7.7 - Electrical Wiring Interconnection System Flashcards
How would you identify a spare wire in a bundle?
Identify a spare wire in a bundle by the ‘‘spare wire’’ label and an insulating end cap NSA936601 at each end
What does EWIS stand for?
EWIS = Electrical Wiring Interconnection System
What is EWIS training based on?
EWIS training is based on EASA AMC 20-22 and FAA 120-94
The Aging Transport Systems Rulemaking Advisory Committee ATSRAC is a _____________
The Aging Transport Systems Rulemaking Advisory Committee ATSRAC is a Federal Advisory Committee
What should the minimum bend radius of a wire in a loom be?
The minimum radius of a bend in a wire loom is no less than 10X the outside diameter of the largest wire in the loom
Insulation is checked by using how much operating voltage?
Insulation is checked by using twice the operating voltage
What happens when the Voltmeter is connected across an open circuit?
When a Voltmeter is connected across an open circuit in a supply cable the Meter will indicate Voltage less than the supply Voltage
Primary Conductors are required to carry _____ currents
Primary Conductors are required to carry lighting currents
When using an ohmmeter to check a shorted resistor in a circuit, the meter will read …
When using an ohmmetere to check a shorted resistor in a circuit, the meter will read Zero ohms
Composite panel bonding test uses ______________
Composite panel bonding test uses an Insulation resistance tester
What type of Voltage does an Insulation resistance tester use?
Insulation resistance tester uses DC voltage
What is the Max bonding value for Primary conductors?
Max bonding value for Primary conductors is 0.05 Ohms
How are circuit tests on aircraft carried out? (in what order)
Circuit tests on aircraft are carried out in the following order.
Bonding, continuity, Insulation, functional (BCIF)
Exceeding 200 degrees C. Use a __________ cable
Exceeding 200 degrees C. Use a Nickel-plated cable
Oxide on exposed _____-plated cable in an insulator
Oxide on exposed silver-plated cable in an insulator
Knuckling on older type electrical cables is caused by …
Knuckling on older type electrical cables is caused by excessive pull through forces
Ohmmeter leads resistance should be less than ?
Ohmmeter leads resistance should be less than 1 ohm
To find high resistance or open circuit, do a ________ check?
To find high resistance or open circuit, do a continuity check
Equipment cable is ______________________
Equipment cable is flexible and suitable for soldering
What happens if Silver coated connector encounters Glycol de-icing fluid?
Silver coated connector encounters Glycol de-icing fluid causes a fire hazard
Aluminium oxide layer becomes _________ as temperature is increased
Aluminium oxide layer becomes thicker as temperature is increased
What is the max temperature rating of tin coated copper cable?
Max temperature rating of tin coated copper cable is 135 degrees C
Insulation resistance for wiring in the wheel-well area is what?
Insulation resistance for wiring in the wheel well area is more than 2 megaohms
Interconnect cable has insulation ______ than airframe cable
Interconnect cable has insulation thinner than airframe cable
What can a Hot stamped cable cause?
Hot stamped cable can cause wet arc tracking
When crimping wires onto a terminal, how far should the wire extend beyond the crimp?
Crimping wires onto a terminal, the wire should extend 0.8mm or 1/32 inch beyond the crimp
What ATA chapter would deal with Crimping electrical wires?
Crimping electrical wires. ATA chapter 20
What 2 things should be considered when choosing a cable?
When choosing a cable, consider current carrying capacity and allowable voltage drop
A crimped electrical terminal is suspected of high resistance. How would you verify this without disconnecting the circuit?
Measure the millivolt drop across the connection with a millivolt meter
How can insulation grip be adjusted on an AMP PIDG crimping tool?
Insulation grip can be adjusted on an AMP PIDG crimping tool by adjusting the pins
What colour is the following:
22-18 Gauge
16-14 Gauge
12-10 Gauge
How is the pin released and extracted from a Rear release connector?
Rear release connector, the pin will be released from the rear and extracted from the rear
When carrying out a millivolt drop check on a circuit, the approximate guide for correct reading is
When carrying out a millivolt drop check on a circuit, the approximate guide for correct reading is 5 millivolts for every 10 amps flowing
What is the minimum number of strands in a cable?
