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ELECTRIC MOTOR CONTROLS
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% ^ T6 L" O0 S9 I# \0 D6 l) }Once the proper motor is selected, understanding the many various control devices available and " _/ D5 F7 _! o5 s6 T# N( K
their uses and limitations becomes an important part related to reliable operation and protection of & g; \$ B. b1 Z4 _2 _4 F
the motor and the personnel using the motor.
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Motor Control Topics # Z, {3 j* Z) `( l
6 U* b; e4 k" m3 e: X1 BThere are four major motor control topics or categories to consider. Each of these has several - R8 K1 {. J% u- d- v0 s
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
% u* k" t2 A6 [; X; e4 Jcontrol equipment can accomplish multiple functions from each of the topics or categories.
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The four categories include: : _$ Y, h# @ M
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1) Starting the Motor 7 k, z" C6 `" [* \' g6 E& `" u3 k
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Disconnecting Means
2 Q6 v; \9 s3 m" D* e3 n+ M, UAcross the Line Starting
' A; Z7 i3 ]7 O9 k7 c1 [2 z8 QReduced Voltage Starting
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2) Motor Protection 2 g: l" R7 @, D/ b) X( x
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Overcurrent Protection 4 e' `: n! J; |0 `( M
Overload Protection : q! |6 @+ z2 ?
Other Protection (voltage, phase, etc)
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2 v7 H- i7 [5 p0 b0 R& @3) Stopping the Motor ; j: a. H b/ t5 E5 j& O, g
3 _) q& |: G: I9 \; dCoasting $ s' e* H3 C+ U3 j( k7 G
Electrical Braking * n1 _6 }% }' s) U5 s2 B6 m& M0 z
Mechanical Braking Q. n, S/ o o" P( K9 c U' f
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4) Motor Operational Control 9 }. ?7 z! a3 k2 @
2 n5 w( X- c, k- USpeed Control
: F$ ?1 e1 D6 I" mReversing : e/ G2 l! g J: R9 W7 u
Jogging
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