The document provides symbols and diagrams for various industrial electrical components. It includes symbols for circuit breakers, switches, relays, meters, transformers, motors, wiring diagrams, semiconductors and other devices. The symbols are used in electrical schematics to represent the components.

1. INDUSTRIAL ELECTRICAL SYMBOLS . . .
CIRCUIT BREAKER
DISCONNECT CIRCUIT CIRCUIT BREAKER CIRCUIT BREAKER W/ THERMAL AND
INTERRUPTER WITH THERMAL OL WITH MAGNETIC OL MAGNETIC OL
LIMIT SWITCHES PRESSURE AND LIQUID TEMPERATURE-
FOOT VACUUM LEVEL ACTUATED FLOW SWITCH
NORMALLY NORMALLY SWITCHES (AIR, WATER, ETC.)
OPEN CLOSED SWITCHES SWITCH SWITCH
NO NO NO NO NO
HELD HELD
CLOSED OPEN NC NC NC NC NC
SYMBOLS FOR STATIC SWITCHING CONTROL DEVICES
SPEED (PLUGGING) ANTI-PLUG
STATIC SWITCHING CONTROL IS A METHOD OF SWITCHING
ELECTRICAL CIRCUITS WITHOUT USE OF CONTACTS,
F F F PRIMARILY BY SOLID-STATE DEVICES. USE SYMBOLS
SHOWN IN TABLE AND ENCLOSE THEM IN A DIAMOND.
INPUT COIL OUTPUT NO LIMIT SWITCH NO LIMIT SWITCH NC
R R
SELECTOR
TWO-POSITION THREE-POSITION TWO-POSITION SELECTOR PUSHBUTTON
SELECTOR POSITION
J K K
J K J L J K L A B
A B CONTACTS
A1 A1 1 2 BUTTON BUTTON
A1 X A1 X FREE DEPRESSED FREE DEPRESSED
A2 A2 3 4
A2 X A2 X 1 2 X
3 4 X X X
X-CONTACT CLOSED X-CONTACT CLOSED X - CONTACT CLOSED
PUSHBUTTONS
MOMENTARY CONTACT MAINTAINED CONTACT ILLUMINATED
SINGLE DOUBLE MUSHROOM WOBBLE TWO ONE
CIRCUIT CIRCUIT HEAD STICK SINGLE DOUBLE
CIRCUIT CIRCUIT R
NO AND NC
NO
NC
©1999 American Technical Publishers, Inc.

2. . . . INDUSTRIAL ELECTRICAL SYMBOLS . . .
CONTACTS OVERLOAD RELAYS
TIMED CONTACTS - CONTACT ACTION THERMAL MAGNETIC
INSTANT OPERATING
RETARDED AFTER COIL IS:
WITH BLOWOUT WITHOUT BLOWOUT ENERGIZED DE-ENERGIZED
NO NC NO NC NOTC NCTO NOTO NCTC
SUPPLEMENTARY CONTACT SYMBOLS
SPST NO SPST NC SPDT TERMS
SINGLE DOUBLE SINGLE DOUBLE SINGLE DOUBLE
BREAK BREAK BREAK BREAK BREAK BREAK SPST
SINGLE-POLE,
SINGLE-THROW
SPDT
SINGLE-POLE,
DOUBLE-THROW
DPST
DOUBLE-POLE,
DPST, 2NO DPST, 2NC DPDT SINGLE-THROW
SINGLE DOUBLE SINGLE DOUBLE SINGLE DOUBLE DPDT
BREAK BREAK BREAK BREAK BREAK BREAK DOUBLE-POLE,
DOUBLE-THROW
NO
NORMALLY OPEN
NC
NORMALLY CLOSED
METER (INSTRUMENT) PILOT LIGHTS
INDICATE TO INDICATE FUNCTION OF METER OR INSTRUMENT, INDICATE COLOR BY LETTER
TYPE BY PLACE SPECIFIED LETTER OR LETTERS WITHIN SYMBOL.
LETTER NON PUSH-TO-TEST PUSH-TO-TEST
AM or A AMMETER VA VOLTMETER
V AH AMPERE HOUR VAR VARMETER
A MICROAMMETER VARH VARHOUR METER A R
mA MILLAMMETER W WATTMETER
AM
PF POWER FACTOR WH WATTHOUR METER
V VOLTMETER
INDUCTORS COILS
IRON CORE DUAL-VOLTAGE MAGNET COILS
BLOWOUT
COIL
HIGH-VOLTAGE LOW-VOLTAGE
LINK LINKS
1 2 3 4 1 2 3 4
AIR CORE
©1999 American Technical Publishers, Inc.

