6.11 Flashcards
What is the prime consideration for aircraft cables
reliability
what are the requirements for aircraft cables
Minimum weight and dimensions
Resistant to fluids
Non flammability
Wide range of operating temperatures
Resistant to abrasion
what is the rating of a cable
the amount of current it can carry without sustaining a significant temperature rise
what factors affect the rating of a cable
If the current is continuous or intermittent
what is a wire
an isolated single solid conductor or stranded conductor surrounded by insulation
what are the 2 most common used materials for wires
copper and aluminium
what is the advantage of aluminium over copper
it is lighter
what is the advantage of copper over aluminium
it needs less space and is more conductive and doesn’t crystallise and break
What is a cable
2 or more wires that are insulated separately within the same outer insulation
what is a wire harness
multiple insulated wires are bound together with lacing tape, metal bands or another restriction
what is nyvin and is it used in modern aircraft
a general purpose airframe cable that was one of the first and is no longer used
how many forms of nyvin are there
5
what is efglas
a high temperature resistant cable
what is a thin wall cable
general purpose cable that has replaced nyvin
what are the three different temperature ratings for a wire
up to 100/150ºC is normal
Up to 260ºC is high temperature
Up to 1093º for 15 mins is fire resistant
what is a shielded cable and why is it used
used to stop the magnetic field caused by current by either cancelling it out or surrounding it so it can’t escape
what can be used to measure the size of a solid conductor in a wire
a wire gauge stencil
how does a wire gauge stencil measure the size of a wire
the insulation is stripped and the conductor is slotted in until it cannot fit then it is pushed through to see the size
What does a dashed green line signify
the wire is measured in metric
what are the 2 different types of markings on cables and wires
manufacturer part number and the instillation system its a part of
What are the 2 types of wire markings
direct and indirect
What is a high tension cable used for
high voltages in engine ignition systems
what does a co-axial cable transmit
radio frequency energy
what is a co-axial cable designed to prevent
radio frequency interference
what does crimping do
connects a wire conductor to a terminal or contact without using solder
how does crimping work
attaches a terminal or contact end to a conductor by pressure, forming or reshaping a metal barrel together with the conductor
what is the crimping process (rules)
select correct stripping tool, stripping the wire to the correct size, making sure lay of cable strands is correct, use correct connector, use correct crimping tool , use a test piece, crimp the contact and wire
what is splicing
joining 2 or more wires together for repair or modification
what are the 2 forms of splicing
in-line repair splice and fly-lead attachment splice
where can in-line splices not be used
autopilot circuits, inside electrical conduit trunking, fire-protection circuits, oxygen systems,coaxial cable, multi-core cable
what is the purpose of a turret head
to position the contact correctly
what is a connector
a device that provides a semi-permanent connection to avionic components or equipment
What does a circular connector consist of
a receptacle and a plug
when installed with an axis that is horizontal where is the master keyway
at the top
what is the order for contact configuration for letters
upper case then lower case then double upper case then double lower case
what letters cannot be used for contact counting
I,O,Q,l,o
as the AWG number gets higher does the size of the wire get bigger or smaller
smaller
