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ELECTRIC MOTOR CONTROLS , v# r: Q, M+ }7 `/ u, Y3 Y
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Once the proper motor is selected, understanding the many various control devices available and . [! D$ g) i g+ B; ?# T
their uses and limitations becomes an important part related to reliable operation and protection of ) _4 y3 M5 Q8 ^9 B. R
the motor and the personnel using the motor.
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Motor Control Topics
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9 \' I4 t5 E! @9 ?There are four major motor control topics or categories to consider. Each of these has several
. d0 }, a( J+ S3 g6 bsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
Q) k. h+ z+ L) V% `" r$ t# Acontrol equipment can accomplish multiple functions from each of the topics or categories. * [3 T- c9 ]; ~$ B0 J
7 P6 f3 D5 W7 s: T; k, B, y' }The four categories include: ; k& s* N( y q* X
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1) Starting the Motor
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Disconnecting Means
' W7 E, n& u6 n2 RAcross the Line Starting + Y+ }* Z# [8 c/ G/ E: C! S% w
Reduced Voltage Starting - b S: h' R; E0 g, P" H* x
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2) Motor Protection
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0 k8 q# j+ p5 E7 a7 G4 b, tOvercurrent Protection
* `& @2 A* [$ v; z: zOverload Protection
% {0 F K- m4 y; mOther Protection (voltage, phase, etc)
4 e' D' J1 s4 q. k/ N( SEnvironment
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3) Stopping the Motor / s1 [' F# W" G9 F/ T1 }
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Coasting ' z1 C1 N @' y \/ P$ _2 A8 `
Electrical Braking
; {5 w( o6 ], |* K" |9 QMechanical Braking
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1 q' n' O% x' ~; k, k4) Motor Operational Control 1 ~9 `8 O* O, w I' J+ B
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Speed Control ' |' @! U: Y% ?" G3 Q7 S$ D" ~
Reversing
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- I3 \+ D! V W' j9 y/ l7 vSequence Control |
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