3. . . . INDUSTRIAL ELECTRICAL SYMBOLS . . .
TRANSFORMERS
AUTO AIR CORE CURRENT CONTROL TRANSFORMER AUTOTRANSFORMER
FOR REDUCED-
VOLTAGE STARTING
SINGLE- DUAL-
VOLTAGE VOLTAGE % %
50 50
H3 H2
H1 H2 H1 H4 65 65
80 80
100 100
X2 X1 X2 X1 0 0
AC MOTORS
SINGLE- SEPARATE PHASE, SEPARATE WINDING, CONSTANT-TORQUE,
THREE-PHASE
PHASE TWO-SPEED TWO-SPEED TWO-SPEED
T1 T2 HIGH COM LOW T1 T2 T3 T1 T11
T4
T1 T2 T3
T3 T1
T3 T2 T13 T12 T5 T2 T6
VARIABLE-TORQUE, CONSTANT- WYE/DELTA, WYE-CONNECTED, PART WINDING,
TWO-SPEED HORSEPOWER, REDUCED- REDUCED-VOLTAGE
TWO-SPEED VOLTAGE
T4 T4
T1 T2 T3 T7 T8 T9
T5
T6 T1
T1
T3 T1
T3
T3 T4
T4 T6
T2 T6 T5 T6
T5 T2 T5 T2
DC MOTORS WIRING CONNECTIONS
COMM OR NOT WIRING MECHANICAL
SHUNT SERIES COMPENS POWER
ARMATURE FIELD FIELD CONNECTED TERMINAL
FIELD
ARM
SHOW 4 SHOW 3 SHOW 2
LOOPS LOOPS LOOPS MECHANICAL
CONNECTED CONTROL GROUND INTERLOCK
CONTROL AND POWER CONNECTIONS-600 V OR LESS ACROSS-THE-LINE STARTERS
1 2 , 4-WIRE 3
L1, L3 PHASE 1
LINE MARKINGS L1, L2 L1, L2, L3
L2, L4 PHASE 2
L1 IS ALWAYS
GROUND WHEN USED UNGROUNDED L2
MOTOR RUNNING 1 ELEMENT L1
OVERCURRENT 2 ELEMENT L1, L4
UNITS IN 3 ELEMENT L1, L2, L3
CONTROL CIRCUIT L1, L2 L1, L3 L1, L2
CONNECTED TO
FOR REVERSING L1, L3 L1, L3
INTERCHANGE LINES
©1999 American Technical Publishers, Inc.

4. . . . INDUSTRIAL ELECTRICAL SYMBOLS
RESISTORS CAPACITORS
ADJUSTABLE BY RHEOSTAT, POT, OR
FIXED FIXED ADJUSTABLE POLARIZED
FIXED TAPS ADJUSTABLE TAP
RES
+ _
H RES
RES
HEATING ELEMENT
FUSE BELL BUZZER HORN, HALF-WAVE FULL-WAVE
SIREN, ETC. RECTIFIER RECTIFIER
POWER OR
CONTROL AC
+ _
DC DC
AC
BATTERY IGNITRON SEMICONDUCTORS . . .
THERMOCOUPLE TUBE
TUNNEL UNIDIRECTIONAL
DIODE BREAKDOWN
DIODE
DOT IN TUBE (ZENER) DIODE
DENOTES GAS
+ _
. . . SEMICONDUCTORS . . .
BIDIRECTIONAL TRIAC SILICON PROGRAMMABLE
PHOTOSENSITIVE
BREAKDOWN (BIDIRECTIONAL CONTROLLED UNIT - JUNCTION
CELL
DIODE TRIODE THYRISTOR) RECTIFIER TRANSISTOR (PUT)
. . . SEMICONDUCTORS
TRANSISTOR UNIJUNCTION TRANSISTOR
PNP BASE NPN BASE P BASE N BASE
(C) (C)
(B2) (B2)
(E) (E)
(B) (B)
(E) (E) (B1) (B1)
©1999 American Technical Publishers, Inc.