Captured Input Digital Filter

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N e w F u n c t i o n

Ca p t u re d I n p u t

● T h e F B s s e r i e s P L C c a n s u p p o r t u p t o 3 6 p o i n ts o f c a p t u r e d i n p u t ( X 0 ~ X 3 5 )

d e p e n d i n g o n t h e m a i n u n i t . T h e i n p u t s X 0 ~ X 1 5 c a n b e c o n f i g u r e d a s t h e

h a r d w a r e i n t e r r u p t i n p u t f o r f a s t r e s p o n s e a p p l i c a t i o n , a n d t h e c a p t u r e d i n p u t s

a r e f o r l o w f r e q u e n c y b u t s h o r t d u r a t i o n ( l e s s t h a n 1 s c a n t i m e ) i n p u t s i g n a l .

● T h e p r o c e d u r e s t o c o n f i g u r e t h e c a p t u r e d i n p u t a s f o l l o wi n g s :

. E x e c u t i n g W i n P r o l a d d e r s o f t w a r e

. E n t e r ” S ys t e m C o n f i g u r e ”

à ”I/O Configure” à ”Input Setting”, then the display

w i l l b e s h o w n a s b e l o w :

● W h e n t h e i n p u t i s c o n f i g u r e d a s t h e c a p t u r e d i n p u t a n d u s e d f o r c o u n t i n g

a p p l i c a t i o n , i t i s n e c e s s a r y t h a t t h e i n p u t s i g n a l p e r i o d m u s t b e g r e a t e r t h a n 2

s c a n t i m e f o r c o r r e c t c o u n t i n g . F o r e x a m p l e t h e i n p u t f r e q u e n c y i s 5 0 H z , t h e n

t h e s c a n t i m e o f P L C m u s t b e l e s s t h a n 1 0 m S f o r c o u n t i n g w i t h o u t l o s s .

● T h e c a p t u r e d i n p u t c a n g e t t h e i n p u t s i g n a l w h i c h d u r a t i o n i s l e s s t h a n 1 s a c n

t i m e o f P L C .

Input Signal

Scan Time

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N e w F u n c t i o n

Digita l F ilte r f o r Digita l I n p u ts

● T h e F B s s e r i e s P L C m a i n u n i t s u p p o r t s t h e c a p t u r e d i n p u t f u n c t i o n a s

m e n t i o n e d a b o v e , e x c e p t t h i s , i t a l s o s u p p l i e s t h e d i g i t a l f i l t e r i n g f u n c t i o n f o r

d i g i t a l i n p u t s X 0 ~ X 3 5 . T h e r e a r e 6 g r o u p s o f d i g i t a l i n p u t s { ( X 0 ~ X 3 )、( X 4 ~ X 7 ) 、

( X 8 ~ X 11 ) 、 ( X 1 2 ~ X 1 5 ) 、 ( X 1 6 ~ X 2 3 ) 、 ( X 2 4 ~ X 3 5 ) } f o r f i l t e r i n g s e t t i n g .

● T h e r e a r e 2 m e t h o d s f o r d i g i ta l f i l t e r i n g , o n e i s t h e f r e q u e n c y d o m a i n , t h e o t h e r

i s t h e t i m e d o m a i n . T h e f i l t e r i n g s e t t i n g f o r u p p r e r f o u r g r o u p s o f d i g i t a l i n p u t s

( X 0 ~ X 1 5 ) c a n b e e i t h e r f r e q u e n c y d o m a i n o r t i m e d o m a i n ; w h i l e i n f r e q u e n c y

d o m a i n , i t s u p p o r t s t h e r a n g e o f 1 4 K H z 〜 1 . 8 M H z i n t o t a l 8 s e l e c t i o n s ; w h i l e i n

t i m e d o m a i n , i t s u p p o r t s t h e r a n g e o f 1 ~ 1 5 × 1 m S o r 1 ~ 1 5 × 0 . 1 m S s e l e c t i o n s .

T h e l a s t t w o g r o u p s o f d i g i t a l i n p u t s ( X 1 6 ~ X 3 5 ) o n l y s u p p o r t s t h e t i m e d o m a i n ,

a n d t h e s e l e c t i o n s a r e 1 ~ 1 5 × 1 m S .

B y t i m e d o m a i n , t h e d u r a t i o n o f i n p u t s i g n a l m u s t b e g r e a t e r t h a n t h e f i l t e r i n g

t i m e , t h e n t h e P L C c a n g e t t h e i n p u t s i g n a l ; b y f r e q u e n c y d o m a i n , t h e

f r e q u e n c y o f i n p u t s i g n a l m u s t b e l e s s t h a n t h e f i l t e r i n g f r e q u e n c y, t h e n t h e

P L C c a n g e t t h e i n p u t s i g n a l .

E x a m p l e 1 : W h e n t h e f i l t e r i n g t i m e i s 2 m S , i f t h e O N o r O F F d u r a t i o n i s l e s s t h a n

2 m S , i t w i l l l o s e t h e O N o r O F F s i g n a l .

Signal<2mS will be filtered

Signal>2mS can be recognized

Signal<2mS will be filtered

Signal>2mS can be recognized

Frequency>28KHz will be filtered

Frequency<28KHz can be recognized

E x a m p l e 2 : W h e n t h e f i l t e r i n g f r e q u e n c y i s 2 8 K H z , i f t h e i n p u t f r e q u e n c y i s

g r e a t e r t h a n 2 8 K H z, i t w i l l l o s e t h e i n p u t s i g n a l .

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