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ELECTRIC MOTOR CONTROLS U5 n; V- b# a+ ?
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Once the proper motor is selected, understanding the many various control devices available and
7 g7 _4 A) l4 ^. i1 R1 ntheir uses and limitations becomes an important part related to reliable operation and protection of
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7 i5 v4 T& d( K- W- x4 G2 sMotor Control Topics ' L+ N- n5 `3 F# B8 ^9 q
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There are four major motor control topics or categories to consider. Each of these has several
0 G6 M3 A8 x3 K. Z" F4 Lsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor 0 i9 K: o# W s0 d4 Y; d
control equipment can accomplish multiple functions from each of the topics or categories.
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& t! t' t2 N& t3 I$ d6 M" `. kThe four categories include: " }, q! r; e L$ s
5 Z4 D( s2 z T1) Starting the Motor
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Y p- b8 \( e5 o9 {, l% oDisconnecting Means
! D0 f8 U, O& g2 m; ~- zAcross the Line Starting
2 f0 a( Z, U$ q4 C- ^2 L b% eReduced Voltage Starting
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2) Motor Protection : o' ?- H5 r3 j9 q5 c4 k
( q, J: ~! D& g4 I" ?" }! ?. xOvercurrent Protection
! w1 q+ i) d; L; Y/ ]Overload Protection 5 S: z; k- \: u3 q
Other Protection (voltage, phase, etc) 6 ]0 k/ c9 l4 |
Environment + Q& x; U: w1 L) K; g. N
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& X* R, Y G1 ~, L- c3) Stopping the Motor
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[ m5 @( ]9 i0 cCoasting 7 c2 v0 ]. T0 g
Electrical Braking ) U8 I( f$ c2 S& q) }3 [' ]
Mechanical Braking 9 J, ^2 g( Q& Y: C n( E5 u
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4) Motor Operational Control + J& b6 z* p1 E( x
) ~; G8 A: N* _, I( ^' xSpeed Control
" m" k0 i: ~+ Z9 w! {$ _8 IReversing : }3 @; |/ v( V1 y
Jogging
' h5 j$ H/ R. f2 E+ w, [ }Sequence Control |
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