Basic Electrical Theory
ELECTRICAL SYMBOLS
ELECTRICAL SYMBOLS
To read and interpret electrical system diagrams and schematics, one must be
thoroughly familiar with the many symbols used. Once these symbols are
mastered, most electrical diagrams and schematics will be understood with
relative ease.
EO 1.14
Given a standard electrical symbol, IDENTIFY the component that the
symbol represents. The symbols will be for the following components:
a.
Resistor
m.
Fuse
b.
Capacitor
n.
Junction
c.
Inductor
o.
AC voltage source
d.
Relay
p.
Voltmeter
e.
Contacts
q.
Ammeter
f.
Breaker
r.
Wattmeter
g.
Switch
s.
Relay operated contacts
h.
Transistor
t.
Potential transformer
i.
Rheostat
u.
Current transformer
j.
Diode
v.
Wye (Y) connection
k.
Ground connections
w.
Delta (D) connection
l.
Vacuum tube
x.
Light bulb
y.
Battery
Symbols
The symbols for the various electrical components that will appear on electrical diagrams and
schematics are shown in Figure 30.
Rev. 0
Page 45
ES-01
