I found time to get my DrDAQ wired up and logging data last night, but came across a surprise on examining the log data this morning. It appears (though this may be a coincidence) that the effectiveness of data logging decreased when the screensaver became active.
My setup, with (hopefully relevant) background information :
I'm at work, in a remote location where "mains" power is provided by one company's generators (in a ropy state - the radiator leaks several tons of difficult-to-obtain fresh water per day!) ; another company runs analytical equipment from that power supply ; I QC that second company's data ; sometimes the data goes insanely wrong, and they blame the first company's power supply dropping frequency from a nominal 50Hz to under 20Hz, but their power supply monitor is pretty ropy too (everything is ; cheapskate company).
Piggy-in-the-middle is not a comfortable place, so out of my own pocket I got a DrDAQ on my leave (I'd planned to get one one day ; this job is just my trigger), built some signal conditioning and tried to set it up last night to log the mains frequency, to resolve who is speaking "*****".
Is it working ? ... attached waveform from PicoScope : ... oh dammit, how do you attach a file in a PHPbb ... (is it a waveform or a settings file ... still new to the software. Well, the scope screenshot tells me that I've got a signal that should be usable.
I left the device running overnight, but when I got back (24x7 cover work ; sleep when you can, and be thankful for it), saw that while I'd been getting a decent-looking signal when I went off to my tent, through a lot of the night I'd not been getting good data (spreadsheet chart, attached). .
What prompted this message was my initial impression that the bad data coincides largely with the time I was off-shift, and the laptop's screensaver (plain-old screen blank with password ; no dancing penguins) had cut in. But now I'm not so sure - the spreadsheet chart suggests that the data actually improved about the time I was swearing at my alarm clock. So I may actually have a real signal, though not the one I expected.
So, two questions : does PicoLog get upset by screensavers cutting in?
Is there a (relatively) simple way to make PicoLog log times in a human-readable form, e.g. ISO 8601 YYYY-MM-DD HH:MM:SS.sss?
(I've just been told that I'm leaving the continent tomorrow, so I'm going to have to pack up now.)