jmed999 Posted June 26, 2014 Posted June 26, 2014 Seems like pre 4.2.4 the irrigation requirement had a negative cap on it. So if I got 1" inch of rain it didn't go -1.0". In 4.2.4 this isn't the case. For example, a couple days ago we got about 1" of rain. My current evapo is about 0.1" per day. My current irrigation requirement is -0.7". This means in about 10 days my irrigation system will be activated through programs which require the irrigation req to be 0.3". That 1 inch of rain was great but my lawn will be very dry if I count on that 1" to keep my lawn watered for ~13 days. Am I missing something here or did the irrigation req negative cap go away in 4.2.4? Thanks!
Michel Kohanim Posted June 26, 2014 Posted June 26, 2014 Hi jmed999, It did go away due to some users having issues with mud under heavy rain. With kind regards, Michel
jmed999 Posted June 27, 2014 Author Posted June 27, 2014 SO how do we resolve the issue taking it away creates? ie. my irrigation system wont run for ~13 days...that isn't good. Is there a way to add the cap in via a program? If so what was the cap? Thanks!
swnewman Posted June 27, 2014 Posted June 27, 2014 I also noticed the large negative values. I'm not an expert on these types of watering algorithms, but it doesn't seem like the outcome of the change is ideal for keeping lawns watered on a somewhat regular basis. Could users that were having problems before use the new 24 hour rain forecast data to help with overwatering? I know I am using it to prevent irrigation if more than a quarter inch is expected in the next 24 hours.
MaddBomber83 Posted June 27, 2014 Posted June 27, 2014 You would write a program with your own negative cap and have it reset the variables. If Module 'Climate' Irrigation Requirement <= 0 inches Then Irrigation - Reset Variables Else - No Actions - (To add one, press 'Action') As a side note, Michel; negative values are not selectable from the Irrigation Requirement menu.
jmed999 Posted June 27, 2014 Author Posted June 27, 2014 What was the cap before? Simply resetting isn't the answer. If I get 1" of rain I don't want the irr req to be 0. I want it to be something like -0.25". Wouldn't that be better than resetting to 0"?
Michel Kohanim Posted June 27, 2014 Posted June 27, 2014 Hi jmed999, Are you looking to reset it to an arbitrary negative number? With kind regards, Michel
jmed999 Posted June 28, 2014 Author Posted June 28, 2014 I'm not exactly sure what it was doing before 4.2.4 but I wish there was a way to set it to do what it did before. Otherwise we will have to manually water our lawns a couple days after each rain. Thanks!
Michel Kohanim Posted June 29, 2014 Posted June 29, 2014 Hi jmed999, What Michael suggested does precisely what we did prior to 4.2.x release. With kind regards, Michel
jmed999 Posted June 29, 2014 Author Posted June 29, 2014 Hi jmed999, What Michael suggested does precisely what we did prior to 4.2.x release. With kind regards, Michel Sorry...who is Michael?
bipto Posted June 29, 2014 Posted June 29, 2014 Glad I saw this thread - this has had me scratching my head for a few days now... I've been setting up / observing my newly-purchased irrigation module, and I started on a day when we got just under an inch of rain. Now today, after 3 consecutive sunny 85+ degree days I see that the irrigation requirement is still negative. I'm not yet using these results to schedule my watering, but I'm betting that if I was the sunniest parts of my lawn would be getting pretty crispy... So forgive the noob question, but does the evapotranspiration value represent the amount of water that needs to be replaced / applied on a daily basis..? If so, I would think that value could be used in conjunction with the Total Rain Today value to come up with a suitable work-around requirement estimate in these situations, no..?
MaddBomber83 Posted June 29, 2014 Posted June 29, 2014 From the Wiki Evapotranspiration - approximation of the total amount of water leaving via a combination of soil evaporation and plant transpiration. Irrigation Requirement - amount of water to be applied based on the accumulation of previous day(s) water deficits. Yesterday's Water Deficit - total amount of water that has evapotranspired during a twenty four hour window from the day before. You could use Evapotranspiration, but maybe Yesterday's Water Deficit would be better as it would account for any rain in the last 24 hours. To limit the negative numbers I would make sure your Absorption Factor is set properly. If that 1" of rain is applied to a 50% factor then it will start watering again in 5 days. The root of the problem looks to not be a cap on the negative value but more on proper settings / trust of the calculation method. If I may offer another work around. If Irrigation Requirement is Negative Then Set State_Negative_Irrigation_Requirment = 1 Else Set State_Negative_Irrigation_Requirment = 0 If State_Negative_Irrigation_Requirment = 1 Then Wait 72 Hours Reset Irrigation Variables Using the above program would allow negative values, but if it did not water for 3 days due to negative values then it would reset it back to 0.
jmed999 Posted June 30, 2014 Author Posted June 30, 2014 Hi jmed999, What Michael suggested does precisely what we did prior to 4.2.x release. With kind regards, Michel So before 4.2.x the irrigation req never went negative?
