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ELECTRIC MOTOR CONTROLS
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3 A+ l- n7 d* j) Y+ J* g% }Once the proper motor is selected, understanding the many various control devices available and & _( m; E' q2 v# S( i" T. m& @" b* O
their uses and limitations becomes an important part related to reliable operation and protection of
- z7 C( e ]$ ^1 V- r4 D6 Xthe motor and the personnel using the motor.
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Motor Control Topics " C2 R; i2 |/ \) p4 W; ?
$ t2 R! e- q( \" U' u2 y {There are four major motor control topics or categories to consider. Each of these has several
9 S! T7 V/ x% o9 V2 U# I% lsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
) {) N' \" z9 [control equipment can accomplish multiple functions from each of the topics or categories. : n& m g+ s! K6 B4 V6 H# ?
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The four categories include: + @. K4 ?. Y ~3 L
+ `0 \2 x) V: T0 G% `1) Starting the Motor
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Disconnecting Means
) q- d) [" B& W8 i; R- JAcross the Line Starting
, H% q; M/ L( D. K A% x3 W% ]$ I0 sReduced Voltage Starting ( t8 l& e* O3 X( P: E( V
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4 l+ b4 r: T# i& `( Z6 Z4 T+ M2) Motor Protection
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Overcurrent Protection
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Other Protection (voltage, phase, etc) 4 }* p& u) w& Y7 i# [0 j
Environment
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3) Stopping the Motor
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+ M# L. V; s0 U0 r. o n5 G0 s2 ~Coasting
" [$ _7 y- D# h xElectrical Braking 7 d7 ?# a0 K6 _/ @- Z& @
Mechanical Braking o( W1 P1 H% e. e4 A# t5 }
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4) Motor Operational Control
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8 J$ T# y4 {0 d0 Q T/ m2 K6 lSpeed Control
" y5 W( s3 g) x! BReversing 3 v- L8 \$ k R' `9 }! m
Jogging
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