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ConnectionsMechanical
Wiringterminal
Ground
Notconnected
Notconnected Connected
Miscellaneous
Annunciator
Hornsiren
Half wave
Battery
Full wave
Meter
Fusepower orcontrol
Indicatetype byletter
Metershunt
Thermo-couple
Bell Buzzer
Transformers
DC motors
Capacitors
Wiring
AC motors
Auto
Armature
Current
RES RES RH
VM
AM
AC
DCDC
AC
Resistors
Supplementary contact
Terms
SPST—Single pole single throw
SPDT—Single pole double throw
DPST—Double pole single throw
DPDT—Double pole double throw
N.O.—Normallyopen
N.C.—Normally closed
SPST.N.C.SPST.N.O. SPDT
Heatingelement
Adj. byfixed taps
Rheostat.pot. oradj. tap
Fixed
Adj.
H
Singlebreak
DPST, 2 N.O. DPST, 2 N.C. DPDT
Singlebreak
Doublebreak
Singlebreak
Doublebreak
Singlebreak
Doublebreak
Doublebreak
Singlebreak
Doublebreak
Singlebreak
Doublebreak
PowerControlHomeUndergrnd.Concealed in floor Number ofconductors (4)Exposed
* No. of arrows = no of circuits
Ironcore
Shuntfield
Seriesfield
Comm orcompens.
field
Aircore
Dualvoltage
Singlephase
3 phasesq. cage
2 phase4 wire
Woundrotor
Mechanical interlock
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ELECTRICAL SYMBOLS