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ELECTRIC MOTOR CONTROLS
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( Z5 `) }; p, K6 |2 I& H* _4 ^7 jOnce the proper motor is selected, understanding the many various control devices available and ( }, Z2 p6 I+ n
their uses and limitations becomes an important part related to reliable operation and protection of
4 N" x4 E5 t& M" xthe motor and the personnel using the motor.
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& r, {4 D/ B4 V$ GMotor Control Topics 4 F/ L9 T9 V4 s5 ]
7 m# E) N3 _- L+ R5 F' aThere are four major motor control topics or categories to consider. Each of these has several 3 \2 _& I! i. b- g
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor 0 U4 p$ F* N' G
control equipment can accomplish multiple functions from each of the topics or categories. : ~5 |8 x5 Y" t2 r9 d# u/ d1 P
% s: ^. Q& U/ ~The four categories include: - u" v) ?% V2 ?! V! G
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1) Starting the Motor
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) A% a# z2 g# rDisconnecting Means
6 O3 d2 ~" i, C( ]+ K q- FAcross the Line Starting
: r# g( G3 t' ~/ e2 cReduced Voltage Starting 1 n, Z) V' n E5 D& D
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2) Motor Protection
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$ E1 s6 k4 J* X$ R. k3 i) e {* eOvercurrent Protection % |: u6 l! ?7 D+ Q8 k9 H8 |
Overload Protection 2 m% ?' n4 T) C. i0 g: J# @
Other Protection (voltage, phase, etc) 4 }# C+ E$ g. x0 S! `9 n
Environment
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3) Stopping the Motor
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Coasting & f. E' a$ X6 j9 Q2 M; R" V5 u
Electrical Braking
0 W) m8 X9 j# `, D* H" M* I. O* j7 eMechanical Braking
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4) Motor Operational Control # ?& F+ D# q( p X( s" o
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Speed Control + J+ o+ P0 s$ F$ f% J
Reversing
8 B4 [2 k5 T* }! {' j2 S) FJogging 7 ^3 u$ f$ o d( F( `6 P/ w
Sequence Control |
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