My solar graph plot doesn’t match the graph plot that WD shows for the expected solar
readings and this affects the number of sun hours recorded for each day. Today, for example,
was sunny all day, no clouds or haze, yet the plot looks like the first picture below. As can
be seen, the shape of the curves are not even close to being the same, so my actual solar
readings are under the expected for a large part of the day and sun hours are not recorded.
My longitude and latitude are set correctly, as is my time offset.
My set up is shown in the second picture. Does anyone have any ideas on how to correct this?
Thanks.
-Keith
In case that solar graph isn’t clear, here’s an annotated version.
Is the “Actual Solar” from an true solar sensor or calculated in WD from a UV sensor? - (As WD can calculate it from the UV rather than recorded directly from a specific solar sensor.)
TK
It’s whatever the solar/UV instrument is on the Honeywell/Irox unit. I’m not sure. However,
I would think that the shape of the curves would match, regardless of calculated vs. direct,
if the calculated curve is correct for my long/lat/TZ. But, maybe I’m wrong on that assumption.
-Keith
I believe that Honeywell/IROX station has a UV sensor and WD makes an estimate of solar radiation from the UV index. There’s another recent thread (in the home brew sensors forum IIRC) where this issue has been discussed. It is most unlikely IMHO that a UV sensor will have the correct viewing angle/spatial response to provide an accurate global solar radiation reading, so the sunshine hours estimate is unlikely to work well. Adding a 1-wire or “temp sensor in a jar” solar sensor is probably your best option.
Well, that may be the reason, Niko and, if so, there’s probably no way around it,
other than buying another station or, as you suggest, adding a different solar
sensor. Maybe I’ll just bite the bullet and get rid of this POS and get a Davis VP2
Plus… I am tired of fighting the loss of communication between the sensors and
the base, in spite of having made the base antenna mod. But, that’s a subject
for a different post.
Thanks.
-Keith
