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ELECTRIC MOTOR CONTROLS
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2 [/ d: l" q% Q, ]Once the proper motor is selected, understanding the many various control devices available and 3 l! C& w- x8 Z1 M7 a
their uses and limitations becomes an important part related to reliable operation and protection of
* m2 `5 H. `3 C2 y1 [2 Sthe motor and the personnel using the motor. G6 X* w: R1 s9 g y
% F. w0 H. G9 M+ I6 u, U2 Z* [# JMotor Control Topics
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1 G4 ~0 p( U7 ]: Q8 ^0 [There are four major motor control topics or categories to consider. Each of these has several
* p$ f. h' p" F; p& M* F* tsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
5 d+ a2 t" T% N7 xcontrol equipment can accomplish multiple functions from each of the topics or categories.
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! a: W) p$ |: M5 p4 {$ VThe four categories include: 8 P2 M9 ]# T9 r+ I2 H' A6 \
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1) Starting the Motor
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Disconnecting Means
( W9 J$ A% C. i) J# zAcross the Line Starting
' b$ [; x- N! k* VReduced Voltage Starting / ^' e/ E; R% j
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2) Motor Protection ) T0 n K9 @& f; `6 k U. w& W, k
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Overcurrent Protection
& W ^1 p: Y. B4 j$ S6 EOverload Protection 5 X* `% k/ t6 v0 C
Other Protection (voltage, phase, etc) ( h. b2 P1 A& q+ c/ }/ V
Environment
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3) Stopping the Motor 4 h) ?; \3 g+ H4 S- H5 U0 A
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Coasting
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Mechanical Braking
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$ c. D& l3 v# K7 u% u3 d* q) s4) Motor Operational Control : P- m# b6 p! J4 L
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Speed Control , s3 j5 [# h+ j
Reversing
, w B' Y! Y* S' ?: P; qJogging
8 S* k! p. E2 Z2 ~% M$ FSequence Control |
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