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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 . A' t* S# _4 ]" q' T; l7 [
their 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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# X" A9 ~" f0 u. gThere are four major motor control topics or categories to consider. Each of these has several
% x* G# B& I% G* T" W. \; h$ K6 Usubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
! Y8 w, O* \+ U8 d, A! ^control equipment can accomplish multiple functions from each of the topics or categories.
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The four categories include:
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3 `" G! P$ D# H/ @1 m" S: t0 U1) Starting the Motor 0 |) _/ _5 _' y& T" S
, O" J$ |; a4 W" j! Z. ]0 }7 lDisconnecting Means , g! E: P0 E) z/ l* J/ D6 }1 ^8 ~; A
Across the Line Starting
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2) Motor Protection x2 }# k: x* {8 n% \' v( I) J
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Overcurrent Protection
, z8 i5 p% u1 f- S0 d! ?9 Y$ nOverload Protection [% X+ r5 D: w) _5 q, S
Other Protection (voltage, phase, etc)
/ {9 H5 m" F4 @ V& p, a3 @Environment
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3) Stopping the Motor ; d% [' T: }* i
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Coasting
6 i8 m) t4 c# r/ IElectrical Braking
8 C% D8 w) V" x, KMechanical Braking 1 |# g8 o9 z S$ O
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4 ?: Y4 a; N- @% Q( r: Q4) Motor Operational Control
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Speed Control
a: V" U4 S( GReversing
9 y& c9 W' `4 c: uJogging
" B' A) x2 a( f1 M' c$ HSequence Control |
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发表于 2009-6-19 21:51
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