SLC-500 logical inputs, resetting timers/counters

[new2plcs]

Please help!
I have been working on this for so long that I am probably overthinking this setup and am missing something very basic.

I am trying to set up a 3-step process on a conveyor line controlled by a SLC-500. The first step stacks 6 sheets. I am using a photo sensor and a CTU for this step. After the stacking is complete (DN on the CTU is activated), the conveyor moves to the second station, which will be triggered by another photo sensor. When the second station is reached, a paint sprayer will be activated for 10s. I am using a TOF for this step. When the sprayer stops (DN for the TOF is activated), the conveyor will start up again and move the stack to a third station for manual unloading. Again, I am using a photo sensor to detect when the stack reaches the third station.

The trouble that I am having is:
a) creating the logical inputs that represent the control relays
and timers/counters while they're active
b) resetting the timers/counters when the DN is activated.

What am I doing wrong?

 

[CroCop]

Put the DN bit in front of the timer.
Use the DN bit on the counter to reset the counter.

If you post the program that you've got so far, I'd be happy to help you with it.

 

[Ken Moore]

Is this a continuous process? In other words while the sheets are at station 2 getting painted, are there sheets being stacked at station 1 and unloaded at station 3? If so, how are you handling the "all stations ready for advancement".
Does the unloader have to acknowledge that station 3 is empty?



Ken