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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
2 o) F: Q$ j7 g; D& p9 J! G6 }) j2 atheir uses and limitations becomes an important part related to reliable operation and protection of 8 p9 |/ k6 K0 [( Z2 w3 H
the motor and the personnel using the motor. * Q0 j F1 t/ B- B; W) q
) \0 ?( X% Z1 `. EMotor Control Topics 1 k4 k) C$ W) S; Z# w2 X9 ^* G
1 J: l* I6 E* b" r5 QThere are four major motor control topics or categories to consider. Each of these has several 9 a/ O: z O$ v% h
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
! t B1 ` s X9 u8 @control equipment can accomplish multiple functions from each of the topics or categories. ( J/ B: d* N0 R+ d( k
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The four categories include:
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8 [6 L6 ?% X) D5 ]; C1) Starting the Motor ! R* N) U5 K7 f& K. W6 x3 p
5 O2 e; U# m5 Y0 DDisconnecting Means 9 f+ Y" E9 |' T0 M- e( r
Across the Line Starting
: O7 p( w; x. J' O# d- @- XReduced Voltage Starting
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7 P) ]- z4 K4 _7 k% i- @2) Motor Protection
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- w% S' n# G# ?/ @' D0 k+ m5 pOvercurrent Protection 6 V9 a) w9 b. ]0 f' v2 ?
Overload Protection 4 {+ \- I- n# \8 E" [9 r4 W
Other Protection (voltage, phase, etc)
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" D+ m. g% ~% L+ k t3) Stopping the Motor
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Coasting 0 ^3 L0 X+ e5 v
Electrical Braking
/ [0 j3 L$ T; p# @& EMechanical Braking * J& b8 T# X0 t
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8 W( e. y% u! F0 e0 F* Y- R8 [4) Motor Operational Control
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Speed Control * r, w% @4 S. k5 J
Reversing 1 E: z' h9 m0 W0 W9 d* ]* l
Jogging , K( f! j/ n6 I) s- G' |9 u0 r
Sequence Control |
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