The effect of this parameter seems counterintuitive. No change if I decrease it, just dots every minute. At 60 seconds, it interleaves 60-second lines with 60-second gaps. At 120 seconds it creates continuous line-segments.
If that’s not expected behaviour, please let me know if I can help isolate it further.
That makes sense. I had expected it to infer that information from the poll frequency in the Communicator settings. In my case, the input is Modbus TCP with a delay of 200 (presumably ms), so the 60s chart data period didn’t seem to be related to anything — I assumed it was a glitch in the chart plugin.
Anyhow, all better now. Thanks for your very helpful response. I’m sure this post will help the next person with this problem!