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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
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the motor and the personnel using the motor. - o8 o. N1 C+ r8 G6 {
" L/ g" I# x* O9 pMotor Control Topics 8 [: J# M" d7 _7 I: c
- j) n7 ^* ?7 N) l) I5 SThere are four major motor control topics or categories to consider. Each of these has several
0 m8 K8 ^. v+ ?9 Csubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor + K0 g# Y2 r9 w. ?
control equipment can accomplish multiple functions from each of the topics or categories.
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The four categories include: 4 x/ z2 q: [0 Q& D4 ^8 C
3 Q" K/ N! ]5 m1 J/ m t1) Starting the Motor
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Disconnecting Means # c' B0 M2 V" T8 N5 }8 K, a
Across the Line Starting
4 X4 j0 d' M0 n7 H" FReduced Voltage Starting
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" |0 F( L# ~% c3 w6 h2) Motor Protection
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$ P1 w2 o/ [+ p& q* XOvercurrent Protection
- L" \- }0 z+ b4 m1 s1 XOverload Protection ; j- e+ V2 f) l1 O% T, G
Other Protection (voltage, phase, etc)
7 d* l* C5 c% c5 ?" M( M$ EEnvironment
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' l0 X& U2 O! i% F3) Stopping the Motor
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0 S( t" c. k) r+ g$ q7 HCoasting 8 Q# ~% k Z3 U0 c/ y
Electrical Braking / V( m0 m/ z3 W, m2 G0 e7 w' B L
Mechanical Braking
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% ]7 ~: r1 z5 l7 @/ w% |0 m" I4) Motor Operational Control
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& ]: F9 ~1 r$ J- o1 I# |, B* q HSpeed Control
/ v: L# N1 ?7 W/ \8 t+ n( l. v) k9 `Reversing
6 f# @. d& a5 W* k; `6 `' qJogging
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