[Timer On (TON) not working after re-enabling communications to VFD]

Ladder execution was around the 3500uS consistantly. I'm not sure what the scan time is - is this in the General.structure?

[Timer On (TON) not working after re-enabling communications to VFD]

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.

[Timer On (TON) not working after re-enabling communications to VFD]

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.

[Timer On (TON) not working after re-enabling communications to VFD]

Here is a video of the problem happening..

I added a seperate free-running timer to show whats happening:

 

[Timer On (TON) not working after re-enabling communications to VFD]

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. 

[Timer On (TON) not working after re-enabling communications to VFD]

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.

[Timer On (TON) not working after re-enabling communications to VFD]

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.