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ELECTRIC MOTOR CONTROLS {# s6 H2 {2 j5 {' b- ~6 x8 n
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Once the proper motor is selected, understanding the many various control devices available and * v3 ]) m4 s; d" A4 P: l1 B
their uses and limitations becomes an important part related to reliable operation and protection of
" }# {1 ]8 r* U! [5 jthe motor and the personnel using the motor. % r5 ]; H; K& r7 K
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Motor Control Topics : O. z- i5 A2 W2 @* j4 F
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There are four major motor control topics or categories to consider. Each of these has several 7 q& K. M+ d5 R9 E, S3 L1 U
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
* } [0 S3 l9 R" Ncontrol equipment can accomplish multiple functions from each of the topics or categories.
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& b* Z% \ R0 {The four categories include: / S& Z' ]5 I8 P0 j& n6 A$ L
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1) Starting the Motor & R3 G2 l$ q) u$ n% D; h. Q' v
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Disconnecting Means ! k/ B) }' Z5 R: j
Across the Line Starting
; @# {7 f1 u4 {# M2 ?6 H. sReduced Voltage Starting
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2) Motor Protection
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, U/ A% c$ K0 _8 LOvercurrent Protection
4 _- U0 X$ b$ ~& m H! S, FOverload Protection
9 K( L; e: E. d# J0 NOther Protection (voltage, phase, etc)
$ L, |7 d0 x) Z. A& QEnvironment 3 W3 \9 k) o9 b4 `0 ?8 m |
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3 [7 }9 H/ C O) l+ I/ ?3) Stopping the Motor % [/ A+ b2 f; {$ o. j' m0 F
5 Y# o# i7 m) WCoasting , x4 B3 y% y7 x3 H/ o
Electrical Braking 3 a3 u/ |$ B! }6 {+ L
Mechanical Braking ! z& b1 c: A' V0 p V8 N, Z
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0 }: y( Q5 y+ r! x4) Motor Operational Control
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Speed Control
8 z, U; x+ z# U) ~8 b9 P( HReversing 9 ]: Y9 w' R4 W. Q0 X) O" D
Jogging
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