 鲜花( 30)  鸡蛋( 0)
|
ELECTRIC MOTOR CONTROLS 5 V _" D- u/ p% T
# c& Q! ~0 P+ i
Once the proper motor is selected, understanding the many various control devices available and 6 L+ i x3 ]8 W# Q! y/ \& t
their uses and limitations becomes an important part related to reliable operation and protection of
4 J. I- N* M* B. Z3 D3 ?/ p1 fthe motor and the personnel using the motor. # x4 g4 n% [' j) p- }% o2 _
# |7 I' F5 |9 g9 s% Q8 ?8 a
Motor Control Topics
6 s: `2 {8 n! ?* S+ o7 j/ F2 c9 @! ]5 [! J, G
There are four major motor control topics or categories to consider. Each of these has several , P B; W+ \- A3 u6 F
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor / ~2 p9 f: M" `( e! Z% a
control equipment can accomplish multiple functions from each of the topics or categories.
; l2 ^% J' U: I1 E" I2 T
. O& N3 [9 k. \The four categories include: 5 q2 C/ g- e% }
# A7 t" B, N' |: q' v2 e; E6 k
1) Starting the Motor
L3 w1 t$ t1 V' c5 x* O2 o6 B) t
/ f4 a1 n! m$ O/ D3 S. kDisconnecting Means
4 \" K! s7 B+ h+ B9 fAcross the Line Starting 3 |% f' [# r/ p+ [! S$ b
Reduced Voltage Starting
9 }$ K" W$ f$ e5 q6 H7 z' G
! d+ L& Y; X0 w5 N: T0 K! U( h+ \* N, p: B [
2) Motor Protection
) V; r/ |( g3 s4 o9 g- {& v3 d2 s, V2 i; _) q0 P
Overcurrent Protection
- M8 q3 w* N$ Y D2 }1 y% r0 v; fOverload Protection 5 b+ i: [$ A0 r+ T; ?
Other Protection (voltage, phase, etc)
9 R; F) `3 M( b; c* m6 L* ~3 l' X( ^Environment
$ ~1 h+ `- D) s- H- r+ O- E! D) G4 M; L9 A; k. @8 f4 h: o
8 ~. w2 C/ S0 ]/ P& j* b1 I# p0 x& M
3) Stopping the Motor X- V2 e- L0 I8 {9 l0 R
6 C7 Q( {: b. y7 y' Q
Coasting
* ^2 X" E6 p$ e, \Electrical Braking I+ p1 q# [- f- {: W
Mechanical Braking
/ A* Z( ^) g3 S- j+ b& S5 L1 Q, ^: L% {0 E5 [/ a1 g0 m- x
: {" d/ c' X5 G2 x4) Motor Operational Control ! O9 O" ~$ Q2 p" K4 |' `5 f8 b+ y0 D6 Z- X
' N% k8 ~' ?! \, {# x2 l8 l5 lSpeed Control
% v8 L* J! b: vReversing
" l/ w( k4 ]& F& i4 t( E! pJogging * L, P S- f9 q8 }
Sequence Control |
|