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ELECTRIC MOTOR CONTROLS
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Once the proper motor is selected, understanding the many various control devices available and . \6 U* H+ b9 ^# L% t
their uses and limitations becomes an important part related to reliable operation and protection of + r$ c$ l' t3 d. p3 W9 ^7 H$ O8 q* a
the motor and the personnel using the motor.
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Motor Control Topics
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3 A% f/ j/ s+ {- Q8 H& U6 Y: V- B" DThere are four major motor control topics or categories to consider. Each of these has several
+ e, Q& L+ a5 ^) ]. l& q( _% usubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
. y+ Z; W; @2 n6 `4 W7 _" Hcontrol equipment can accomplish multiple functions from each of the topics or categories. % m& E% h( M6 I. w1 b [
' Y' X& t; [5 V' I: }7 B" D) [The four categories include: * R8 [0 x3 E8 B
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1) Starting the Motor
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3 l1 [ A0 x" x% U+ C) X' l% `* V& oDisconnecting Means
& W3 ^# X% Q/ t5 ^7 S- F' ]Across the Line Starting
6 v; b7 Y: N( S) VReduced Voltage Starting * r" F+ _, D! `! E( }$ G: g
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2) Motor Protection
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; g" v3 q% e8 }* j+ M3 F" N* Z; m6 eOvercurrent Protection
' j# W& X9 P& p( U) w- yOverload Protection
0 P. P) U+ Q6 P; {* v/ OOther Protection (voltage, phase, etc)
# `( J( m2 ]3 D% Q+ wEnvironment
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' N) |. j& T8 _# @8 W" P8 U9 m9 Z3) Stopping the Motor ' H# T; M0 R* }) i* W" h
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Coasting
# T" j. Z n3 m5 X Z/ M2 \Electrical Braking
: h. @* @! M1 D) eMechanical Braking
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2 S# s. ~# x' G8 }+ Z# _8 u. J0 j4) Motor Operational Control . d- ]+ V/ p1 H( ^
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Speed Control
, F0 T1 S& L' N% D1 FReversing
: E! Q% }7 O6 v$ m2 I. yJogging * S# W8 y6 J9 s$ X, o
Sequence Control |
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