 鲜花( 30)  鸡蛋( 0)
|
ELECTRIC MOTOR CONTROLS 5 q" F& d M0 H/ t7 R
! z, w& R3 U( M' n9 h h
Once the proper motor is selected, understanding the many various control devices available and
% ?1 x4 i4 r/ |+ T5 `) t& Mtheir uses and limitations becomes an important part related to reliable operation and protection of 5 l( _" ^( |0 I3 W$ s2 y2 }
the motor and the personnel using the motor.
/ e" [$ U. ?* _7 n
( W/ q9 [6 U( Q' N8 W4 l! n# n0 MMotor Control Topics
9 [+ O( D1 l- d7 {- `) m0 b1 y5 z( n" D3 r# B
There are four major motor control topics or categories to consider. Each of these has several
8 Q1 @- a2 {9 [5 H n9 Rsubcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor ; C, O# t0 K/ ~4 I
control equipment can accomplish multiple functions from each of the topics or categories.
7 P* N/ N. C! a: u- t; c) n: ^' j1 q
The four categories include: 9 u j1 j5 }8 D
8 P! K) `" C. O) r- x! K
1) Starting the Motor % z5 q, r1 Z" X6 B9 `! C; \
4 [# m9 ` I# e% {- w, x! l( S/ ?Disconnecting Means
+ b- A. b9 I e \% _( W- tAcross the Line Starting
: W' E: x4 a2 B9 f& G- p. _( n4 Q" U# JReduced Voltage Starting * ? W" w, D3 } w
- @$ j) t0 k/ C+ [) w; ^0 d8 E1 G% f" p9 Z: l) Q6 d$ t
2) Motor Protection 3 G3 s Y6 z! d4 y0 Q
4 R7 }) ]; ~3 L$ D9 P7 { [
Overcurrent Protection $ n5 { J. O$ R8 R
Overload Protection
* |0 e, g, D: J$ r, OOther Protection (voltage, phase, etc)
) U9 S$ M- b% R% {! iEnvironment
2 a4 K9 Q) Q3 X: p6 A0 N X& D6 v! k* C" r
) G; m# L1 A' q, o7 h2 g
3) Stopping the Motor
5 F, q1 G% A$ s, |" ?- B( T
$ V" V. y" D$ e2 [/ C" o ECoasting
/ d6 ?# }& r7 D2 v WElectrical Braking 1 {$ W" m2 {; G& G# @* |
Mechanical Braking
# V% Y- x1 D8 q8 S
2 T7 R% |. r2 U* a& \* `- g8 m' z' ]2 {3 o
4) Motor Operational Control
: m2 y8 \: E8 u" P( I. L
5 C5 s9 s: F6 o" |Speed Control
W- I0 X: _7 b$ VReversing % f8 m% l. ~8 S1 l& Q% }* F& t7 G
Jogging
2 d& w1 m$ |! b% S" T1 y. N" CSequence Control |
|