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ELECTRIC MOTOR CONTROLS
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Once the proper motor is selected, understanding the many various control devices available and 1 u- T$ ~7 O* i* [5 a4 J% D
their uses and limitations becomes an important part related to reliable operation and protection of 0 [1 ^* X8 g3 p+ x
the motor and the personnel using the motor. , ?) m/ S8 @/ X$ s
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Motor Control Topics
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% {% Q5 u' f PThere are four major motor control topics or categories to consider. Each of these has several : v7 z+ x& E! T
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor " N' s: f- N- }/ f
control equipment can accomplish multiple functions from each of the topics or categories. ! T# g" O: w" R3 F# P) D8 W
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The four categories include:
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, B i `3 B: v t& f9 v! i" M9 ^: e1) Starting the Motor
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! ?3 Z2 d/ C+ T; w2 hDisconnecting Means
$ E5 o& n/ V1 P( ^9 MAcross the Line Starting
; p4 O5 f0 X/ t' SReduced Voltage Starting
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* y3 \( J3 ]5 B4 _ Z& ^3 u2) Motor Protection
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" Q. |. j5 _' ^( U* u% COvercurrent Protection
. h$ `/ K' y& ROverload Protection
* U$ A& E5 m m7 SOther Protection (voltage, phase, etc)
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3) Stopping the Motor
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Coasting - T0 N& O8 v4 V6 J$ ]4 k; M( T. ^
Electrical Braking 3 x+ r1 v5 U* I% q A$ \
Mechanical Braking
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4) Motor Operational Control * H( @2 e a4 P7 @
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Speed Control
4 l: ~. ~+ I, X' Y2 M: @Reversing # q! D1 j. Q# t
Jogging " R# v w. J N$ W$ S7 e8 G
Sequence Control |
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