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ELECTRIC MOTOR CONTROLS + ?/ u% ^8 ]+ e: v, S U
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Once the proper motor is selected, understanding the many various control devices available and
. e" S2 F* c2 ~+ O6 ytheir uses and limitations becomes an important part related to reliable operation and protection of
. S X! p* ]' [ T1 |. Ethe motor and the personnel using the motor.
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7 E. N8 ^$ V. a R3 ~* ~Motor Control Topics
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There are four major motor control topics or categories to consider. Each of these has several
0 U% V) l/ C" F# u P0 fsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor % X8 M0 g" t7 j) A
control equipment can accomplish multiple functions from each of the topics or categories. 5 r# {' F9 s, N$ s
5 M' G# p& O: g8 y h" O9 D2 g2 pThe four categories include:
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1) Starting the Motor 9 P) s3 Y* B8 y E
& X& Y2 @1 ~# ?, f4 GDisconnecting Means 4 `1 Y' y! a6 @9 }
Across the Line Starting & U( B/ X& j# ]
Reduced Voltage Starting
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2) Motor Protection
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% Q: |# V3 u7 ?/ rOvercurrent Protection
0 q9 s- v8 ~3 U; x. u. r( bOverload Protection - K8 @6 F- V3 r: f
Other Protection (voltage, phase, etc) : m& w; o$ e2 U' P
Environment
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3) Stopping the Motor
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1 A& h/ ~) b' y( @6 W+ R M( cCoasting ( o+ l; ^0 b7 l; S8 U" k) @1 ]
Electrical Braking - X, E* O. h1 B7 v5 j9 ^
Mechanical Braking
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$ u1 S/ s; i# [% P, L: [4) Motor Operational Control
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* \' W2 W4 [2 H' e- ^* Q% O/ ?Speed Control ' }6 m3 g2 w5 @4 }" w) Z
Reversing
4 q8 ^5 O* c2 t' M6 _3 Z7 f3 O mJogging : k1 Q& I# a# g$ f
Sequence Control |
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