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ELECTRIC MOTOR CONTROLS
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1 s- |9 P8 F: Z$ e3 A' oOnce the proper motor is selected, understanding the many various control devices available and
1 s9 u$ V* J, d( ]their uses and limitations becomes an important part related to reliable operation and protection of
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# v1 K* I3 O \& ^ P+ MMotor Control Topics
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There are four major motor control topics or categories to consider. Each of these has several
* U+ s& B1 \8 n, Csubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
' ^: f' y9 i, l( |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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1) Starting the Motor
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, w: k" i+ R. i3 a3 zDisconnecting Means
2 {7 s4 g0 X' ?6 j* c q8 ]Across the Line Starting
$ c/ P q- m3 | r( tReduced Voltage Starting $ ]: I+ O5 h4 S$ W, n* l6 b% A
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2) Motor Protection ; L& G8 h0 I* h; h9 F0 a) T
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Overcurrent Protection
b* a Z' x0 J+ H/ W% w& HOverload Protection ) Y- @, S. Q: {, p& M
Other Protection (voltage, phase, etc)
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3) Stopping the Motor
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( V# x9 v5 x" a' g+ N+ P% \Coasting
+ J1 r o6 @# A2 [/ R3 D& GElectrical Braking 9 J r0 h) u! v8 y. ]& ?$ ~
Mechanical Braking
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) n( Q9 B' M) } \3 L* n7 }+ k4) Motor Operational Control 2 h+ ^- s$ j1 B, G; Y. l
+ H( b" L: h. [: mSpeed Control 8 D4 u% _) O, _% ]/ \. i( x
Reversing
+ e1 k% \3 z% m2 nJogging
) O4 x! v9 Q. Y! T1 x! Z$ ZSequence Control |
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