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Rainfall rate wrong after changing multiplier

Discussion specific to Oregon Scientific weather stations
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Tony_J
Posts: 36
Joined: Wed 20 Aug 2014 9:35 am
Weather Station: Davis Vantage Pro 2+
Operating System: Windows 10
Location: Isle of Mull, UK
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Rainfall rate wrong after changing multiplier

Post by Tony_J » Wed 01 Oct 2014 10:21 am

I have added a larger funnel to my WMR88 rain gauge, which increases the area by a factor of 3.84, so I have changed the multiplier for rainfall in the calibration screen to 0.260 (1/3.84). The rainfall totals seem to be working fine since this change, but the rainfall rate calculated by Cumulus is now too large by a factor of ~4 (working from a manual integration of the trend graph). Anyone else suffer from this problem? Is it Cumulus that needs fixing or is there some other config parameter that I need to set?

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steve
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Re: Rainfall rate wrong after changing multiplier

Post by steve » Thu 02 Oct 2014 9:30 am

Cumulus takes the rate supplied by the console and applies the configured multiplier to it. As far I can see, the code is correct.

If you wait until it is raining, then turn on the debug log, Cumulus will log the rain packets from the console to the debug.log file. After rain has been recorded, zip up the diags folder and the debug.log file and I'll take a look. Please indicate what the rain rate shown on the console was at a particular time (this will presumably be about 4 times too big?) and what Cumulus was showing at that time.
Steve

Tony_J
Posts: 36
Joined: Wed 20 Aug 2014 9:35 am
Weather Station: Davis Vantage Pro 2+
Operating System: Windows 10
Location: Isle of Mull, UK
Contact:

Re: Rainfall rate wrong after changing multiplier

Post by Tony_J » Thu 02 Oct 2014 10:12 am

Steve -

Thanks - will do. We've been fortunate in not having much rain recently, but I believe that will change fairly soon!

Regards,
Tony

Tony_J
Posts: 36
Joined: Wed 20 Aug 2014 9:35 am
Weather Station: Davis Vantage Pro 2+
Operating System: Windows 10
Location: Isle of Mull, UK
Contact:

Re: Rainfall rate wrong after changing multiplier

Post by Tony_J » Fri 03 Oct 2014 8:37 am

Steve -

We had some rain overnight - I wasn't able to set up the logging (I was asleep!) but looking at the graphs this morning, the rainfall rate graph looks much more realistic when compared to the total rainfall measurement than the one the other day. Must have been an artifact of the way the rates are calculated/updated. I will keep an eye on it and let you know if I think there is really a problem, but looking good right now.

Thanks -

Regards,
Tony

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