jmed999 Posted June 30, 2014 Author Posted June 30, 2014 From the Wiki Evapotranspiration - approximation of the total amount of water leaving via a combination of soil evaporation and plant transpiration. Irrigation Requirement - amount of water to be applied based on the accumulation of previous day(s) water deficits. Yesterday's Water Deficit - total amount of water that has evapotranspired during a twenty four hour window from the day before. You could use Evapotranspiration, but maybe Yesterday's Water Deficit would be better as it would account for any rain in the last 24 hours. To limit the negative numbers I would make sure your Absorption Factor is set properly. If that 1" of rain is applied to a 50% factor then it will start watering again in 5 days. The root of the problem looks to not be a cap on the negative value but more on proper settings / trust of the calculation method. If I may offer another work around. If Irrigation Requirement is Negative Then Set State_Negative_Irrigation_Requirment = 1 Else Set State_Negative_Irrigation_Requirment = 0 If State_Negative_Irrigation_Requirment = 1 Then Wait 72 Hours Reset Irrigation Variables Using the above program would allow negative values, but if it did not water for 3 days due to negative values then it would reset it back to 0. Thanks for the info...it has been helpful! BTW, are you the Micheal that Michel was referring too?
bipto Posted July 1, 2014 Posted July 1, 2014 From the Wiki Evapotranspiration - approximation of the total amount of water leaving via a combination of soil evaporation and plant transpiration. Irrigation Requirement - amount of water to be applied based on the accumulation of previous day(s) water deficits. Yesterday's Water Deficit - total amount of water that has evapotranspired during a twenty four hour window from the day before. You could use Evapotranspiration, but maybe Yesterday's Water Deficit would be better as it would account for any rain in the last 24 hours. To limit the negative numbers I would make sure your Absorption Factor is set properly. If that 1" of rain is applied to a 50% factor then it will start watering again in 5 days. The root of the problem looks to not be a cap on the negative value but more on proper settings / trust of the calculation method. If I may offer another work around. If Irrigation Requirement is Negative Then Set State_Negative_Irrigation_Requirment = 1 Else Set State_Negative_Irrigation_Requirment = 0 If State_Negative_Irrigation_Requirment = 1 Then Wait 72 Hours Reset Irrigation Variables Using the above program would allow negative values, but if it did not water for 3 days due to negative values then it would reset it back to 0. Sure, I could see where something like this could work, thanks! And to your other point, I'm not so sure that the my issue isn't lack of faith in the algorithm either. My measuring cups got delivered today... I look forward to getting an accurate output number and then observing and experimenting from there...
jmed999 Posted July 1, 2014 Author Posted July 1, 2014 Hi jmed999, What Michael suggested does precisely what we did prior to 4.2.x release. With kind regards, Michel Sorry...who is Michael? Anyone?
jmed999 Posted July 1, 2014 Author Posted July 1, 2014 Hi jmed999, What Michael suggested does precisely what we did prior to 4.2.x release. With kind regards, Michel So before 4.2.x the irrigation req never went negative? Anyone?
MWareman Posted July 1, 2014 Posted July 1, 2014 Hi jmed999, What Michael suggested does precisely what we did prior to 4.2.x release. With kind regards, Michel Sorry...who is Michael? Anyone? Michel? or Michael? I'm (a) Michael - just an ISY owner and hobbyist. I think you may be looking for Michel from UDI though.
jmed999 Posted July 1, 2014 Author Posted July 1, 2014 Look through this thread. Michel said to do what Micheal suggested but I don't see a Micheal. Not sure what Michel meant or who he was referring to.
Michel Kohanim Posted July 1, 2014 Posted July 1, 2014 Hi jmed999, Michael, aka MWareman: If Irrigation Requirement is Negative Then Set State_Negative_Irrigation_Requirment = 1 Else Set State_Negative_Irrigation_Requirment = 0 If State_Negative_Irrigation_Requirment = 1 Then Wait 72 Hours Reset Irrigation Variables With kind regards, Michel
jmed999 Posted July 1, 2014 Author Posted July 1, 2014 Can someone please confirm the previous method (before 4.2.x) of not keeping the irrigation system from going several days after a rain. Was it, If Module 'Climate' Irrigation Requirement <= 0 inches Then Irrigation - Reset Variables Else - No Actions - (To add one, press 'Action') or If Irrigation Requirement is Negative Then Set State_Negative_Irrigation_Requirment = 1 Else Set State_Negative_Irrigation_Requirment = 0 If State_Negative_Irrigation_Requirment = 1 Then Wait 72 Hours Reset Irrigation Variables Thanks!
Michel Kohanim Posted July 1, 2014 Posted July 1, 2014 Hi jmed999, I am so very sorry the misquotation. Either one will work. One waits 72 hours to make sure the value remains negative and the other does it immediately. With kind regards, Michel
MaddBomber83 Posted July 1, 2014 Posted July 1, 2014 When you guys are using the Zone Cups could you do me a favor in the name of science? I went the el cheapo route and took some square containers and put those out in the yard to measure my output. I also did a GPH/Area conversion on the specs for my heads. Both gave me similar results. I'm wondering how much of a difference you notice using the specifically designed cups vs an off the shelf container like tupperware. Please note if you decide to do this test you should look for containers around the house that are as shallow as possible with minimal rounding on the bottom.
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