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ELECTRIC MOTOR CONTROLS 1 t+ a( N t# [& Y7 U
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Once the proper motor is selected, understanding the many various control devices available and
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the motor and the personnel using the motor.
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Motor Control Topics . I$ c2 ]; x6 ]) G. a4 Y
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There are four major motor control topics or categories to consider. Each of these has several , l( b7 ^9 r# B
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
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) e" L$ w- x+ W5 CThe four categories include: & @9 s' m# F7 B
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1) Starting the Motor # [$ V1 Y1 I8 F" }
. ^& R6 u9 f8 |9 }5 lDisconnecting Means ) W1 c8 [ u5 c( E, D* w7 w
Across the Line Starting
5 D8 @5 }3 @* `* l' _Reduced Voltage Starting 5 c4 Z9 F$ R1 e4 Z$ Y* g
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2) Motor Protection
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Overcurrent Protection 0 n) X2 i7 B3 H% ^4 B$ R6 t5 [( _
Overload Protection 0 _4 t; ^+ [% a1 `5 q' E+ M# r
Other Protection (voltage, phase, etc)
/ |, }$ H5 j% I% i& b/ LEnvironment
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# e9 C9 _( I) ]* s4 B3) Stopping the Motor ' m/ X4 {. p) S& |% q* W- Z" w% z, S
- l8 \: B% W8 H$ ?* O+ B' k) uCoasting 9 N% ~1 `6 d% K& i& g% o. r
Electrical Braking # m" n( f% W" Z7 u1 b8 S3 y" q
Mechanical Braking
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* {" U/ {- `$ o% d4) Motor Operational Control * h, A! x, B9 D& z6 }
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Speed Control ) K- N( s" W1 o5 i
Reversing 6 Q7 M; |! i. Y2 G; N9 r
Jogging 6 E+ E. J- j$ ^" C1 h: u: |/ p
Sequence Control |
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