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ELECTRIC MOTOR CONTROLS
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+ \1 O" K- @4 EOnce the proper motor is selected, understanding the many various control devices available and % J% ?" }# g5 F( r7 O
their uses and limitations becomes an important part related to reliable operation and protection of 3 s3 `, T0 |# Q) y' _; Q
the motor and the personnel using the motor. 3 ~% k$ w* c/ v" q$ [3 x; ^$ _+ A
! k, Y2 X9 b6 c+ n0 Y* |Motor Control Topics
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1 N% U8 V$ H e7 y! R. jThere are four major motor control topics or categories to consider. Each of these has several 3 ^4 @' m- [5 L9 i9 s
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor . M0 S: G1 I% {
control equipment can accomplish multiple functions from each of the topics or categories. / j- P- [, Y9 B
& `/ [2 N5 t( u1 w9 g( LThe four categories include: $ H( ], e7 n& a+ U! s v; k0 }, r
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1) Starting the Motor
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Disconnecting Means
. ]+ D9 }) l! @& ZAcross the Line Starting
4 S5 \( w# |+ X6 f5 o# _Reduced Voltage Starting
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2) Motor Protection
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! E7 f' k. X0 cOvercurrent Protection ) B' ]5 x+ E/ q( u' N. W' ]
Overload Protection
2 W7 D8 T b, a6 ^4 cOther Protection (voltage, phase, etc) # T z8 v# H) l1 T5 M% d
Environment
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3) Stopping the Motor , Y) Y: d H* |8 X. g4 q
; K% Z3 [- k7 `# S' uCoasting
) U0 e- m' B2 `( G2 A M4 H, BElectrical Braking
1 C9 |$ U; U7 h% MMechanical Braking
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4) Motor Operational Control : B: Z9 C. I3 v# Y7 M$ N& @( ]1 b
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Speed Control " n- Y* P* k2 Z
Reversing . o, w' z+ e1 i; V
Jogging
+ c6 I& m3 w2 I- eSequence Control |
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