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ELECTRIC MOTOR CONTROLS
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% T3 c8 f% y1 I8 u% L5 OOnce the proper motor is selected, understanding the many various control devices available and ; a2 l0 p, T& U9 n" M
their uses and limitations becomes an important part related to reliable operation and protection of ( U/ W7 P1 W. ^: T
the motor and the personnel using the motor.
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Motor Control Topics
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/ z' e" r. ]) K4 s# C: B vThere are four major motor control topics or categories to consider. Each of these has several 7 P9 l9 J. Z# m# k
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor 9 Q; V1 g+ d j9 O9 K
control equipment can accomplish multiple functions from each of the topics or categories. 2 L9 G8 J6 x! i* b
, B' h1 l- i# f1 F- wThe four categories include:
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$ V% C- X9 @+ A: C1) Starting the Motor 9 Z$ f- k1 ~4 K' v
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Disconnecting Means - f: j) u+ i/ S& s5 U
Across the Line Starting
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2) Motor Protection 0 U- ?" k. g5 Q% m! I3 J0 [+ [
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Overcurrent Protection $ v3 T4 d1 i2 k3 T; H; u# n4 c
Overload Protection
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Environment & h9 k& [- S z2 h: u* n, A
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3) Stopping the Motor ; K3 {0 Q9 e+ c2 S: |' A
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Coasting ( h; e" H7 V& J% l* ^4 u
Electrical Braking
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; W' D& ]) }- l3 e4) Motor Operational Control
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0 f& Y2 |/ h8 v; y+ \Speed Control 7 b# N8 T5 @7 S7 V; R
Reversing : ~; k! [& @1 v+ F1 R) s8 Y; w
Jogging " V6 v4 f5 q, H7 ~
Sequence Control |
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