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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
1 Q2 T' O) g: `; ?( n) Rtheir uses and limitations becomes an important part related to reliable operation and protection of
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+ a4 l; T' p' y* U) r! C: n0 AMotor Control Topics ; n$ F6 a2 [, t3 F4 i
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There are four major motor control topics or categories to consider. Each of these has several 2 m( l% b# a6 K4 L! u) U
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor " I. d+ r H$ l
control equipment can accomplish multiple functions from each of the topics or categories. ! z( z1 i# R, `) J. t
; V0 n; Y' c1 y" I) I" y2 XThe four categories include: ( u5 L$ W+ o. }: S( S$ P
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1) Starting the Motor ' H. R8 p" c; Z) j
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Disconnecting Means
/ { w! o) R7 OAcross the Line Starting
' N7 N' i& R0 j; t BReduced Voltage Starting ( `: Y6 |5 h9 k7 b% v
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% P& E# _2 A# g, x2) Motor Protection / ]2 P. `6 D7 l8 R# d% ?" R$ T
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Overcurrent Protection
: j5 P6 R0 @1 ] ?- q+ V' vOverload Protection . R( e6 P, F1 q; {9 ?2 G
Other Protection (voltage, phase, etc) ) r6 r" X- c! A' Q
Environment
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3) Stopping the Motor $ i5 s: g' c) S G' h$ g6 D0 o2 K
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Coasting
( N. d* t. [9 S6 QElectrical Braking ; T/ P# @* Q- B5 O; ?: s6 {
Mechanical Braking
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4) Motor Operational Control
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Speed Control
1 w6 l; |, r$ T5 S; oReversing 7 t( q+ u) X8 \# b% ^5 `8 u
Jogging : i' v) w# r r3 p
Sequence Control |
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