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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 ( \: T' Y3 o" Y0 _. e
their uses and limitations becomes an important part related to reliable operation and protection of ) P8 Q3 c0 \5 s9 z; T
the motor and the personnel using the motor. ?1 N" X& ?. X! |# \6 T6 K- m: N
0 u8 o+ s' I8 W7 qMotor Control Topics 3 j5 B# Q) U6 c. j$ d N0 E$ W5 C
: F3 I5 j6 t9 QThere are four major motor control topics or categories to consider. Each of these has several
9 w8 ?. a) K# bsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
& O. A* t: m6 Tcontrol equipment can accomplish multiple functions from each of the topics or categories. 4 K8 w+ G7 w0 a; _) E7 l
: B' k3 J5 _0 ~/ I+ Q$ r) wThe four categories include: 6 ~, M A9 o" o( y! N
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1) Starting the Motor
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" _) w% r! y; A* kDisconnecting Means 2 o. I# L5 S0 d$ ^/ F4 q0 j
Across the Line Starting ) C5 ?, n% u; g
Reduced Voltage Starting
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) o. |8 V O+ M5 }5 o) L% q2) Motor Protection
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Overcurrent Protection 4 Q% c: {' t8 Z3 P! d2 z
Overload Protection
0 a2 M6 |( D) k1 R( [Other Protection (voltage, phase, etc) / X$ L& q! y7 y6 j
Environment
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! D5 x4 j3 i: ^* P4 j+ U3) Stopping the Motor
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" B% j* `0 B& s4 @, iCoasting - W' n- G* p6 N, b$ r; p
Electrical Braking 4 l0 D7 w; w3 d% `2 e
Mechanical Braking
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4) Motor Operational Control
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4 V, n0 _3 U2 `4 ESpeed Control # n# U; n p \! G
Reversing
2 ~+ J- Q0 O4 @0 B1 p' A; O8 sJogging
+ s* B. P5 J7 V0 E% BSequence Control |
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