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ELECTRIC MOTOR CONTROLS
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# _2 F5 m4 g3 u0 ~4 T! \Once the proper motor is selected, understanding the many various control devices available and
. T9 X6 o% D) _* T' R" Y4 @% `their uses and limitations becomes an important part related to reliable operation and protection of 0 {8 o3 P* }- ~; d' B. f
the motor and the personnel using the motor.
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; Y* w# C0 g( t- U* Z& h, KMotor Control Topics
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$ q+ P& x1 Z% h' @* ]5 ^There are four major motor control topics or categories to consider. Each of these has several
( h% f7 `/ q/ v0 j" isubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
2 t" J! w7 ?4 T& |0 T) v$ Tcontrol equipment can accomplish multiple functions from each of the topics or categories.
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The four categories include:
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7 C( v, d; r% m9 H/ a S, z5 a+ T) ?1) Starting the Motor 8 `2 t/ }" | N! P% o, ~
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Disconnecting Means
& B P% j3 Q/ i) bAcross the Line Starting
/ Q3 a$ G$ r* i# u- j+ \% hReduced Voltage Starting % c: @$ o- Z1 V$ i$ i3 g
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. v d- r& N: O# e2) Motor Protection / L+ n' q2 b- O, K0 G7 m/ s3 g
5 d% O8 b$ u, \9 |$ i# a0 u3 _8 wOvercurrent Protection 5 D1 ~1 L2 @% B
Overload Protection
/ f+ V( U( l" I9 h% w5 _( Z: _4 aOther Protection (voltage, phase, etc) ( b. n0 O; p8 T* X2 W
Environment
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- K- ^ }! ]; |3) Stopping the Motor
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Coasting # q! J9 D: V3 B0 y
Electrical Braking
N4 `: a+ I( o. {2 D; t1 w# B( N. {8 yMechanical Braking 4 l B0 E# [- u* E
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: D7 Y6 E2 o5 g) c" k( r, |4) Motor Operational Control 3 q, y! R- c# D1 e
" `% V+ {+ ^$ sSpeed Control
7 X. ] y, @: MReversing
& }0 u9 q( k- q1 l* B6 |Jogging
$ T; E& `. h& y, I( OSequence Control |
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