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ELECTRIC MOTOR CONTROLS
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Once the proper motor is selected, understanding the many various control devices available and
6 R; T5 q0 ~2 V( Mtheir uses and limitations becomes an important part related to reliable operation and protection of
7 q( C) w+ ]6 c5 g% }1 g0 dthe motor and the personnel using the motor. - J: M' _1 C) a3 M% [
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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
6 g4 f9 W7 T; z8 F4 U5 b! Psubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
/ ]3 Q' c: F6 A% J$ P: Vcontrol equipment can accomplish multiple functions from each of the topics or categories.
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The four categories include: 1 d' r) y, W g3 F
k5 V; T0 u8 ~$ q# s2 [% F1) Starting the Motor
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Disconnecting Means % \) T$ w1 V3 J% l& g
Across the Line Starting
8 W- u9 b! s0 X* d7 AReduced Voltage Starting
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& k6 N. u0 \# C* f2) Motor Protection " m, o; u3 r! p
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Overcurrent Protection
( U* ^# O. Q9 D4 JOverload Protection
% g& O% e6 t, V) J( sOther Protection (voltage, phase, etc)
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7 O3 l4 u8 j& y$ B3) Stopping the Motor
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; i: h4 L/ T7 A# s" {& mCoasting
2 ^/ H7 y& j" h) i; }Electrical Braking
- s0 \1 m; Q, R) l) I9 P% F& LMechanical Braking % \# C4 `( i% X* ?/ L) c
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) Q+ y8 k$ s+ C$ }* ]8 a9 i" ?4) Motor Operational Control
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Speed Control % c7 U0 g1 z1 q3 x+ C
Reversing ; q: y8 |! L/ j- E5 O' S
Jogging - g' h$ F$ S' T$ T( n
Sequence Control |
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