Aric Posted November 7, 2017 Report Share Posted November 7, 2017 Noob question: How can I turn on a bit for 1 min? In all of my attempts, the timer starts counting down again when it reaches 0 and the bit stays high. Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted November 7, 2017 MVP 2023 Report Share Posted November 7, 2017 Which of the 3 types of timers are you using? Look in the Help file under Timers (T) and you'll find a very clear and detailed description of how each timer works. If you want a bit to stay on for 1 minute, one way is to use a TE timer set for 1 minute. You will need to reset it before using it again, however. Another method is to use a TD timer and Set the bit you want on for 1 min and Reset the bit when the timer expires. Link to comment Share on other sites More sharing options...
Aric Posted November 7, 2017 Author Report Share Posted November 7, 2017 I tried the TE, but it doesn't function how I think it should. Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted November 7, 2017 MVP 2023 Report Share Posted November 7, 2017 How did you think it would work? Did you read the Help file? Link to comment Share on other sites More sharing options...
Aric Posted November 7, 2017 Author Report Share Posted November 7, 2017 It turns out that a contact in my e-stop circuit was negated. Link to comment Share on other sites More sharing options...
Aric Posted November 7, 2017 Author Report Share Posted November 7, 2017 TE21 is counting down now, but the N.C. contact is open while it is counting. It is also resetting when it reaches 0. Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted November 7, 2017 MVP 2023 Report Share Posted November 7, 2017 That is an INVERTED CONTACT, not a normally closed contact. An Inverted Contact will flow power only when the bit is OFF. Link to comment Share on other sites More sharing options...
Aric Posted November 7, 2017 Author Report Share Posted November 7, 2017 how do I get the N.C. functionality from a timer? Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted November 7, 2017 MVP 2023 Report Share Posted November 7, 2017 Use a DIRECT Contact. -||- Link to comment Share on other sites More sharing options...
Aric Posted November 7, 2017 Author Report Share Posted November 7, 2017 MB216 starts TE21 and TE21 should stop MB216. Do I need to use an intermediary to get this to work? Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted November 7, 2017 MVP 2023 Report Share Posted November 7, 2017 Sorry, I'm confused about what you're trying to do. If you write your algorithm out in simple words, I can help you program it. Link to comment Share on other sites More sharing options...
Aric Posted November 7, 2017 Author Report Share Posted November 7, 2017 I need to turn on an MB216 for 1 minute and then turn off MB216. This particular project has a function that is activated when the pressure gets too high. The existing code assumes that the function will release the pressure. If it does not it runs forever and makes a mess. Also, if this happens more than three times in an hour I need to alarm. If I turn up the pressure it stays high and only counts as one event. My attempts so far, either do not turn on MB216 or it never turns off. I am sure it is easy and I am probably overlooking something. Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted November 7, 2017 MVP 2023 Report Share Posted November 7, 2017 You cannot do what you want as long as a Direct Contact for MB 1004 is in Rung 7. You either need to remove it or change it from a Direct Contact to a Positive Transition Contact. Change the MB 216 Direct Coil to a Set Coil in Rung 7, remove the contact for TE 21, and remove the contact for MB 216. Change Run 9 to: MB216 TD21 ---| |---------( )--- Add after Rung 9: TD21 MB216 ---|P|-------(R)--- Note that the above requires you to change the Timer from a TE to a TD. Link to comment Share on other sites More sharing options...
Aric Posted November 7, 2017 Author Report Share Posted November 7, 2017 like so? Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted November 7, 2017 MVP 2023 Report Share Posted November 7, 2017 No, change rung 9 & 10 to match what I posted above. Rung 7 looks right. Link to comment Share on other sites More sharing options...
Aric Posted November 7, 2017 Author Report Share Posted November 7, 2017 Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted November 7, 2017 MVP 2023 Report Share Posted November 7, 2017 Looks good. Does it work the way you expect? Link to comment Share on other sites More sharing options...
Aric Posted November 7, 2017 Author Report Share Posted November 7, 2017 No, if the pressure stays high, MB216 stays on and the timer continues to reset. Which doesn't make since because of the rising edges. Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted November 7, 2017 MVP 2023 Report Share Posted November 7, 2017 What is turning MB 216 back on? Also, what is "pressure stays high"? Which bit is that? Link to comment Share on other sites More sharing options...
Aric Posted November 7, 2017 Author Report Share Posted November 7, 2017 It turns out that the timer was use else where in the code and that was causing the reset. Thank you for all the help! Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted November 7, 2017 MVP 2023 Report Share Posted November 7, 2017 That's a common problem. Glad you got it working. Link to comment Share on other sites More sharing options...
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