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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 6 F0 ]( F( F1 w1 f( b! j
their uses and limitations becomes an important part related to reliable operation and protection of 3 k D1 f; E& f
the motor and the personnel using the motor.
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Motor Control Topics , H- k" H9 L/ a# \7 z6 |1 S
: V! O$ q; Y- Z5 lThere are four major motor control topics or categories to consider. Each of these has several
m0 b" I2 n. L) ^% I) c' E8 Ssubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
5 i" n: D( r u" ocontrol equipment can accomplish multiple functions from each of the topics or categories. ' I! S$ m5 | W# y
: z& v5 g* g; Z9 V3 j( ~' pThe four categories include: ' b2 q( u) @* i+ O: D. P. Y% t8 I
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1) Starting the Motor
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0 W( r+ G- P c; Z) a8 ?Disconnecting Means
0 {6 q: F8 @: F( F7 ^. W6 \& pAcross the Line Starting , Q. U5 X5 w) i ?* u+ |, ~
Reduced Voltage Starting
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2) Motor Protection
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9 N4 D/ P7 t4 IOvercurrent Protection
( }( ]* t. M% k z: R0 POverload Protection / _1 {0 z6 Y- }4 m3 O+ B
Other Protection (voltage, phase, etc)
# S4 G2 X6 n9 KEnvironment
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3) Stopping the Motor
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% K" l$ }/ g" y1 M. yCoasting
$ B- k) A3 q6 s0 u! e. aElectrical Braking
9 Y) O$ K {) a# _ H7 p/ q( b" ?. P1 SMechanical Braking
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3 \) V! j+ S. E P; y) k4) Motor Operational Control 9 u9 g2 s9 o, |) ^: U6 f
2 g N+ m3 K9 T6 m2 x; G& fSpeed Control ) N7 {' Y5 z x v. `' T
Reversing . U1 z1 ]; S7 ^+ R$ ^* {7 j
Jogging ' @, }; Z+ V3 P' G. b
Sequence Control |
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