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ELECTRIC MOTOR CONTROLS ( k- l \, E: ~8 E+ b
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Once the proper motor is selected, understanding the many various control devices available and
" _# M9 D, t; B" ^1 htheir uses and limitations becomes an important part related to reliable operation and protection of
- b# o1 C: M: Z# C4 s2 zthe motor and the personnel using the motor.
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Motor Control Topics
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There are four major motor control topics or categories to consider. Each of these has several
5 n; M! K: o. j/ ^ ?3 lsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
) @& q* g3 k8 |1 f$ k* m- Bcontrol equipment can accomplish multiple functions from each of the topics or categories. 5 r; l6 U* ^% {
" G' d* v) B: v( J0 q$ bThe four categories include:
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1) Starting the Motor
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- i, m$ n6 ~& S, w' I7 p) T4 ^; LDisconnecting Means
' y2 m6 k6 B$ `+ AAcross the Line Starting - u/ F& ^% d* u r& i: K# Z$ H! r2 c
Reduced Voltage Starting
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8 g% m2 F- x* u" |9 |$ \1 P m. V% q! R2) Motor Protection 0 T) S6 @* B$ X2 Y( E
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Overcurrent Protection
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Other Protection (voltage, phase, etc) 7 q0 l! S; l: d; k& Q# `! [. j
Environment
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4 O( S& T# _3 y' a1 m3) Stopping the Motor
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Coasting " t8 v% R; c/ r/ u* ~
Electrical Braking & Y$ ]. k) o% ?6 W
Mechanical Braking
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" R! O+ t* D! Q% B# s4) Motor Operational Control
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Speed Control 2 m( R- w8 ^/ d& K% N
Reversing
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( @- r/ F- O6 g# V; W! O' HSequence Control |
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