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ELECTRIC MOTOR CONTROLS
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Once the proper motor is selected, understanding the many various control devices available and
9 u. t$ O- e8 \) i7 o+ ~7 N1 |1 Ntheir uses and limitations becomes an important part related to reliable operation and protection of
8 a$ B+ Q( ?( M5 l" }# N! ~the motor and the personnel using the motor. . \) I- f6 F6 s, g8 V2 q% @& N
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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 ; R9 K( Z& y& h/ [
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor $ N( [! f0 O& u
control equipment can accomplish multiple functions from each of the topics or categories. . S! o3 U+ }2 u$ b5 L" X
; t b/ }: C* r. _1 a) |) GThe four categories include: ! c0 r# c7 c* U: d
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1) Starting the Motor
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5 h8 @* I# N; w2 V5 C: ?Disconnecting Means
2 I& f( v" ^5 D' |1 I$ MAcross the Line Starting
2 F& R1 C3 y5 ?- nReduced Voltage Starting
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2) Motor Protection 0 e5 s5 d2 `1 T) G, A
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Overcurrent Protection + x0 T& L3 H( g4 p6 P
Overload Protection
7 i/ Y/ G* Y& w8 Z4 N2 tOther Protection (voltage, phase, etc)
/ [( Z0 u+ L, C6 mEnvironment
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9 X' Z9 Q+ y, d- O7 W4 v5 ]3) Stopping the Motor % q) `4 S t0 @1 k0 r/ d- j' L
. P7 E) i$ @# G( F1 uCoasting
$ d" v+ z5 q, |5 y7 q! [; _Electrical Braking ; X( _0 j2 Y1 m4 H
Mechanical Braking
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4) Motor Operational Control # b; M2 v( Q q% W# i+ z
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Reversing
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( d, f% _4 L/ Y7 I3 V9 P' wSequence Control |
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