Cumulus Support

My station is showing just 2.3 hours of sunshine today and it says 3.8 yesterday.

It's a lovely day, it's been sunny and hot for hours!

when I check Cumulous, the Sun light isn't on despite the Light, Solar rad and UV being up.

Setup looks OK to me. See screenshot showing station setup over the main display.



Any ideas why this wouldn't be showing as sunny?

You're still using the default settings. You're going to have to experiment with the settings until you get some that work for your location and setup. Your Solar Radiation figure looks low for bright sunshine in the middle of the day at this time of year, so you probably also need to adjust LuxToWM2 via cumulus.ini, but note that the other settings also affect the result. Your current reading is presumably less than 80% of the current theoretical max (mouse over the figure to see the current figure) hence the 'not sunny' result.

See this thread for some suggested settings: https://cumulus.hosiene.co.uk/viewtopic.php?f=13&t=6910 - but you're still going to have to experiment to get figures that work for you.

I thought the same as Steve, your w/m2 readings are too low for a bright sunny day.

Unfortunately there’s no standard solar sensor for the 3080, they all vary. Compared to mine your lux is very low, for 12.00pm I have approx. 66,500 lux 698 w/m2 and even at 4.00pm I have 53,333 lux 560 w/m2. My readings are still low compared to my previous solar sensor, but they do for my purposes.
A possible solution; (my reading at 12.00 pm 698/m2 divided by your reading at 12.00pm (?) 412 w/m2) *0.0079 (cumulus conversion factor in cumulus.ini) is 0.0134 instead of .0079.

i.e. instead of 52193 lux *0.0079 giving 412 w/m2 it will be 52193lux *0.0134 which is 699 w/m2 (against my 698w/m2).

I would also lower sun threshold from 75 to 70% (to match the % I use for figures above) and use 33 for sun min. Then, assuming sensor can see sun all day, you should get on a day such as today sun shine recorded from approx. 6.00am to 8.00pm.

NOTE revised conversion of 0.0134 based on assumption your 412w/m2 is at 12.00 noon. Even then some experimenting with may still need doing.

Colin