 鲜花( 30)  鸡蛋( 0)
|
ELECTRIC MOTOR CONTROLS + F) p4 i5 O, O# y% U
, c5 ^. D4 L9 r1 K
Once the proper motor is selected, understanding the many various control devices available and
% W, ?0 h, I1 Ptheir uses and limitations becomes an important part related to reliable operation and protection of " Q6 b- Z8 r" d' M" j
the motor and the personnel using the motor. * v3 ]) H1 S) L" q0 ]$ l) z b5 t
: W) w+ k; E5 T* ?9 OMotor Control Topics
: O0 r, v* H/ H$ L# ?8 a) Z
5 b" L* w/ S6 K3 v8 J) ]# pThere are four major motor control topics or categories to consider. Each of these has several 6 E* v: h9 c3 y% o
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor 3 q7 Z+ q# j5 }: o$ ^% T
control equipment can accomplish multiple functions from each of the topics or categories. ' x9 U. B9 A) l' t3 Y
1 t5 h) h$ F2 U, |4 Z: M3 C3 b/ c
The four categories include:
1 `# h9 B& n) Q, H; _8 v/ [: f- k
) N3 r3 W* U* m- P( r# K" @1) Starting the Motor - k& y/ T R- ~" q% g
' g% `1 [5 R4 X% J$ G. {
Disconnecting Means ! C4 h0 _- F- p6 W i+ J" S
Across the Line Starting 8 L2 [/ g0 L: U& |
Reduced Voltage Starting
8 Z8 b$ n: f' \$ X& N4 N$ ~% |4 l; P9 E# G$ X/ Q
9 O- y" O6 {+ Y9 Q7 K2) Motor Protection 8 k& j/ M( K8 I7 }3 z& U- i
' p! T: I+ k. h- K7 k. S* C
Overcurrent Protection
9 n8 T1 m4 R, `3 d1 Y' yOverload Protection ! g' ?/ `% m1 g. g1 @
Other Protection (voltage, phase, etc) 8 j: |! n' c% G7 z
Environment
+ O8 J7 j* |3 ~3 s0 t% \5 [5 B# [
4 f' O7 F3 j0 X9 h$ S7 D+ q# Z
3) Stopping the Motor
- m5 q4 _7 U3 ~6 s8 N. `/ h( w+ m5 N$ u: d$ n8 T O
Coasting - b: |/ @+ P6 c* x1 L& b% x
Electrical Braking " V% `+ l/ h. V
Mechanical Braking 5 F' I- d+ [0 m S7 u% \
# c) s# s* \# }, l; ]6 Y$ X4 E, {2 b {+ d
4) Motor Operational Control
3 B' \* |3 h( W, ?$ a- ^
1 |$ B- o6 `# v9 o USpeed Control 0 u X2 P/ Y1 |% z" J: b# U! j
Reversing ' M' E/ L' M# P; v
Jogging $ ~4 s" D, h8 p6 W" ]- b$ F
Sequence Control |
|