 鲜花( 30)  鸡蛋( 0)
|
ELECTRIC MOTOR CONTROLS ; C% m+ R' J: n% G
# E! D9 D$ u9 g+ MOnce the proper motor is selected, understanding the many various control devices available and
6 }3 n/ w' `5 D" T1 g+ \their uses and limitations becomes an important part related to reliable operation and protection of 1 Y. W+ l7 i( [ P$ B/ E# |
the motor and the personnel using the motor.
! [8 j4 R. ?, I( N. J& _2 q1 \: U8 @) I! x
Motor Control Topics 6 S0 R, F% Y# a$ U- t: V+ V
; z4 m1 M, _. V2 qThere are four major motor control topics or categories to consider. Each of these has several 3 ^( x- V- Y( C+ |* Z; T. Z! \8 _+ z" |
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor " o$ E1 I. G" N' J
control equipment can accomplish multiple functions from each of the topics or categories. ' ~! K! P3 U0 H7 v
+ A3 ^0 q: B' L0 \) y3 O ?The four categories include:
: d' `' F( s+ [
2 W7 W( [( ^; ~5 R1) Starting the Motor
$ i, a! |+ m3 I# T8 H' p3 C7 C5 O- W5 Q0 [% C9 F
Disconnecting Means
, M/ |. u- r& ?% B' B1 g. _9 ~Across the Line Starting
9 \6 v6 J: l* o+ |5 q5 Z$ W# UReduced Voltage Starting . M6 A" W7 l) R) J$ z3 G% z5 S
# u: S; \: f, C% ^$ t9 Q7 Z
5 P" q7 c, f. k/ x2) Motor Protection , s) e+ K$ ]# ]: l
( q% E2 `: U$ E, s6 dOvercurrent Protection
) T' u- |6 Z% k+ S M5 B9 HOverload Protection . s9 K5 M& [9 R% x, N0 z) I
Other Protection (voltage, phase, etc)
- v2 k5 Q q' q! y; v/ Z% x+ C# o" wEnvironment 9 [9 {. E4 ]$ U0 c: L* K' r
0 S( ^) h2 R5 N) n" y/ F4 W
2 }# j7 Q5 @: S7 R3) Stopping the Motor " h) _, v' m+ [- ^4 j! E
/ e8 h* s6 y' W( p5 f- w- Q( U: }; _/ BCoasting
7 |+ G8 }* n _3 `2 IElectrical Braking 0 A* w5 S/ [" p& @
Mechanical Braking
# O9 Q# E; U i' {7 l) o9 q0 K% Q, A: U/ q8 @3 {! r
" Y9 j4 i! O# ~2 o, I B% R
4) Motor Operational Control
# ^! x( ]/ M Z* e7 K! K' z9 V3 P6 w' I
Speed Control
# T7 U4 b" ^6 P! A* M" @! IReversing
" b/ o0 ]+ j% MJogging 5 i9 d. k" ^, B! Y' _$ N! h
Sequence Control |
|