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ELECTRIC MOTOR CONTROLS - i. l" E( k! }& ]4 i
% ?( Y4 j( c# t t POnce the proper motor is selected, understanding the many various control devices available and
9 \# d3 n4 @& b" W/ w6 F% ]their uses and limitations becomes an important part related to reliable operation and protection of
& W4 I; L+ A# Rthe motor and the personnel using the motor. % x( T7 _8 U G/ U1 n
& _2 v, f6 D2 [2 UMotor Control Topics ) g) Y% o5 v2 |. r$ y* A; N
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There are four major motor control topics or categories to consider. Each of these has several ; z9 z2 J: k; v" h; A
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor * [5 x: C% {) S0 [" R! L
control equipment can accomplish multiple functions from each of the topics or categories.
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The four categories include: 9 p( b. f# g' ?) Q" E1 a
6 F$ W h, G! k: i* p7 B8 S5 A8 T/ d1) Starting the Motor
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! j* N+ ~+ y# r% b% T$ \: q, FDisconnecting Means ( V% n) V8 K; G! L4 d6 y5 s
Across the Line Starting
R5 m5 ]! G* A" WReduced Voltage Starting
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; o6 X: Z: ]6 P* {2) Motor Protection : P) N7 k: y4 }, @
% z( `( Z* H# R2 zOvercurrent Protection
9 s p1 a _4 f! f4 T4 iOverload Protection ; E6 B, Q, n! T8 y
Other Protection (voltage, phase, etc)
$ f2 E. E! @: ?Environment
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% Q2 R: k" U5 R3) Stopping the Motor 8 _- y; Z7 B2 g
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Coasting
* O! \3 W6 S& G( m% L" nElectrical Braking
. z8 {: A8 t7 U5 c1 o2 n. |# t6 aMechanical Braking " W+ {& z ?6 n3 R/ B+ l8 _
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" k1 d6 n8 v1 U6 ?4) Motor Operational Control 8 ^$ G. L/ Z2 m8 z6 L
2 Q' q8 W; C- E. fSpeed Control ! \) }0 S( h) l7 M# N7 [/ w
Reversing 7 }+ h( \( V5 i4 J2 j3 C; E/ h
Jogging
+ }7 d) _+ A. L% q, dSequence Control |
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