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ELECTRIC MOTOR CONTROLS
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2 U4 a; I. d: n& }8 }: kOnce the proper motor is selected, understanding the many various control devices available and . K0 ]7 a9 D4 a" p# A x! a
their uses and limitations becomes an important part related to reliable operation and protection of
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' b6 [9 f$ W9 G% }8 l+ OMotor Control Topics
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! @, w6 t- s, w) E& N6 P w9 ]. oThere are four major motor control topics or categories to consider. Each of these has several ; A+ B. w8 r0 m
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
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' ]6 F1 w9 Q* f6 `9 tThe four categories include:
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; D+ Y0 \ U0 E. x2 b9 n5 k, \1) Starting the Motor E- v- Z$ q# W- ~( L/ b' L
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Disconnecting Means + p! L- L7 Q1 |+ n
Across the Line Starting
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2) Motor Protection
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Overcurrent Protection & C; r8 s" d, y u5 A& v
Overload Protection
4 c5 E& n1 b: H0 bOther Protection (voltage, phase, etc)
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3) Stopping the Motor 9 \6 @/ X! d- G0 y" V7 m3 R- c8 O
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Coasting . t8 `+ r( W0 X! c4 u6 l
Electrical Braking
# f7 z* L h0 |# [. sMechanical Braking
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4) Motor Operational Control
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Speed Control ' @2 n/ }! b( x- E; F# s$ l
Reversing 2 H! s1 Z; x J: q" m) O
Jogging
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