louispijpers Posted September 14, 2020 Report Share Posted September 14, 2020 Hi, I have an application where the PLC/HMI is talking to VFDs in the native UniLogic hardware configuration. I have timers in my application that work fine initally; however when I turn off the 'Enable Communication' bit in any VFD instance and then turn it on again - none of the timers work properly!! I can watch the timer current value counting down and it is nowhere near the real-time value.. Is seems very buggy to me. Has anyone experienced this? Can a Unitronics engineer have a look into this at all? Regards, Louis. Link to comment Share on other sites More sharing options...
Alon Avivi Posted September 14, 2020 Report Share Posted September 14, 2020 Hello Louis, Please send the details and application to Support@unitronics.com We will check it. Link to comment Share on other sites More sharing options...
louispijpers Posted September 14, 2020 Author Report Share Posted September 14, 2020 Hey thanks, I just tried to email the code through but it didn;t send as its 21Mb. Ill cut it down to 5Mb or so and try to send it through with an explaination. Regards, Louis. Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted September 14, 2020 MVP 2023 Report Share Posted September 14, 2020 You could post a screenshot of the ladder rung with the timer and the ladder rung that shows the coil for the contact that is activating the timer. Link to comment Share on other sites More sharing options...
louispijpers Posted September 14, 2020 Author Report Share Posted September 14, 2020 FYI - on the picture the timer 'M100A_Rev TMR.out' normally open contact is not the same timer as the one in the red rectangle. All timers in the project start misbehaving once I toggle the 'Enable Communications' bit for the VFD. Please see the attached picture - I am starting to think this is a firmware bug. Link to comment Share on other sites More sharing options...
louispijpers Posted September 14, 2020 Author Report Share Posted September 14, 2020 Here is a video of the problem happening.. I added a seperate free-running timer to show whats happening: Link to comment Share on other sites More sharing options...
MVP 2023 Ausman Posted September 15, 2020 MVP 2023 Report Share Posted September 15, 2020 Just out of interest, what happens to the scan times during these changes? cheers, Aus edit add after Flex below. The reasoning behind the question is that it is possible that although the count looks regular on the screen, it may be that in fact it is being stopped then started every scan/few scans due to some other factor that is working on/off repeatedly. Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted September 15, 2020 MVP 2023 Report Share Posted September 15, 2020 Ausman asks a great question that's easy to check. Another question I have is, are the subroutines called without condition? Link to comment Share on other sites More sharing options...
louispijpers Posted September 15, 2020 Author Report Share Posted September 15, 2020 Hi Guys, Yeah the routine containing the timer is called un-conditionally. This bug is effecting every timer in the project.. It shouldn't matter if the subroutine is called un-conditionally or not; when the timer is enabled the processor 'tics' should be being used in the 'TON' instruction to account for discrepancies in cycle time - there seems to be an issue here.. I am using 1.29.111 at the moment - their tech support guys have asked me to go to the lastest (1.30.52) which has come out in the last 2 days so I'll give that a try & let you know about cycle times. Regards, Louis. Link to comment Share on other sites More sharing options...
louispijpers Posted September 16, 2020 Author Report Share Posted September 16, 2020 Hi All, New firmware has solved this one.. Ghosts in the machine unfortunately. Looking through the release notes there isn't anything that specifically addresses the issue. Regards, Louis. 1 Link to comment Share on other sites More sharing options...
MVP 2014 Simon Posted September 16, 2020 MVP 2014 Report Share Posted September 16, 2020 Hi Louis, Glad the firmware update solved it. Simon Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted September 16, 2020 MVP 2023 Report Share Posted September 16, 2020 So what were the scan times? Link to comment Share on other sites More sharing options...
louispijpers Posted September 16, 2020 Author Report Share Posted September 16, 2020 Ladder execution was around the 3500uS consistantly. I'm not sure what the scan time is - is this in the General.structure? Link to comment Share on other sites More sharing options...
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