Minimum number of strands in a cable is 19
Over what interval does a cable have an identification tag?
Cable has an identification tag every 15 inches
Over what interval should a wire be supported?
Wires should be supported at intervals no more than 24 inches
What is the allowable bend radius for RF / Coax cable?
Allowable bend radius for RF / Coax cable is, not less than 6x the outside of the diameter of the Coax cable
What is the clearance that should be kept between wires and moving parts?
Half an inch clearance from any moving parts
Where are Zip Ties not allowed?
Zip Ties aren’t allowed near motion / control areas
What is a triaxial cable?
A triaxial cable is one which has a double shielded wire and a single core
Hot wire stamping can cause ?
Hot wire stamping can cause Dry arc tracking
When might Red plague happen?
Red plague happens with Silver plated conductors
In high temperature areas, what wire should be used?
In high temperature areas use Nickel plated copper wire
In fire zones, what wire should be used?
In fire zones use Nickel clad copper wire
The slack allowed in a wire bundle should not exceed ?
The slack allowed in a wire bundle should not exceed 1/2 inch
A blue AMP Amphenol (PIG) crimped connector should show ? dimples
A blue AMP Amphenol (PIG) crimped connector should show 2 dimples
The current carrying capacity and allowable voltage drop
22 - 18 gauge
The correct tool was used on the terminal
5 millivolts for every 10 amps flowing
Extend 0.8 mm or 1/32 inch beyond the crimp
American Wire Gauge
Both the crimping tool and size of cable to be used
Multimeter set to AC volts
Yes by adjusting the pins
Horizontal
20
The bleed valve opens and the ram retracts
Measure the millivolt drop across the connection with a millivolt meter
Released from the rear and extracted from the rear
Conductivity
- An HT lead is
a) single core screened
b) multi core screened
c) single core unscreened
c) single core unscreened
- A 14 gauge cable when compared to an 18 gauge cable has
a) lower current rating
b) higher current rating
c) the same current rating
b) higher current rating
3 An interconnect cable has what insulation?
a) thinner than airframe cable
b) thicker than airframe cable
c) same thickness as airframe cable
a) thinner than airframe cable
- Max temperature of tin coated copper cable?
a) 135oC
b) 200oC
c) 260oC
a) 135oC
- Plug pins are numbered
a) from the outside in - clockwise b) from the inside out - anticlockwise c) from the inside out - clockwise
c) from the inside out - clockwise
- Equipment wire
a) is flexible and suitable for soldering
b) can be used for interconnect wiring
c) has thicker insulation than interconnect wire
a) is flexible and suitable for soldering
- In the wiring code shown, what does the number 6 (4th number from the left) represent?
1EF6B22 NMS V
a) Cable size b) Cable number c) Circuit function
b) Cable number
- An aluminium oxide layer on a conductor will do what when the temperature is increased?
a) Become thicker
b) Become thinner
c) Remain the same
a) Become thicker
- What is a coaxial cable?
a) Two or more conductors b) A twisted pair of conductors c) A single shielded cable
c) A single shielded cable
- ‘X’ on a cable indicates
a) emergency power
b) control system
c) AC power
c) AC power
- What must you be careful with a hot stamped cable?
a) Wet arc tracking
b) Corrosion
c) Peeling of the insulation
a) Wet arc tracking
- What is the effect of aluminium oxide on aluminium electrical cable?
a) Provides strength b) Reduces resistance c) Insulates
c) Insulates
- Composition of silver solder is
a) tin and lead b) tin, lead and silver c) tin, lead, silver and antimony
c) tin, lead, silver and antimony
- What amperage is an 18 swg cable?
