 鲜花( 30)  鸡蛋( 0)
|
ELECTRIC MOTOR CONTROLS
4 X- g& K4 b& C( s6 a6 \- K+ E$ e0 t( b& S( k/ d* x1 r. ]
Once the proper motor is selected, understanding the many various control devices available and
$ K* k4 p- l0 f) Etheir uses and limitations becomes an important part related to reliable operation and protection of
" D+ D2 ^& a D; D, h9 f5 Y z) Bthe motor and the personnel using the motor. " Q) ~. w2 p5 v" a1 [
7 B8 `$ F8 P$ \1 y+ lMotor Control Topics
: O( h) U, u9 |
- I3 Q$ l! [% D `* N' QThere are four major motor control topics or categories to consider. Each of these has several & ?4 f/ j5 B" h( @4 F% L
subcategories and sometimes the subcategories overlap to some extent. Certain pieces of motor : f5 Y, y3 R' e3 x
control equipment can accomplish multiple functions from each of the topics or categories. 0 s) C; e* U0 e
' @" v5 }8 `, Z7 U
The four categories include:
% ~& W/ b8 W9 ]6 s# }
# }. h9 {! I$ x, M0 V @8 V1) Starting the Motor 3 M) m: A1 R6 v7 H2 k. W4 S( O
0 C: E7 I6 Z5 R- m, \" H" d
Disconnecting Means
. H! X8 {6 d# G7 e+ Q4 }- Q+ W2 RAcross the Line Starting
: @ h- k7 `/ t( |0 ]6 X# f! V) aReduced Voltage Starting
1 l( g$ @ m8 q' O9 ^+ _! G
* e+ N2 g4 ?. {& R( Q9 g9 A; b" ^3 q# Q X& s$ Q
2) Motor Protection
$ S4 l2 ]- f0 T2 L/ m7 B+ q+ z9 x/ ~2 `5 L1 o$ i& R
Overcurrent Protection d7 Z1 I8 P: M( D# O C9 k
Overload Protection 6 G0 F" v% M3 }- i8 j+ Q; B
Other Protection (voltage, phase, etc) 3 I2 _" m5 T* z' ]- K2 y; ? b0 w& G! l
Environment 7 \; q% a ~ |
) G; d" i& r7 u" P0 t* ]
: I2 Q: G9 J, _& M2 `( `' Q/ v3) Stopping the Motor & t, R1 e5 B/ Q7 r- G4 C& a$ Z. t
! f* V" ^! c1 U% e2 YCoasting
/ a% Y {, b. i: z6 MElectrical Braking
$ d+ l7 p0 Q# H4 XMechanical Braking 1 p; ~( v1 U2 V
3 |, W( m ]! L: n: D$ c" a; i
0 N5 G% K8 c0 l1 E" o* I4) Motor Operational Control 0 r. n& }8 r8 s1 q) F
0 h3 M) p: T/ z# c. H. R
Speed Control J" ~% W2 |+ s; z
Reversing 1 q# A, v, K% V
Jogging ( J- F# l$ h4 L/ K* q
Sequence Control |
|
狗仔卡
发表于 2009-6-19 21:51
提升卡
置顶卡
沉默卡
喧嚣卡
变色卡
显身卡
楼主
