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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 5 {+ e. N4 o) {; V
their uses and limitations becomes an important part related to reliable operation and protection of 4 B. d+ m }4 }5 f* C. J3 i- h6 ~
the motor and the personnel using the motor. + v9 k0 \ g" Q
1 b4 L$ m' P. W: |5 R/ O" bMotor Control Topics - n7 o) b% K) R4 W
/ O* R$ t- L' H0 sThere are four major motor control topics or categories to consider. Each of these has several 2 \( o+ B6 k8 q+ G8 n% @
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor
5 K5 {7 A& p" t* g; Qcontrol equipment can accomplish multiple functions from each of the topics or categories. ; m7 E' O0 Y0 E' V' T
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The four categories include: , L# W$ U2 B( |1 z0 v" M
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1) Starting the Motor 6 C; m+ P/ c5 J& ?
2 {( s/ I' N" T3 Q+ T+ ?0 s0 XDisconnecting Means
* y* G" Z+ @& S1 B3 z1 x* rAcross the Line Starting ( t- A; W7 `8 k: \
Reduced Voltage Starting , M! O! y% d& b, O& O
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2) Motor Protection
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* v& A, c" v. }( }$ JOvercurrent Protection 6 U2 k5 v2 j$ U7 s. g5 f- x+ O6 a
Overload Protection & {0 {, o# q& K# w4 }
Other Protection (voltage, phase, etc) 7 v& k+ i% f7 g" G+ G) A
Environment
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3) Stopping the Motor , K3 \4 A7 g4 p& q$ @+ C7 z; q* A6 [
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Coasting / k; e% `2 I% \: S+ W
Electrical Braking ; O$ k% U6 ^ @0 x9 l, g
Mechanical Braking
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; p! \- S! o. f% T B% {* }5 }5 k4) Motor Operational Control
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Speed Control $ G5 D: H2 b, _7 A! |$ ]; r' y
Reversing 0 q" \! f$ l; `
Jogging ( D- y1 E* p9 k) \7 i" E$ j8 ]7 S
Sequence Control |
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