Rockwell Automation AutoMax Enhanced Ladder Language Reference Manual - Manual (Page 20)

1Ć4
1.3 Positive Transition Contact (PTI)
Use this input instruction to examine a Boolean variable for a rising edge. When the
variable changes from being off to on, the PTI instruction becomes true for one scan;
otherwise, the instruction is false.
The supported variables are:
D simple Boolean
D Boolean array element
D timer/counter status bits
Do not use these variables:
D bitĆindexed integer or double integer variables
D bitĆindexed integer or double integer array elements
Example of a Positive Transition Contact (PTI)
This rung shows that when switch1 transitions
from off to on the variable valve.open is set true
for one scan.