Delta Electronics DVP15MC11T, Operation Manual

Page: 120 / 601

Chapter 8 Logic Instructions
8_

Programming Example

The variable table and program
Variable name Data type Initial value
CTD1 CTD
CTD1_EN BOOL FALSE
CTD1_CD BOOL FALSE
CTD1_Load BOOL FALSE
CTD1_PV UDINT 4
CTD1_Q BOOL
CTD1_CV UDINT

Timing Chart:
Case 1
：
There is no impact on the ouput by triggering CTD1_CD when the value of CTD1_CV is
0.
Case 2
：
When CTD1_Load is TRUE and CTD1_CV equals the set value of CTD1_PV, CTD1_Q
changes from TRUE to FALSE. At the moment, CTD1_CV does not count down when
CTD1_CD is triggered.
Case 3
：
If CTD counts down normally and CTD1_Load is FALSE, the value of CTD1_CV is
decreased by 1 whenever CTD1_CD is triggered once. CTD1_Q is TRUE when the
value of CTD1_CV is decreased to 0.
1
CTD
EN ENO
Q
CTD1
CD
Q
Lo ad
CV
P V
CTD1 _EN
CTD1_CD
CTD1_Lo ad
CTD1_P V
CTD1_ Q
CTD1_ CV
CTD1_CD
CTD1_Lo ad
CTD1_Q
CTD1 _CV
CTD1_ PV
Cas e 1 Ca se 2 Case 3
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