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Oddball UV reading

Topics about the Beta trials up to Build 3043, the last build by Cumulus's founder Steve Loft. It was by this time way out of Beta but Steve wanted to keep it that way until he made a decision on his and Cumulus's future.

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mcrossley
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Oddball UV reading

Post by mcrossley »

I just noticed that on the 30/1 I had a high UV-I reading of 7.0 @ 10:35

The correct high reading should be 1.1 @ 12:00 (from the January log file).

At 10:34:34 I stopped MX 3016

At 10:34:43 I started MX 3016, realised I had something set wrong and immediately Ctrl-C'd it at 10:34:46, the diags show it was still processing the logger data at that point.

At 10:35:12 I started MX 3016 again, no indication of any errors, the midnight roll-over shows it writing the days high UV-I of 7.0

It looks like the last run caused the problem, I've never seen a bad UV reading before (or any other on the VP2). Maybe a one off, maybe due to the previous aborted run, but logged for reference.
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Re: Oddball UV reading

Post by steve »

Yes, it got the 7.0 reading from the 10:35 logger entry, you can see it in the WU and WOW 'catchup' uploads. Perhaps I have the archive data decode wrong for UV - presumably you don't often need to use logger data?
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Re: Oddball UV reading

Post by steve »

The field I'm using is the one described in the spec as follows:

Code: Select all

Field         Offset Size Dash Value Explanation
High UV Index   32     1     0       Highest UV Index value over the archive period. Units are (Watts / m2)
The given units don't inspire confidence, but that's typical of the Davis documentation. My code looks OK, AFAICT. Perhaps you could try loading a few archive entries with data logging turned on in the latest build, so we can see if it happens again and what the raw data looks like?
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Re: Oddball UV reading

Post by mcrossley »

OK, it will have to wait until I finish some plumbing and get the water back on, and until the sun comes out. I don't know which be first :lol:
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Re: Oddball UV reading

Post by steve »

Ah, hold on, I bet I know what the problem is. What the spec should actually say is that the field is in tenths of a unit. The figure you got was actually 0.7.
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Re: Oddball UV reading

Post by mcrossley »

Yes. It would have been about 0.7 at that time.
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