Newbie with WH2081. Time stamps and cal ?

[mr.sneezy]

Hi All.

Got myself the WH2081. Works great thus far.

Couple of quick questions.
How do I get the 'History' readings to sync up to the hour and half hour (or is it automatically done at midnight) ?

Is there a good thread with info about time stamping ?

Is there any backdoor calibration method for the temp sensors in these, or are they unchangeable ?

Cheers,
Martin

[steve]

I'm not sure whether you're talking about the station or Cumulus?

The entries in the logger aren't timestamped, so getting them to match the clock is difficult. Even if you reset the station exactly on the hour, it's still likely that occasionally you would get entries a minute off because of the way that timestamps have to be retrospectively calculated.

You can put a temperature calibration into Cumulus; I don't know if there are any hacks you can do to the hardware to calibrate the sensor, but there are some experts here who may be able to say more about that.

[mr.sneezy]

No, I'm talking about the weather station only here, not Cumulus.
So EasyWeather works the same way I guess if there are no timestamps in the logger data.
So how does it apply the time to it ? Using the loggers own RTC or the PC's ?

That begs another question I guess, how does the logger derive a time for each log then when you use the History button view ?

Yes about the calibration, in the logger not Cumulus. I wondered if the sensors are factory trimmed, of if the logger can offset the sensor value via a hidden menu or something. Sort of like relative pressure is already.

Thanks,
Martin

Edit: PS. I see I'm conversing with the 'Great Creator' here. I'm most humbled

Edit. PSS. I have checked out your Cumulus SW and it does work fine wit the WH2081. It's not on your list of Supported Devices yet though.

[steve]

So EasyWeather works the same way I guess if there are no timestamps in the logger data.
So how does it apply the time to it ? Using the loggers own RTC or the PC's ?

Cumulus uses the PC clock, I don't know what Easyweather does.

That begs another question I guess, how does the logger derive a time for each log then when you use the History button view ?

Presumably the same way that the software does, by taking the current time and working backwards. Or perhaps the console has a timestamp for the first entry, so it can work forwards. It would be interesting to see what happens to the console history timestamps if you change the console clock.

[steve]

It would be interesting to see what happens to the console history timestamps if you change the console clock.

I tried it; I put my console clock forward a couple of hours, waited a minute or two, and then browsed the history. The timestamps are now all relative to the time that I changed the clock to.

[mr.sneezy]

I take it Cumulus doesn't read the history data out of the logger then, only record samples read out in realtime ?
I guess I'll have a play with the SW when the logger has a few days of data in it.
Martin

PS. Saw the fresh post. OK so the logger is just relative to it's own current clock time. Simple, but not fool proof.
It must also track how long ago it last sampled, and deduct that too I guess.

[steve]

I take it Cumulus doesn't read the history data out of the logger then, only record samples read out in realtime ?

It reads the history data from the logger when it starts up, to fill in the gap from when it was last closed down.