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ELECTRIC MOTOR CONTROLS
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, k u, _% m( Y3 VOnce the proper motor is selected, understanding the many various control devices available and
3 W7 \3 L7 o9 j, y" a4 {their uses and limitations becomes an important part related to reliable operation and protection of * M2 R1 D I2 L( D8 l6 K
the motor and the personnel using the motor. + D1 V2 U3 i& Z. Z
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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
9 _* w6 Z- R+ S4 g. fsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
: ]( B" q& |! p/ Icontrol equipment can accomplish multiple functions from each of the topics or categories.
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: {# w, V: a! QThe four categories include: ! Q4 }- `$ T# q; {* V6 B& S$ T$ F
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1) Starting the Motor
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$ J3 k* W4 N n1 ^4 q; ]/ {5 TDisconnecting Means
' @+ `" W4 `3 E3 cAcross the Line Starting . t: D. J/ v9 J# V/ @
Reduced Voltage Starting
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/ W# M1 E/ k# O2) Motor Protection
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s1 ~# `3 f8 ~Overcurrent Protection 8 F: p" h, v! ~! i0 q/ |
Overload Protection
/ F6 W- O7 U1 e9 W. H1 YOther Protection (voltage, phase, etc)
, I1 ~: s* _+ m8 P4 o' Z* WEnvironment 5 y1 S5 w( d5 d' [ k
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3) Stopping the Motor
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' z4 p2 C) W# Y! `. R* HCoasting
) h( X( D; d0 {0 A( v/ Z9 F" T: ZElectrical Braking 3 R- O5 U; [: d" f& J! B
Mechanical Braking 5 `! v) S+ H) H' s
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3 D6 W; j3 B1 Q: p4) Motor Operational Control 3 }" ^ L5 U8 L( i" d" f
* y# W6 Q2 s1 Y, b$ b9 VSpeed Control & T; F' Y; u2 Q
Reversing ; F2 p7 \! V% D& l& @
Jogging 8 a8 Z3 m" D2 C* t( ]/ j; V) f
Sequence Control |
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