Troubleshooting electrical and wiring faults
Wiring diagrams and standard practices, safe measurement, voltage drop, insulation tests, half-split isolation, connectors, chafing and EWIS, circuit breakers and arcs, repairs, bonding and dispatch
What you will be able to do
- ✓ Use wiring diagram, schematic and standard practices manuals to plan a fault isolation and predict healthy readings.
- ✓ Measure safely with multimeters and insulation testers, and interpret continuity, resistance and voltage drop against published limits.
- ✓ Locate open, short, high-resistance and intermittent faults with half-split logic, wiggle tests and time domain reflectometry.
- ✓ Recognise connector, pin and chafing defects and apply the EWIS design, EZAP inspection and training requirements in the US and European rules.
- ✓ Explain how circuit breakers and arcs behave, apply the reset rule, and use the official findings on Boeing 737-300 G-LGTI.
- ✓ Repair wiring within limits, verify bonds and repairs by measurement, and decide when MEL relief can and cannot be used.
Course content
Session 1 · Wiring faults and the troubleshooting method
1.1
- Why wiring faults are different · free preview
- The documents: diagrams, schematics and standard practices
- A method for troubleshooting
- Worked example: reading the diagram to find an open ground
Session 2 · Measuring safely: meters, continuity and voltage drop
1.2
- Meters and measuring safely
- Continuity and resistance: what the ohmmeter tells you
- Voltage drop: testing the circuit under load
- Worked example: a voltage-drop budget along a run
Session 3 · Opens, shorts and insulation: finding the fault
1.3
- Open, short and high-resistance faults: reading the symptoms
- Insulation resistance testing and its risks
- Locating the fault: half-split, wiggle tests and TDR
- Worked example: a half-split fault isolation
Session 4 · Connectors, chafing and EWIS
1.4
- Connectors and pins: fretting, corrosion and retention
- Chafing, routing and separation
- EWIS rules: design, zonal analysis and training
- From the investigation file: Boeing 737-300 G-LGTI
Session 5 · Circuit breakers, arcs and the reset rule
1.5
- Circuit breakers and fuses: what they protect
- Arc faults: when the breaker stays in
- The reset rule
- Worked example: a circuit breaker trip decision
Session 6 · Repairs, bonding, testing and dispatch
1.6
- Splices and repair limits
- Bonding and grounding
- After the repair: tests, records and the MEL
- Worked example: a bonding resistance check against the limit
Who this course is for
Course content © Aerospace Garage Limited. All rights reserved.