Aircraft Electrical Systems - Circuit Symbols

yipufuji's version from 2017-08-02 14:46

Section 1

Question Answer
Zener Diode - Allows current flow in one direction, but also can flow in the reverse direction when above breakdown voltage
XOR Gate - Outputs 1 when inputs are different. (Exclusive OR)
Not Connected Wires - Wires are not connected
onnected Wires - Connected crossing
Wattmeter - Measures electric power
Voltmeter - Measures voltage. Has very high resistance. Connected in parallel.
Variable Resistor / Rheostat (IEEE) - Adjustable resistor - Has 2 connections ~ One goes to one end of the track and the other goes directly to the wiper to vary the level of the source
Variable Capacitor - Adjustable capacitance
SPST Toggle Switch - Disconnects current when open
SPDT Toggle Switch - Selects between two connections
AC Voltage Source
Earth Ground - Used for zero potential reference & electrical shock protection.
Ammeter - Measures electric current. Has near zero resistance. Connected serially.
AND Gate - Outputs 1 when both inputs are 1.
Battery - Generates constant voltage
Battery Cell - Generates Constant voltage
Capacitor - Used to store electric charge. Acts as short circuit with AC and open circuit with DC.
Current Source - Generates constant current
Chassis Ground - Connected to the chassis of the circuit
Generator - Electrical voltage is generated by mechanical rotation of the generator
Fuse - Breaks when current goes above threshold. Protects circuit from high currents.
Diode - Allows current flow in one direction
Inductor - Coil / solenoid that generates magnetic field
Variable Inductor
Lamp / light bulb - generates light when current flows through
NOR Gate - Outputs 0 when any input is 1. (NOT + OR)
Ohmeter - Measures resistance
OR Gate - Outputs 1 when any input is 1
Potentiometer - Adjustable resistor - has 3 connections ~ The two ends of the track are wired across a voltage source and the third connection goes to the wiper to select a specific voltage from that source
Push Button Switch ( Normally Open ) - Momentary switch
Push Button Switch ( Normally Closed ) - momentary Switch
Resistor - Reduces current flow
Thermistor - Thermal resistor - change resistance when temperature changes
Transformer - Changes AC voltage from high to low, or low to high
Voltage Source - Generates constant voltage
NAND Gate - Outputs 0 when both inputs are 1. (NOT + AND)
Motor - Electric motor
Lamp / Light bulb - Generates light when current flows
Lamp / Light bulb - Generates light when current flows

Section 2