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ELECTRIC MOTOR CONTROLS
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+ T* _1 t j3 a# I& v# _9 gOnce the proper motor is selected, understanding the many various control devices available and
$ o( v4 ^3 ]8 _0 {their uses and limitations becomes an important part related to reliable operation and protection of / a1 m) E: f- u G7 O0 y0 @
the motor and the personnel using the motor. 1 I+ U4 }2 L0 d$ ^8 S' n4 _
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Motor Control Topics . C; D" y% p, \+ U
- f8 y, ~+ N8 j' h5 b6 K2 X$ W7 oThere are four major motor control topics or categories to consider. Each of these has several 1 E1 ^: T) h" r+ ~1 u& n: `1 C
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
2 F5 `8 e2 C! O+ A+ x% s8 Q+ ~control equipment can accomplish multiple functions from each of the topics or categories. 3 w7 f3 r4 ]1 K& L6 t
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The four categories include: ( q& }" ?$ Z! i1 l, A
* _8 ~9 N4 @( b- \* d1) Starting the Motor
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2 O9 w: S- E& R; c: |Disconnecting Means
/ ^& o; G0 |$ r: l7 OAcross the Line Starting 6 V. H3 G. `' P7 d0 G9 l" W" y
Reduced Voltage Starting
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- t; `3 v0 D3 w9 l0 D9 u% ]2) Motor Protection % }- O6 J3 S' e6 @' i
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Overcurrent Protection
! M4 o5 v9 A* u6 r6 t" u, vOverload Protection 5 h3 ?- g6 D0 L) N ~
Other Protection (voltage, phase, etc)
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3) Stopping the Motor
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. w# {& r- f3 N, RCoasting " l) x" u- X) k
Electrical Braking
; v. z5 Y7 N! z' d; y& G% hMechanical Braking
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& Q5 K7 S! _" P4) Motor Operational Control
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Speed Control * n, L; {6 s0 ~, m- o
Reversing
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Sequence Control |
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