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ELECTRIC MOTOR CONTROLS / H( ^* b2 X0 j9 w# K* H
/ `( M/ F$ B! i$ c) y$ M- mOnce the proper motor is selected, understanding the many various control devices available and
@& n, c* Z* n ]: M! Q4 q2 Xtheir uses and limitations becomes an important part related to reliable operation and protection of $ B8 l2 b7 m; E" }) u( v8 ~
the motor and the personnel using the motor. ) T2 B) z% g1 h9 R
# H; j/ a$ d9 h6 J8 k l8 s" D' xMotor Control Topics
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There are four major motor control topics or categories to consider. Each of these has several 0 {* y" u3 B3 [. B- o
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor ( p8 Y& t; W3 u4 `! e& O
control equipment can accomplish multiple functions from each of the topics or categories.
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% {6 c7 @$ L% D2 } t5 ?" {The four categories include:
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8 ]3 s3 e F1 @+ R2 e+ ]; t a1) Starting the Motor 1 H% w" W! C+ G3 t8 d, R
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Disconnecting Means
8 `% c$ z. ?4 {7 M" h$ a, lAcross the Line Starting
. C) w; M {! V; ?9 p" J/ eReduced Voltage Starting . E9 \" f+ `. W3 j3 k! q4 O# b" I
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2) Motor Protection
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Overcurrent Protection
$ F3 c; e7 S2 |4 E: s) IOverload Protection
a3 X. a# _/ YOther Protection (voltage, phase, etc) . ]/ w5 u: K5 B) m+ U" ~( j
Environment
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3) Stopping the Motor
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; F: ^/ D Z' Z s0 A$ T9 dCoasting
9 s$ N4 D2 D+ @6 QElectrical Braking & o9 W+ q3 m2 _8 m( f a: k; q
Mechanical Braking ) S0 O& t# d, b S1 C8 U) ?" [
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4) Motor Operational Control - x, e" U9 o5 N$ Y# ~5 Q
* ^, F2 M8 G! x; M+ B# p+ qSpeed Control
+ u" O2 B) C- Y* t- FReversing
5 N* y9 D6 c! R" l I( YJogging 5 D: w W3 F- a' w
Sequence Control |
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