a) 10 amp
b) 5 amp
c) 1 amp
a) 10 amp
- A co-axial cable is better than a normal cable because
a) there is an electrostatic field around it which helps to reduce the electromagnetic field b) weight for weight it can carry more signal c) it has less resistance
a) there is an electrostatic field around it which helps to reduce the electromagnetic field
- What is the danger if a silver coated connector comes into contact with glycol de icing fluid
a) Fire hazard b) Corrosion c) Wet arc tracking
a) Fire hazard
- The conductor in tersil cable is
a) tinned copper b) nickel plated copper c) stainless steel
b) nickel plated copper
- A cable is marked NYVIN 22. The 22 represents the
a) current rating
b) current/weight ratio
c) cross sectional area
c) cross sectional area
- Copper is an inferior conductor to aluminium when comparing
a) weight for weight
b) CSA with CSA
c) load for load
weight for weight
Aluminium is better than copper when you compare weight to weight
- Silver plated copper wire has a maximum working temp ofa) 260 oC
b) 200 oC
c) 300 oC
b) 200 oC
Nickel - 260
Silver - 200
Tin 135
- For an electrical cable to be fireproof it must be able to stand 1100 deg C for
a) 10 mins b) 15 mins c) 20 mins
b) 15 mins
- Oxide on exposed silver plated wires is
a) non corrosive
b) an insulator
c) a conductor
b) an insulator
- In a front release connector the pin will be
a) released from the front and extracted from the rear
b) released from rear and extracted from the front
c) released from the front and extracted from the front
a) released from the front and extracted from the rear
- What cable would you use where temperatures are going to exceed 200 degrees C?
a) Aluminium
b) Silver plated
c) Nickel plated
c) Nickel plated
- A dry joint in soldering is caused by
a) flux not used
b) components not hot enough
c) wrong solder used
b) components not hot enough
- The type of flux to be used When soft soldering on aircraft is
a) active
b) non-active
c) either active or non-active
b) non-active
- To carry out an insulation test on a wire rated at 115 volts you would use
a) a 500 volt meggar
b) a 250 volt meggar
c) a 115 volt meggar
b) a 250 volt meggar
- A wire clamped vertically at one end and horizontally at the other end should have a bend radius of no less than
a) 10 times the diameter of the wire
b) 3 times the diameter of the wire
c) 5 times the diameter of the wire
b) 3 times the diameter of the wire
- A dry joint when soldering is caused by
a) too much flux
b) too little heat
c) too large an iron
b) too little heat
- With a rear release connecter, the pin will be
a) released from the front and extracted from the rear
b) released from the rear and extracted from the rear
c) released from the rear and extracted from the front
b) released from the rear and extracted from the rear
- The maximum operating temperature for a nickel plated copper or aluminium connector is
a) 135oC
b) 200 oC
c) 260 oC
c) 260 oC
- What gauge of pin would a yellow plastic insert / extract tool be used on?
a) 12 - 10
b) 22 - 18
c) 16 - 14
a) 12 - 10
- Can the insulation grip be adjusted on a PIDG crimp tool?
a) No
b) Yes by turning a knob
c) Yes by adjusting the pins
c) Yes by adjusting the pins
- What gauge of pin would a red plastic insert / extract tool be used on?
a) 12 - 10
b) 22 - 18
c) 16 - 14
b) 22 - 18
- What cable would you use where temperatures are going to exceed 200oC?
a) Tinned copper or aluminium
b) Silver plated copper or aluminium
c) Nickel plated copper or aluminium
c) Nickel plated copper or aluminium
36.The maximum value of bonding of a secondary structure is
a) 1 kilohm
b) 1 megohm
c) 1 ohm
c) 1 ohm
- What gauge of pin would a blue plastic insert / extract tool be used on?
a) 12 - 10
b) 22 - 18
c) 16 – 14
c) 16 – 14
- The insulation resistance for wiring in undercarriage wheelwells should normally be not less than
a) 10 megohms
b) 5 megohms
c) 2 megohms
c) 2 megohms
- Circuit tests on aircraft should be carried out in the following order
a) continuity, bonding, functional, insulation
b) functional, bonding, continuity, insulation
c) bonding, continuity, insulation, functional
c) bonding, continuity, insulation, functional
- After the normal function test of an individual circuit has been completed and the circuit switched off
a) a second function test must be carried out to verify the first
b) the fuse should be removed and the circuit again switched on to check the isolation of the circuit concerned
c) a duplicate check must be carried out in accordance with AWN 3
b) the fuse should be removed and the circuit again switched on to check the isolation of the circuit concerned
- A 250 volt megger should not be used
a) in fuel tanks
b) on electronic equipment
c) on radio aerials
b) on electronic equipment
- If the leads of a megger are held apart
a) the spring will return the needle to the zero stop
b) if the handle was turned the metre would read infinity
c) the spring will return the needle to infinity
b) if the handle was turned the metre would read infinity
- What causes knuckling on older type electrical cables?
