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ELECTRIC MOTOR CONTROLS
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2 t8 o3 G& h1 B% z; l4 K& cOnce the proper motor is selected, understanding the many various control devices available and . c* d7 X- y+ Z5 a- K0 K# y+ S
their uses and limitations becomes an important part related to reliable operation and protection of * s P) W+ l1 ^
the motor and the personnel using the motor.
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4 @# K# x4 G: S# |7 J! M0 JMotor Control Topics
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1 E3 _' T8 i: T6 h( ~+ K3 ZThere are four major motor control topics or categories to consider. Each of these has several % ^5 z3 h5 V7 Z. E6 N0 f
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor 7 ]5 V# v I. i% ^: ?% y! M& J8 @
control equipment can accomplish multiple functions from each of the topics or categories.
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The four categories include: ; _0 {- _" R) H* a) s' I5 v8 T
1 C! W' t5 K" y% t: I1) Starting the Motor , w% Z+ Q4 k- I$ a5 A8 G! `8 K& z$ B$ l# k
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Disconnecting Means L! O4 u8 m6 M }, E
Across the Line Starting : k- s/ L: B: T2 U# U5 ~5 O4 c
Reduced Voltage Starting
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+ s" y* r, }" B: q. F2) Motor Protection $ s3 N5 L1 [( \1 ^, N+ \
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Overcurrent Protection
9 m; r2 j3 ~; j0 i; T& H& bOverload Protection
, f0 {: z+ k- u" zOther Protection (voltage, phase, etc) . ~4 k1 A, {* |1 k# }2 o8 t
Environment & m) V- Q' H9 I+ C/ r/ r; {2 R3 W
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: m* j8 y. F& {6 y/ L+ o1 [3) Stopping the Motor
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Coasting
( q; S' ]" g7 e- eElectrical Braking 8 J5 {$ L+ U2 _3 y/ j( ?9 m5 A. R
Mechanical Braking . Y+ f: i5 l, R
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; T1 D D( w7 M4) Motor Operational Control
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9 X' ~. t, p) h SSpeed Control 9 Z7 ]8 Q e. m7 F9 [2 U
Reversing 2 ]/ K8 S0 A3 W/ ?9 V; I
Jogging
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