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ELECTRIC MOTOR CONTROLS
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) f! x# C* g* A8 g, `/ gOnce the proper motor is selected, understanding the many various control devices available and
3 w. G/ \/ a @1 K* n1 q3 Jtheir uses and limitations becomes an important part related to reliable operation and protection of
' ?" ^, Z8 \- g5 P9 b& R( E" s3 @; @the motor and the personnel using the motor. : K& j/ z& q6 B
* G3 Q5 e5 w3 s' H0 j: uMotor Control Topics ' ? P! u! b2 {8 J8 {
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There are four major motor control topics or categories to consider. Each of these has several
- a1 Z6 d) A+ o2 y# qsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
3 w3 N. Q) L# Y7 l( x8 @2 C ocontrol equipment can accomplish multiple functions from each of the topics or categories.
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The four categories include: ) D. Z, r' S7 M( y+ e7 P( U' j- U+ t
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1) Starting the Motor
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, L' j! A) ?! ], G7 s. `Disconnecting Means # m l! |. u! g+ ~& |# m2 a; O
Across the Line Starting 8 U3 [( m' }2 C5 c, b5 r0 j9 l# h
Reduced Voltage Starting
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2) Motor Protection
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Overcurrent Protection * G" J% q/ C( `8 }) {, `
Overload Protection
% |0 M7 N$ J5 B( UOther Protection (voltage, phase, etc) / E0 n% \7 V7 y6 }7 ]
Environment : v3 X0 H* S f
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- {! I! k- c0 S$ D- i+ c" ?3) Stopping the Motor
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. Z+ s, D0 c ]! w3 `' A, n6 O: ^Coasting + R7 R \; ] u& }
Electrical Braking
; X% _4 h" b+ ]; CMechanical Braking
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1 G( q7 @- S5 e, a) W# W6 W4) Motor Operational Control
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3 R. \! J+ V2 z% W) i5 GSpeed Control
) s! f; ~- Q) V! w$ ^% GReversing ' D( H$ a6 x* h# b' [# S; q
Jogging
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