a) Excessive pull through forces
b) Over-temperature soldering
c) Applying cable ties too tightly
a) Excessive pull through forces
- To find a high resistance or open circuit, carry out
a) a bonding check
b) a milli-volt drop test
c) a continuity check
c) a continuity check
- The maximum bonding resistance on an aircraft primary structure should be
a) 0.001 ohms
b) 0.01 ohms
c) 0.05 ohms
c) 0.05 ohms
- One megohm is equal to
a) 1,000 ohms
b) 100,000 ohms
c) 1,000,000 ohms
c) 1,000,000 ohms
- Before effecting a crimp, the bare ends of a cable should be
a) twisted lightly in the direction of the lay
b) straightened out
c) tightly twisted
a) twisted lightly in the direction of the lay
- The leads of a bonding tester
a) have critical lengths and the resistance of the leads is accounted for
b) are supplied in 60 foot and 6 foot lengths but can be varied due to wear
c) are interchangeable, one 60 foot long having two prongs and a 6 foot one with a single prong
a) have critical lengths and the resistance of the leads is accounted for
- The number of the dots impressed on the insulation of the pre-insulated connectors during crimping indicates that
a) the crimp is properly formed
b) the correct tool was used to effect the connection
c) the correct connector has been used
b) the correct tool was used to effect the connection
- The pressure of the insulation crimp jaws on the PIDG crimping tool can be changed by
a) varying the torque applied to the handles
b) changing the position of the pins
c) using different coloured crimping pliers and terminations
b) changing the position of the pins
- When referring to fuses, HRC means
a) hot running capacity
b) high running current
c) high rupture capacity
c) high rupture capacity
- High temperature solder is used where the operating temperature is high. It is an alloy of
a) lead / copper / antimony
b) tin / zinc / antimony / silver
c) tin / lead / antimony / silver
c) tin / lead / antimony / silver
- A flux is used in soldering to
a) etch the metal surface for more adhesion
b) dissolve oxides
c) prevent solder spikes
b) dissolve oxides
- The test equipment normally used to carry out a continuity test on an electrical cable is
a) a high tension circuit tester
b) a low reading ohmmeter
c) an ammeter
b) a low reading ohmmeter
- If all three prongs on a bonding tester were shorted together, the metre would read
a) zero
b) FSD
c) off-scale high
a) zero
- A hole is placed in the lowest point of electrical cable conduit
a) to allow for pull-through of the cables
b) to allow for drainage of moisture
c) to secure the conduit to a piece of aircraft structure
b) to allow for drainage of moisture
- The soldering method where molten solder is pumped from the bottom of a bath through a slot so that a stationary wave of solder appears on the surface is known as the
a) standing wave bath method
b) stationary wave method
c) rotary bath method
a) standing wave bath method
- A fire resistant cable is proof tested by exposure to a standard fire for
a) 5 minutes
b) 15 minutes
c) 30 minutes
a) 5 minutes
- When making a small soldered electrical connection, using flux-cored solder
a) the soldering iron should be loaded with solder and then applied to the connection
b) the connection should be heated first and then solder applied
c) the soldering iron and solder should be applied simultaneously to the connection
c) the soldering iron and solder should be applied simultaneously to the connection
- Silver solder melts within the range
a) 200° C - 400° C
b) 400° C - 550° C
c) 600° C - 850° C
c) 600° C - 850° C
- An open circuit on an ohmmeter would be indicated by a reading of
a) infinite resistance
b) zero resistance
c) a negative resistance
a) infinite resistance
- The leads of an ohmmeter should be replaced if their resistance is greater than
a) 0.05 ohms
b) 0.5 ohms
c) 1 ohm
c) 1 ohm