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ELECTRIC MOTOR CONTROLS ! P+ b3 t' q% Q) _! R8 ]/ ]9 ]
( U# G: P6 Q" h/ Y4 ^- Z+ g5 K- nOnce the proper motor is selected, understanding the many various control devices available and
: u+ V9 U) z! `% _8 `5 k1 {9 g: M/ Etheir uses and limitations becomes an important part related to reliable operation and protection of
- M" f8 I1 T# \, d, uthe motor and the personnel using the motor.
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Motor Control Topics
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There are four major motor control topics or categories to consider. Each of these has several
# ^# C! @; O0 j1 Fsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
$ ^2 Q; {# H. C' z" scontrol equipment can accomplish multiple functions from each of the topics or categories.
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/ B5 u+ q$ t8 h- i) SThe four categories include:
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1) Starting the Motor
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Disconnecting Means
* p9 P9 n, D+ w# f @9 L. @: ?+ @Across the Line Starting
) r- U8 b: k1 y% u" _: BReduced Voltage Starting & Q" S! P- o) A0 k7 }3 e* T. D
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2) Motor Protection & m. l# I" o- u! [" l
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Overcurrent Protection w$ q& w" ]+ d- ~8 U* e
Overload Protection
! u* ]3 P0 J5 w* _' n' iOther Protection (voltage, phase, etc) 5 t2 J$ e: R9 h# J& ]
Environment
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, k: n' d! i& G( c9 c; T9 c3) Stopping the Motor
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Coasting ) h% O, i2 G& G4 k. I
Electrical Braking
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4) Motor Operational Control
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! ~% W) u! ^: ~3 aSpeed Control 2 m- `. K3 U' W8 e+ B6 H3 Q
Reversing
3 V3 k( H' `; I; ]: n+ m) E: AJogging
. i4 h! E. X: E2 |; }8 }Sequence Control |
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