1. Aircraft Electrical Systems
Ted Spitzmiller
Aircraft Electrical Systems

2. Aircraft Electrical Systems
C-182T Electrical System
Aircraft Electrical Systems

3. Aircraft Electrical Systems
What is Electricity?
Flow of electrons from one atom to another - +
Aircraft Electrical Systems

4. Aircraft Electrical Systems
Like a bucket brigade
Aircraft Electrical Systems

5. Where do we get ‘positive 'attraction— from a battery…
Aircraft Electrical Systems

6. Putting some ‘resistance’ into the flow provides useful ‘work’
Aircraft Electrical Systems

7. ‘Current’ flows in the opposite direction to the electrons
Current (I) is the ‘amount’ of electrons flowing
Measured in Amps E
Voltage (E) is the ‘pressure’ of the electrons
Measured in Volts
Aircraft Electrical Systems

8. Aircraft Electrical Systems
Moving a coil in a magnet generates electricity to recharge the battery
Aircraft Electrical Systems

9. Aircraft Electrical Systems
Two types of ‘current’
Aircraft Electrical Systems

10. Aircraft Electrical Systems

11. Why is Electricity Dangerous
Minimum current a human can feel depends on current type (AC or DC) and freq.
1 mA of AC at 60 Hz (1/1000 of an amp)
5 mA for DC.
High current can cause tissue damage or fibrillation (cardiac arrest)
60 mA of AC (rms, 60 Hz)
300–500 mA of DC
AC at 120 V, 60 Hz is an especially dangerous because it usually exceeds the let-go threshold
Seriousness of the shock depends on current path through the body Ohms law E=IR
Aircraft Electrical Systems

12. Aircraft Electrical Systems
Quiz time
Electricity is the ‘flow’ of:
Protons
Neutrons
Electrons
Klingons
Aircraft Electrical Systems

13. Aircraft Electrical Systems
Question 2
In a DC circuit, the positive force used to make the current flow is often obtained from:
Wall socket
Battery
Alternator
Aircraft Electrical Systems

14. Aircraft Electrical Systems
Question 3
To keep a battery from depleting its ‘charge’, rapidly (and perhaps burning up) each item to be powered must provide some form of electrical:
Capacitance
Inductance
Resistance
Aircraft Electrical Systems

15. Aircraft Electrical Systems
Question 4
In a light bulb, the electrical resistance is in the form of the:
Socket
Filament
Glass enclosure
Aircraft Electrical Systems

16. Aircraft Electrical Systems
Question 5
In an electrical circuit, the amount of electron flow is measured by the:
Ammeter
Voltmeter
Loadmeter
Aircraft Electrical Systems

17. Aircraft Electrical Systems
Question 6
The pressure of the electron flow is measured by the:
Ammeter
Voltmeter
Dosimeter
Parkingmeter
Aircraft Electrical Systems

18. Aircraft Electrical Systems
Question 7
The purpose of a circuit breaker is to:
Sense current that may be too high for the circuit.
Interrupt the flow of electricity to the ‘load’
Protect the airplane’s electrical wiring
Prevent an electrical fire
Aircraft Electrical Systems

19. How much voltage does it take to kill a person?
15,000 volts
120 volts
While voltage may be a factor, as little as 30 ma of current can cause ventricular fibrillation..
Aircraft Electrical Systems

20. What is a ‘short circuit’?
A direct path from a ‘ground’ to the positive source of power
A abnormal low resistance connection
A possible destructive condition in an electrical circuit
All of the above
Aircraft Electrical Systems