Two Issues

[Michael McSharry]

This is only a 4 minute debug. Moisture calcuations are done hourly at 7 minutes past the hour. I will need something that includes this period of time and somewhere toward the middle of the day when the expected UV is not zero.

[regularguy]

This debug file is a little larger, hopefully it has the information that you need. Thanks again for all of your help and support

[Michael McSharry]

This one goes from midnight to 6 AM. The 6AM reading for light is 0 so ET will be close to 0. The moisture calculation shows .001 inch lost and rainfall of .03 added. With what you have provided I see nothing unexpected

ComputeMoistureLevel(0) ET=0.001088927, Rain=0.03, Delta=-0.02998548, OldMoisture=0.9992687

The debug files have a file name with the time they were created and the Other Page or Windows File System will show the time they were last written. What you are looking for is something in the middle of the day when you light source in not zero. Everything you have provided so far has your UV/light input at 0 so very low ET values are computed.

[regularguy]

Okay, I will try to get some better information and debug files, I will be traveling through North Bend Washington this week so I am not sure how much info I can gather.

[regularguy]

Okay today (Monday) the ET for the day was calculated at .11, but the weather station showed that we recieved .003 inches of rain and the soil moisture rose from 103% to 109%. I have attached the debug file

[Michael McSharry]

If you look at your Zone Setup page you will likely find the Head factor of 75 rather than the default 0.75. That means your moisture loss is 100 times less than standard. Since the loss rates are very low then any rain will continue to bump is up to around 100%.

[regularguy]

Okay, thank you very much. As you suggested the head rate was indeed 75 and not 0.75, I was able to make the changes from here but unfortunately I believe that it is raining back there now. I will have to wait for the rain to stop and then see what happens. Thanks again for all of your support.

[Alan]

If you look at your Zone Setup page you will likely find the Head factor of 75 rather than the default 0.75. That means your moisture loss is 100 times less than standard. Since the loss rates are very low then any rain will continue to bump is up to around 100%.

Michael,
I have been constantly struggling with 'slow' moisture loss. Seeing your post now makes me wonder if I have mine set wrong.

1. You say it should say ".75" not "75". My Head says "75%", which of course = 0.75. So should it be "0.75" or "75" in the entry field?

2. I have also tried decreasing to "60%" head, increasing Crop to "5" and even raising Solar Intensity to "1.6" and still the loss of moisture is slow. Is this a valid thing to try?
2a. I'm a bit confused as to why I would adjust one over the other. Would you please explain?
2b Is it possible for you to post your complete formula? - this would possibly help me understand how the moisture is adjusted.

3. I just noticed one other thing: my UV value has been the same value since last month (8.8 and rounded to 9 in the calendar view). I found in the weather setup that Weather Sensor Source for UV was set to "none". I just changed that to "EPA" to see it's effect.
Could this be another source of my issues?

4. Solar Index indicates "0" in the General section. But I thought I remember you saying it's not used in the calculation. Is that right?

Thanks,

Alan

[Michael McSharry]

The zone moisture calculation is below and is executed once per hour. The ET component comes from a variety of sources depending upon the setup. The Evap and Drain factors are the Head and Crop factors on the Zone Setup. HourlyRain is from the rain sensor setup on the Weather Page.

nDelta = ((rtnET * rtnZoneCropFactor(iZone) / rtnZoneHeadFactor(iZone)) - HourlyRain)

The crop factor is intended to reflect the degree of moisture loss due to above-ground conditions such as the type of crop. The head factor was previously a drainage factor to reflect the below-ground conditions for moisture loss. These have evolved over time since the original release of mcsSprinklers in 2004 and having two factors is only for backward compatibilty. From a numerical perspective either factor can be used to accomplish the same result. You should use whatever is intuitive to you and likely leave the other alone.

There are factors and will typically be close to 1 and default to 1.0 for crop and 0.75 for head. There are no percentage values for these of which I am aware.

Likewise over the years the method of obtaining a degree of solar radiation has changed. Originally it was based upon an algorithm that used the difference between the in-sun vs. in-shade local temperture. This is when the solar intensity had some merit. Over time the UV became generally available and an algorithm was developed based upon use of UV as a indication of solar intensity. You can still use the solar factor, but there are many users that have supported the validation of the UV algorithm with a solar factor of 1.0. When you vary from this significantly then there is no precedent for what you are doing.

The nominal settings for 0.75 for head, 1.0 for crop and 1.0 for solar are the ones you should be using and then only vary them one you get a baseline so you know what the effects of your changes are. I suspect your difficulties are with the 75 rather than 0.75 for a factor. Since you are not the first with this problem I would like to get some insight into how they become set to such large values for factors.

With V2.11 Solar Radiation was made an active device and can be used to compute ET using the most widely published PM ET algorithm. This sensor is generally not available, but there are now some WU stations that are reporting it. Generally any weather station that has a Solar Radiation sensor will also compute the ET using the PM algorrithm and then mcsSprinklers will used the ET computed rather than one it computes.

The Solar sensor, if I recall correctly, is the in-the-sun temperature measurement. If yoy do not have one then mcsSprinklers will compute it based upon the UV. If really no longer has much value, but is retained for backward compatibility.

Going forward I would set the factors to the default values. I would look at the UV and ET values on an hourly basis during any sunny day and confirm that moisture loss is consistent with the ET. A 0.25 inch/day is a good ballpark number for this time of year for moisture loss in grass.