OpenSprinkler › Forums › OpenSprinkler Unified Firmware › Penmen-Monteith ETo method python script for possible use as weather script › Reply To: Penmen-Monteith ETo method python script for possible use as weather script
I used a pickle jar lid and a 5 minute run time to get my measurements. After doing the calculation you’ll find you need a small adjustment one way or the other but it comes out pretty close.
A run/soak cycle is a bit more on the water conservation side of things. I don’t ever allow for more than about 1/2inch of water per cycle. For my yard much more than that I get runoff and I’m just paying to see if gutters grow when you water them. That’s where that minmax file becomes important. The max should be single cycle saturation point for your yard. The script will also lean toward watering in the morning to prevent fungus growth from grass being wet at night.
I run the script every 15 min, nothing changes aside from the current weather conditions. It could reasonably be run just prior to sunrise and just prior to sunset, with no discernible difference in daily watering. If you use your WU data for something else and make a few calls I would suggest running the script 4 times a day just to make sure you get at least 1 reliable reading per day.
I’ve made a few adjustments to the script based on your response, I’ll post it in another post after I check to make sure I haven’t created any problems.