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ELECTRIC MOTOR CONTROLS 8 j$ ]3 ~# u1 B6 E" b
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Once the proper motor is selected, understanding the many various control devices available and , D8 D/ k U1 @
their uses and limitations becomes an important part related to reliable operation and protection of
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* Z6 E1 d+ k* P* Q8 V2 pMotor Control Topics # \. o5 Q- F1 b/ k
2 m$ y3 H& [+ ?% h( v' t. \There are four major motor control topics or categories to consider. Each of these has several 3 |$ t) d# W7 z v
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
, q% O; ^! K1 u4 ~control equipment can accomplish multiple functions from each of the topics or categories.
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The four categories include: - B5 S; o( _8 A% B. P3 f w
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1) Starting the Motor
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Disconnecting Means
$ a* A, X, S. P4 H" f7 g9 fAcross the Line Starting 6 f4 U. F# O$ p0 e
Reduced Voltage Starting : D. ]5 w8 N2 Z! e8 c% G
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2) Motor Protection : I" [- K$ _5 G9 b
. r( {; z" i( V- ?Overcurrent Protection 9 g O; D$ p" y! ]. @
Overload Protection
2 B5 x- d) G7 a4 F3 @Other Protection (voltage, phase, etc) $ ^. C2 W& N% L9 v6 M+ e
Environment
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. r; K& R9 p3 d. Y9 Q8 |3) Stopping the Motor 7 o8 B. E9 V( h9 h& w4 s
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Coasting
9 [% b1 t1 I4 Z9 zElectrical Braking
1 o. f2 k: v( C; \0 i% K! WMechanical Braking
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9 v$ V v8 q* y# `4) Motor Operational Control # U9 V( y1 H: }. u1 e |
6 [2 A! x; ~1 [5 Z1 x E$ _Speed Control
7 x% s% U; _; V: W$ jReversing 1 L; K' n" h9 y8 `! I9 ^' j: W- s1 O
Jogging ' D6 h: y/ M8 h8 H$ y# ~/ A
Sequence Control |
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