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About jlofft

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  1. Thanks for the input everyone. Flex727. The coil in question is the last coil in the second picture "N2 Purge Ready." Essentially, is it possible the Positive Transition Coil for the HMI input to get stuck in the off setting since the button becomes invisible and thus is never checked again for the return to off state (HMI button is always true since it never "resets") Would a Positive Transition Contact resolve the issue discussed here? Seems like it would if the question above is false. Ausman. Yes, this is something I definitely try to be aware of when writing thes
  2. Hello, Thanks for the response. With regards to this "It absolutely does (if you coded the button correctly), but with a direct contact instead of a positive transition contact, it can execute many times (maybe hundreds of times) before the reset occurs because of the time it takes to remove your finger from the button." The contact is staying "true" even after the press has been released, so when the process restarts, it zips right past this section. Now there may be one aspect that is causing this: the visibility of this button is linked to the "N2 purge ready" coil on th
  3. Hi Flex727, The "positive transition contacts" suggestion in the OP actually came from a few of your older posts. First question: Why doesn't the current logic work? As in, why doesn't it reset? And with the positive transition contacts. I imagine the "Set" from the HMI is just like a latching input, so does the positive transition contact provide the "unlatch" portion as well. I see how it would work, but I like to try and understand why /how certain functions work. A better way of putting it, the positive transition stays on for one cycle when the input goes hi, wh
  4. Hi Isakovic, Thanks for the reply. I'm posted a few pictures of the actions in question. One of the buttons that does this is the "HMI_START_N2..." As you can see it's setup as a Set/Reset. The second picture shows where/how this logic executes. The issue is the reset never seems to occur. This subroutine "pre-oxidation start" is called continuously also. So it looks like unilogic just stops executing the second "reset" command. I've had other buttons do this as well with the set/reset setup and the way I've gotten around it, as stated in the original post, by using a not
  5. Hello, I'm having some issues with understanding how Unitronics integrates the HMI inputs to the PLC inputs. This is a vague start, but I have a state machine going (this project is essentially done and I've made it through it with some work-around), that requires user input to move from one state to the next. I am currently using the Set/Reset on the HMI buttons but many of the buttons seem to get stuck in the ON state (the program has moved to the next sub-state in the program), even though the logic is no longer true. Why does it do this? I see suggestions in the forums about using the po
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