15.07.2013 Views

Automatic control function programming manual ladder language

Automatic control function programming manual ladder language

Automatic control function programming manual ladder language

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Contact type Description<br />

Detects the falling edge of the input rung (FALLING TRIG).<br />

— F_T — Used to store the state of the input rung.<br />

IF the input rung is a ZERO and is a ONE, the output<br />

rung is set to ONE.<br />

ELSE, the output rung is set to ZERO.<br />

= input rung (storage of the input rung).<br />

Used to compare two numerical expressions.<br />

—[ > ]— IF the numerical comparison is TRUE, the output rung is unchanged.<br />

ELSE, the output rung is set to ZERO.<br />

Operation of the R_T Cell (Rising trig)<br />

Input R_T Output<br />

rung—————stored—————rung<br />

If (Input == 1 and Stored value == 0) then Output = 1<br />

Else Output = 0<br />

Stored value = Input<br />

Operation of the F_T Cell (Falling trig)<br />

Input F_T Output<br />

rung—————stored—————rung<br />

If (Input == 0 and Stored value == 1) then Output = 1<br />

Else Output = 0<br />

Stored value = Input<br />

5 - 8 en-938846/3

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!