Posted 23 Oct 2023 NX1P2 unit. Conv2_timer triggers and turns on motor O_C2in_run for 4s. Looking to have the output conv1_station_Done variable become True when motor turns off, to use for triggering the next step in the sequence. On_timer_conv2 should trigger its output at the same time as Conv2_timer shuts down, which should trigger timer_conv2 and hold conv1_station_Done on for 6s. In actuality, On_timer_conv2 seems to start the countdown, but never triggers at the end of its 4 second Roll_Time. Does the TON function block not like to be held on? Is there something it doesn't like about having the two timers activate at the same time? (one off / one on) I'm sure this is a common type of action - there must be a simple solution that I'm just not seeing. Share this post Link to post Share on other sites
Posted 23 Oct 2023 Your TP timer Conv2_timer will cut off right at 4sec, turning off the control to the TON On_timer_conv2 . Not sure if the scan time will catch the input on long enough to pulse the output from the TON that sets the TP timer_conv2. Could you try something simple like this so your TP and TON are running simultaneously and the TP timer_conv2 will not set until O_C2in_run is actaully off? Share this post Link to post Share on other sites
Posted 23 Oct 2023 Actually, just breaking it up into 2 rungs solved the problem (see 1st image). However, the equivalent (unless I'm missing something) simplified version run in Simulation doesn't work (see 2nd image). TON timer T1 only outputs if I hold the input T1x on for the full 4 seconds, not if I pulse it. Share this post Link to post Share on other sites
Posted 24 Oct 2023 (edited) That is the behavior of TON function. IT only increments as long as the input is TRUE. the timer resets when the input goes FALSE. If you really want to keep the timer method you have then you could just SET the First output and use TP Conv2_timer off logic to RESET it. Edited 24 Oct 2023 by Str8jCkt Share this post Link to post Share on other sites
Posted 24 Oct 2023 If you have something that works, that's great! I would thoroughly test it. However, when I see the term 'sequence', my mind immediately goes to step programming. I'm also not a big fan of the TP instruction. I don't believe it's common across platforms. It may be simple in operation but I had to use the reference to understand it. There are many different methods of implementing sequence (or step) programming and it take a few more lines of ladder but it gives you the most flexibility and uses simple instructions. Note: you don't show the coil for Motor 2 so I made an assumption here. Share this post Link to post Share on other sites
Posted 24 Oct 2023 (edited) IO_Rack - thanks, this looks like a more robust way to do this - I'm working with a limited vocabulary of commands at this point, so it's nice to see applications for some of the other options, such as using arrays, and the Clear and Up function blocks. At this point I'm running both conveyors at the same time, so I can simplify this, but may have applications in the future where I'm sequencing them. Str8jCkt - I'll play around with these timers a bit more - between these timers and some of the ARCL function blocks, I'm having a tough time figuring out how they behave with pulse vs. continuous input. Seems like in my working program noted above, the TON timer is triggering OK from a pulse(edit - I need to verify that the input to this isn't being held by another timer). I'll play with it a bit more today, but the program that IO_Rack put out there seems to be a more robust option. Edited 24 Oct 2023 by DonNH Share this post Link to post Share on other sites