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ELECTRIC MOTOR CONTROLS 7 _* K# r l* g
* F# @) y( V/ @, W# [8 v5 iOnce the proper motor is selected, understanding the many various control devices available and * p6 h# T, l% N' B, a
their uses and limitations becomes an important part related to reliable operation and protection of 1 l$ ]( B* A2 T# A. _( N! D
the motor and the personnel using the motor. , a9 T U4 O% f# M
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Motor Control Topics 6 d' L/ i5 X: @$ l* J: @4 a
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There are four major motor control topics or categories to consider. Each of these has several 5 P0 A9 C3 _+ X% Y9 m$ L: l
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
# c9 x: \$ M' L6 }control equipment can accomplish multiple functions from each of the topics or categories. , O" K2 t9 F% y7 }. a. z" s1 o
! F* }5 [9 O3 y5 S; FThe four categories include: ! ?0 Y, y+ x* C. }3 Z" V
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1) Starting the Motor
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Disconnecting Means
# U. V4 j9 t! [Across the Line Starting
~3 \3 g! H' M# I3 dReduced Voltage Starting / T8 @- L. Q6 B+ r' h
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2) Motor Protection
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Overcurrent Protection
& y. j2 T7 a9 D$ FOverload Protection
) t8 h% n6 j! oOther Protection (voltage, phase, etc) , m+ w: P' W( e( Y( M0 y) k
Environment
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3) Stopping the Motor - s4 L" f6 o! A; v
7 Y- M) C, _8 v! o2 T7 G' eCoasting
2 p$ G% i1 T, M$ s% |Electrical Braking & v |( h" T( u' \2 J% s5 D
Mechanical Braking * h8 i% {# h4 p5 _, Q7 p5 G
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4) Motor Operational Control
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Speed Control
6 Y8 u. ?9 O; n) xReversing
' R n8 V0 V* e4 m6 m# I; S" \Jogging
+ G# V$ [1 _9 U8 \1 eSequence Control |
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