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ELECTRIC MOTOR CONTROLS
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, m7 @- {/ i$ ?; U" S2 NOnce the proper motor is selected, understanding the many various control devices available and
' _8 R9 e7 I4 Z, A& { ftheir uses and limitations becomes an important part related to reliable operation and protection of
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Motor Control Topics
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: m& S, h5 e3 S& ]& m \) Q# g/ eThere are four major motor control topics or categories to consider. Each of these has several w' f" N# [* R' M
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
. l+ m# o) G1 K! ~7 Q, V0 z2 \3 R Ycontrol equipment can accomplish multiple functions from each of the topics or categories.
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( m& W" S- _- y" h# ]The four categories include: + I: v# Q- D) w2 Z0 ?( |
+ B$ o! `, }7 B7 @/ ~! f1) Starting the Motor
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+ [' {: j7 k+ G9 T: M2 G7 D4 ]Disconnecting Means
% {3 H o. {9 M' eAcross the Line Starting - V' I8 S7 A1 P7 V$ ?3 n& i8 H
Reduced Voltage Starting % k8 F" n+ `9 s3 w
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2) Motor Protection # Z( D9 `/ y: i3 x. y" a
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Overcurrent Protection % C. t1 v# N. `) W% M( B2 A8 b* B
Overload Protection 8 j: j: X- N8 N1 |9 V
Other Protection (voltage, phase, etc)
; F4 y' a2 _6 uEnvironment
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$ K. D9 J) I9 J( q' n9 ]3) Stopping the Motor
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Coasting
9 U' t- \! W( u. i( i+ hElectrical Braking & ^0 Z8 Y8 E6 X( x( v+ A
Mechanical Braking
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4) Motor Operational Control " `7 h! X0 A- }3 `# c X
' U" P! N( B2 T' w# G2 oSpeed Control
# T7 R5 f% e6 n/ G( ?6 ~Reversing
- d+ A, n* y+ t7 G7 C& uJogging 9 ]& I+ x, C9 Z3 A* Y7 d' c4 s1 u
Sequence Control |
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