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ELECTRIC MOTOR CONTROLS # j5 ^ ], Z: D2 T6 V' |8 T
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Once the proper motor is selected, understanding the many various control devices available and
/ `& N/ c0 @& \, }) G; j7 ]: ptheir uses and limitations becomes an important part related to reliable operation and protection of
2 b# _7 a, z, n2 n& uthe motor and the personnel using the motor. / D! X( l7 Z9 N1 P& A% ~1 W9 c
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Motor Control Topics
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There are four major motor control topics or categories to consider. Each of these has several 4 E& g) A9 P0 n; I3 H. a! S5 B
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor 9 `# d& h0 Q4 s' D# L1 W4 t. M& H' A5 e
control equipment can accomplish multiple functions from each of the topics or categories. " D. f' B! b0 L
* z- r- h$ \7 e& w4 jThe four categories include: / N+ s& k9 B( Z+ l+ M
* b0 K' [' Q D) d1) Starting the Motor
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2 Q# o3 V+ j7 v4 P' A' Q' B$ aDisconnecting Means * E$ u9 o4 P# y& j) \: |2 q" i
Across the Line Starting
6 v6 w3 C+ y) lReduced Voltage Starting
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2) Motor Protection
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Overcurrent Protection
5 Z* U$ C, o) V: S# k3 f% {Overload Protection : x/ U: y5 R( R% V7 m6 F
Other Protection (voltage, phase, etc) 0 {2 [" g4 p& Z4 ]. W1 _1 X
Environment 0 s) H0 D/ \( Z8 ?
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, V& C1 g( `4 \8 v. I3) Stopping the Motor 6 {2 f2 @$ Q! [2 o( x( k/ n
/ l3 o$ J% C4 |, uCoasting 7 \" N; Q+ X* `% f0 @! w
Electrical Braking Y0 J* c# S6 r, q
Mechanical Braking * Y/ n/ M; k- q" y# V: A
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( E" R# Z. D* N" M) h4 c4) Motor Operational Control
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Speed Control
. r* @" S! O5 X) VReversing 0 U6 [$ V- p! y0 s; z5 {3 Q
Jogging ! H4 d# u+ k2 V& e& i
Sequence Control |
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