trying to examine an input

I am trying to examine a proximity sensor during acceleration: what I am trying to accomplish is "during acceleration if there is no change in state to the poximity sensor (either stays high or low depending on last cycle) then initiate shutdown. What I am currently getting is "as soon as acceleration starts shut down". I am not sure how to examine the state of the input for

"no change" and am wondering if anyone might have some insight as to how to accomplish this? I am using an EZ420 PLC/HMI Hopefully a screenshot of my current logic (reference rungs 7-12) is attached. Thanks in advance!

Add before rung 7 if prox is made set a bit (say S250), or if not set S251

In rung 7 change the prox contact to if S250 and (not familiar with that PLC instruction set) falling edge trigger for prox, if so shutdown... and an or branch with if S251 and prox is made then shutdown

It sounds like you are looking for a 'Positive Transition' or 'Negative Transition' on that proximity sensor that will 'Set' a bit.
The 'Reset' will come after the movement.

https://www.ezautomation.net/ezplc/pdfs/instruction-set.pdf

Regards,

Thanks! I'll give it a shot and see how we go!

you need to incorporate some form of timer. either use S20 as a time test bit (check when acceleration is complete), or use a pair of timers. One timer for I16 "on" and another for I16 "off". If either timer times out, energize S210.

I ended up going the timer route and it worked to perfection, thanks to all!