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ELECTRIC MOTOR CONTROLS 3 n/ h4 j8 M: {' @6 x
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Once the proper motor is selected, understanding the many various control devices available and
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1 _; k& j0 \+ d( Q. S8 h PMotor Control Topics ; n1 m( x+ ~/ ]# m- c; R+ z/ p
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There are four major motor control topics or categories to consider. Each of these has several 9 f# K) l2 ]7 S b8 G
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor 9 c# [" X. q3 u
control equipment can accomplish multiple functions from each of the topics or categories. g+ T$ Q* ?3 |4 f2 G
" J+ s) v; h1 N5 D6 c" IThe four categories include:
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1) Starting the Motor
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Disconnecting Means
$ `4 ?+ f; v4 uAcross the Line Starting 3 i+ n" I! j# P, x
Reduced Voltage Starting # U. J$ v W( N% m* z. z D
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2) Motor Protection
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Overcurrent Protection " V0 C7 ?% E( Z, D2 J* u
Overload Protection 9 h( w3 k2 o, V& L8 n
Other Protection (voltage, phase, etc) ; @: C/ k9 e: q
Environment
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3) Stopping the Motor , v+ ]& M! F. K/ G; ]) ?
8 Z; S6 O6 ~" N# Q% gCoasting
$ T0 ]4 |" f" _$ \; hElectrical Braking 3 M" X& r4 W* s
Mechanical Braking
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8 E+ ]4 {1 l1 h- h" h+ r4) Motor Operational Control
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" L2 ~. {3 }/ f W* J9 ZSpeed Control l. g5 I2 i# C7 f9 V
Reversing 4 o* E' _1 @4 a2 R: p% g
Jogging
3 G* a1 j+ [1 WSequence Control |
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