Cumulus Support

Hi CUMULUS Users,

I have the WMR100A which has a ~0.04" tip resolution. The values diverge (generally lower) from my manual plastic gauge.
Anyone on the BB had any luck with a device with finer resolution? I haven't found anything on the Oregon Scientific website with finer resolution.

Thanks!
Phil
http://www.climateservices.net

Hi,

The simplest solution might be to add a funnel above the rain sensor to increase the collection area by an approriate amount. Several people (including me) have done this with the Fine Offset sensor (which normally resolves to 0.3mm or 0.012 inch anyway), for example here.

I don't know what inferface the WMR100 uses, but if it's just a simple wired pulse (magnetic reed or "Hall" switch) then you might be able to buy a "spare" FO (cheap) or Davis (expensive) sensor. Or if you want real "sensitivity", the Hydreon RG11 resolves down to about 0.0001 inch or less (but not with great accuracy).

Cheers, Alan.

I don't know what your budget is, but, to answer your question, the 'RM Young tipping bucket' gets my vote every time . Accurate to 0.1mm and comes with/without heater.

Alan,

Thank you for the reply. This is an interesting gauge (specs below). 0.01" resolution, but it is a cable system. Need separate radio system. Fun stuff!

I have to punch in my manually observed B-91 data to a spreadsheet today. Will compare to the CUMULUS NOAA report. I do have some adjustments since I run CUMULUS at midnight and do manual at 7 am. "Variable end day" is on the CUMULUS enhancement list. However I think there are a lot of "gotchas" if you change the end of day hour. An interesting programming challenge.

I hope to do an in-depth analysis of the two sensor systems over the next year. My WMA100A temperature sensor seems to run "hot" when the sun is out. No surprise.

Thanks!
Phil

http://www.globalw.com/downloads/RG/RG200B.pdf

Hi,

The vast majority of rain sensors use a magnetic reed (or Hall effect) switch, so you might be able to "open up" the WMR100 and "intercept" its rain switch contacts.

The RG200 and the RM Young both appear to use simple reed switches (which can't be much simpler), so it depends to what degree you want to get involved with "homebuilt". The Hydreon is very much the exception, because although having a simple switch output, it needs a significant, continuous power supply.

Cheers, Alan.