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ELECTRIC MOTOR CONTROLS d) I$ ^3 ]3 r( S, X8 P
7 l/ @+ i1 r- d7 N1 nOnce the proper motor is selected, understanding the many various control devices available and
5 \# t! C Q, S9 i# \( utheir uses and limitations becomes an important part related to reliable operation and protection of
/ V+ {" Z1 L, ~8 {the motor and the personnel using the motor.
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Motor Control Topics
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( n2 Q! L: z& r0 i* W0 PThere are four major motor control topics or categories to consider. Each of these has several
) i# |6 E9 \+ w; Q5 P/ o! asubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor % w- B9 R& W# y, u0 x7 X
control equipment can accomplish multiple functions from each of the topics or categories. A" ~2 l5 v! T& s W* @- S
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The four categories include: 3 N$ E# M( Z# b, e" T
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1) Starting the Motor 1 f1 U* ]8 ]7 t' b7 y1 w- z
3 n( m' G! M2 i) vDisconnecting Means + u: M; M' r% G0 f) ?$ P
Across the Line Starting
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+ {9 E$ P, J; m: Z1 }" j2) Motor Protection
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8 U; d; b) g. o' y1 f8 u( y" iOvercurrent Protection ' i0 c3 g1 g; N a& _4 }. x
Overload Protection ! J9 T3 i. q1 [9 }9 s0 [/ o
Other Protection (voltage, phase, etc)
( r- I+ x( o# }8 a0 B2 m+ y$ uEnvironment
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% \3 W: a" s& h6 ^+ v) h* n* P3) Stopping the Motor ' i5 l# O" a1 h: L
4 d% k# u% l: i K/ M% e3 mCoasting * Y$ F V" M9 N3 _
Electrical Braking ! P% N, s& v/ g0 { L. t; X$ G
Mechanical Braking ! i+ b x1 \7 f) ^( }* H2 `& N
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4) Motor Operational Control
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' q0 ]9 P7 Z, w+ n1 ^) ySpeed Control
/ |- w6 ]; H+ S+ p2 t$ bReversing 6 j: W" ^, @* @
Jogging , s8 z/ v* Z0 z7 f8 c( ^" ^' j
Sequence Control |
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