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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 4 u1 I9 S. q& l+ e1 C0 X
their uses and limitations becomes an important part related to reliable operation and protection of 6 p, x$ l R* V3 D
the motor and the personnel using the motor. 6 j3 b5 Q* H& i( x! `" L
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Motor Control Topics
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; i' \" |# k0 @% Y* MThere are four major motor control topics or categories to consider. Each of these has several 3 R! x8 }* C" ~$ Y
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
: a; {: ^2 U) V9 W, xcontrol equipment can accomplish multiple functions from each of the topics or categories. 0 O1 O. {5 b ]0 Q) Y3 @
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The four categories include: 7 g! J, {5 n/ p _" k1 L5 b
5 `, |6 K v* a% C1) Starting the Motor ' Z3 [8 v# g6 G( Y, T: W
# y7 Z. Q9 o/ W0 y1 f7 GDisconnecting Means % @% a K8 P4 c% G: R/ u, L P
Across the Line Starting / M% M. z! w0 y0 t& X0 n, v# c
Reduced Voltage Starting
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2) Motor Protection
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, B D1 ]) N4 o4 B% y" B% HOvercurrent Protection / l A8 i; Z9 r2 f& g
Overload Protection
: B) D* g# N" lOther Protection (voltage, phase, etc) 1 I3 O- m' A& w: g7 @$ w2 f6 o
Environment 4 P7 `+ t2 U, h" p1 I9 m
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3) Stopping the Motor
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! S( c( i7 o/ QCoasting
7 {* @0 q5 S' qElectrical Braking 0 E- w# D8 t8 Z. r8 r/ J
Mechanical Braking
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# D6 F% t' \* P# S& p4) Motor Operational Control 0 E) A# I8 E7 |9 i( E2 u0 o! R$ i
2 L5 n' ~, n. n! ?. LSpeed Control
9 |4 \ g% o+ A; i5 w6 R. XReversing ( v5 _4 M; r+ H5 a
Jogging
2 r8 h+ E, H: t& b: eSequence Control |
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