised areas have thicker insulation and more robust wires
why hasnt nyvin been used on aircraft since 1990s
heavy
where is efglas found
engine circuits due to high temp resistance
what cable has replaced nyvin and minyvin
thin wall cables
what is used for maximum wire flexibility
stranded copper conductor
what voltage must wire insulation be resistant to
600v
how to prevent magnetic field from forming
two-conductor twisted cable is used to carry current
this cancels out the magnetic field
what is a coaxial cable used for
radio receivers and transmitters
what is a coaxial cable
central conductor surrounded by an insulator and a second conductor
why are some wires shielded
to prevent sensitive info from being lost or corrupted
how much of exposed wire be shielded minimum
85% of exposed are should be shielded
how does AWG sizing system work
smaller the wire, bigger the gauge
what should the electrical resistance of a properly designed and controlled crimp joint be?
should be equal to or less than the resistance of an equal section of wire
what is a connector
a semi permanent connection to avionic components or equipment
