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UV spike removal

From Cumulus MX version 3 build 3044 the development baton passed to Mark Crossley. Mark has been responsible for all the Builds since, and has recently released Cumulus MX version 4. He has made the code available on GitHub. It is Mark's hope that others will join in this development, but at the very least he welcomes your ideas for future developments (see Cumulus MX Development suggestions).

Moderator: mcrossley

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Mapantz
Posts: 1992
Joined: Sat 17 Dec 2011 11:55 am
Weather Station: Davis Vantage Pro2
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Location: Dorset - UK
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UV spike removal

Post by Mapantz »

Is there one for this?

I get awful UV spikes from my Davis sensors.
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rogerthn
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Re: UV spike removal

Post by rogerthn »

Settings => Calibration Settings
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ConligWX
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Re: UV spike removal

Post by ConligWX »

I dont think there is any Spike removal for UV at present.
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rogerthn
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Re: UV spike removal

Post by rogerthn »

ConligWX wrote: Wed 26 Jun 2024 10:54 am I dont think there is any Spike removal for UV at present.
Sorry, I did not expand Settings => Calibration Settings => UV Index :bash:
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Mapantz
Posts: 1992
Joined: Sat 17 Dec 2011 11:55 am
Weather Station: Davis Vantage Pro2
Operating System: Windows 11 x64
Location: Dorset - UK
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Re: UV spike removal

Post by Mapantz »

Yeah, no spike removal. I don't need to calibrate, as it would affect normal readings. I just want to stop spikes.
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mcrossley
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Re: UV spike removal

Post by mcrossley »

MX already prevents values outside the range 0-16, what would a spike be? I can see the UV changing by a considerable value between readings as normal - passing cloud, sensor coming out of a shadow etc.
Mapantz
Posts: 1992
Joined: Sat 17 Dec 2011 11:55 am
Weather Station: Davis Vantage Pro2
Operating System: Windows 11 x64
Location: Dorset - UK
Contact:

Re: UV spike removal

Post by Mapantz »

Several days back in June gave value of just over 10, which I edited. There's also quite a few several 9+.

My UV sensor is overreading, no questions there. I checked a few stations across southern counties that have Davis stations, there's no UV recordings of that magnitude.

Davis want over £200 for a reconditioned one, excluding postage and import fees. Far too much money, as is the case with Davis products.
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mcrossley
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Re: UV spike removal

Post by mcrossley »

If it is over reading, then do you not need to apply a calibration factor rather than a spike removal? Have you tried cleaning the sensor widow with some alcohol?

I agree the Davis UV sensor is very expensive, I didn't invest in one. But they are supposed to be a proper UV sensor that undergoes a calibration against multiple wavelengths before shipping. On paper you can't compare it against some cheaper items.
Mapantz
Posts: 1992
Joined: Sat 17 Dec 2011 11:55 am
Weather Station: Davis Vantage Pro2
Operating System: Windows 11 x64
Location: Dorset - UK
Contact:

Re: UV spike removal

Post by Mapantz »

I get sensible readings on clear days, so if I add a calibration, I'll end up with low readings.

I have not seen anyone else's UV sensor produce 9's and 10's when there's passing clouds etc.

I clean both my solar sensor once a month with Isopropyl, and the same with the UV since I got it.
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