Irrigation rain/freeze sensor

Looking to add a rain/freeze sensor to my irrigation setup. I know that rain makes a cork or sponge element expand and that causes an open circuit in a micro switch but I am curious about the freeze function. Anyone know how a typical rain/freeze sensor works to cause the open circuit?

I use my Omni Pro II to drive my irrigation system. I do not want to use the sensor as an in-line cut off switch. I want to let my Omni Pro II monitor the sensor for a simple open/closed condition and then use that info in my OPII program. As an example, I am thinking about using 2 sensors set to different rain levels as part of my program

Does it matter how it works as long as it does the job?

I have a Hunter rain/wind/temp unit which came wired with all three switches in series. When one or more conditions were violated the circuit was opened. I rewired it so each switch went to an input on my ELK and an output on my ELK went to the irrigation control to disable/enable.

Now I get email when the irrigation system is disabled/enabled and I know why.

Good luck.

PaulD said:

Looking to add a rain/freeze sensor to my irrigation setup. I know that rain makes a cork or sponge element expand and that causes an open circuit in a micro switch but I am curious about the freeze function. ...

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Sorry I don't know a real freeze-sensor which is testing the condition of water, - altough I have a collection of a lot sensors mentioned in this blog. I also think, it is much more important preventing freezing.

My solution for the freeze problem now, during winter, is very simple. As everybody knows, there are only some fluids which are not freezing:

hot water and
running water

So I'm protecting a normaly uncovered assembly with irrigationvalves with an insulating cover outside and inside 2 x 100 Watt bulbs for heating. Controlled by a normal outside temperature sensor and an ELK-system. I programmed the temp-level to switch ON, some degrees above the freezingpoint (taking 6°C).

And for other waterlines which are running near the outer walls in my house, I have some solenoids, which are -in case of near freezing temperatures- activated every hour for some minutes.

I think, a HAI-system can basicly act the same way.

Last winter this prevention worked good for me. If anyone is interested, I'll add here some images and more details.

I know some of the freeze sensors sold for alarm systems are just thermostats. . . . used one years ago to have a life alert system into a freeze alert for our family vacation home.

If you put in an HAI outdoor temp sensor, you can set temperature presets that will make the sensor's zone go "not ready" when the preset temps are exceeded.

cornutt said:

If you put in an HAI outdoor temp sensor, you can set temperature presets that will make the sensor's zone go "not ready" when the preset temps are exceeded.

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I know. I am also installing a HAI temp/humidity sensor that I expected to use as part of my control method. However, I have access to an Orbit rain/freeze sensor and I was trying to decide the best way to fold it into my setup. Just wanted to understand how the freeze function worked to see if I might want to use it in some way. Per Orbit spect, the freeze sensor triggers on 37 deg +/- 2 degrees.

I shut down my sprinkler system in the winter. But to watch and utilized with my sprinkler system I have an HAI outdoor temp sensor and 4 other outdoor temperature sensors, weather station, rain guage and Rainbird rain switch.

petec said:

I shut down my sprinkler system in the winter. But to watch and utilized with my sprinkler system I have an HAI outdoor temp sensor and 4 other outdoor temperature sensors, weather station, rain guage and Rainbird rain switch.

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Going to hijack my own thread here. Do you have a weather station tied to your OPII? If so, what brand/model, how did you do it and how do you display the info?

The weather station is indirectly connected to my OmniProII. I use some HA variables for HAI "stuff" and some HAI variables for HA "stuff".

The sprinkler system is attached to a couple of Rain8's.

I use scripting and devices on both my OmniProII and my HA server.

I am using 4 1-wire networks for weather, temps, etc. The weather station consists of:

AAG anemometer (to be replaced) providing wind speed, direction and ambient temperature
Pagoda - with a HB combo temp/humidity/light sensor
Lighting sensor - HB
Rain Guage - (2) - AAG/Dallas instruments tipping cup and homebrew using a HB dual counter
Assorted combo 1-wire sensors - HB, Midon Design, AAG, HAI (both outside and inside the house)

I use a number of variables for my sprinkler system via an application called MCS Sprinkers. It actually uses many external variables, internal variables, calculated variables for watering your lawn. Basically I have a schedule and utilize soil moisture calculations. I also installed water flow meters and that also can be utilized. Here is a quickie snapshot of the touch screen interface (showing about 1% of what it can do).



Here is a com read from a couple of the 1-wire networks using a Temp08/Temp05.

22:52:54 | Reading Sensors...
22:52:55 | Humidity #01[DC00000014C88C26]=64%
22:52:55 | Humidity #02[9600000014CAB326]=39%
22:52:56 | Wind Dirn[6600000000FF5220]=N
22:52:57 | Wind Speed[3E00000001890D1D]=00 MPH, Gust = 03
22:52:57 | Rain #01[F900000009EA8F1D]=09.14 Inch
22:52:58 | Lightning #01[FC00000007C9371D]=03218,03211
22:53:00 | Temp #01[CE0000007518D026]=77.00F
22:53:02 | Temp #02[05000800084E9210]=25.92F
22:53:02 | Temp #03[DC00000014C88C26]=58.10F
22:53:03 | Temp #04[9600000014CAB326]=64.85F

22:49:13 | Barometer #01[BD000000AEF4A726]=29.71 inHg
22:49:16 | Temp #01[D90008001347A010]=52.46F
22:49:18 | Temp #02[7B0008001356AE10]=68.90F
22:49:20 | Temp #03[BD000000AEF4A726]=92.53F
22:49:22 | Temp #04[0D00080013544A10]=76.76F
22:49:24 | Temp #05[9300080013572410]=67.87F

Click to expand...

A read from MCSXap 1-wire application:

petec said:

The weather station is indirectly connected to my OmniProII. I use some HA variables for HAI "stuff" and some HAI variables for HA "stuff".

The sprinkler system is attached to a couple of Rain8's.

I use scripting and devices on both my OmniProII and my HA server.

I am using 4 1-wire networks for weather, temps, etc. The weather station consists of:

AAG anemometer (to be replaced) providing wind speed, direction and ambient temperature
Pagoda - with a HB combo temp/humidity/light sensor
Lighting sensor - HB
Rain Guage - (2) - AAG/Dallas instruments tipping cup and homebrew using a HB dual counter
Assorted combo 1-wire sensors - HB, Midon Design, AAG, HAI (both outside and inside the house)

I use a number of variables for my sprinkler system via an application called MCS Sprinkers.

Click to expand...

That lines up with others I have seen. I was hoping to find a weather solution that I could tightly integrate with my HA setup but I have about reached the conclusion that my most likely solution will be a loose coupling between my HA system and another TBD weather station package. I am familiar with the MCS package (did not have one) and I had Rain8's for awhile but I decided to move all control to my OPII. Other than HAI temp/humidity sensors, I have never had any true weather related package but that is what I want to fold into my HA package somehow. Was checking to see if you had implemented some solution I had not yet discovered.

The only left over from the previous Rain-Bird system that I ended up using was the Rain-Bird rain sensor. As an experiment because I hadn't tried it yet I connected it to a DS10A just to see if it would work. I only have one expansion board in my OmniProII and just recently added smokes & CO detectors to it (a chore in itself).

Wondering what variables you are using in your OmniProII sprinkler system setup? Is it a static or dynamic based on variables schedule? Where I live and I believe it slowly starting to occur in other locations with city provided water there are watering restrictions based on time and day and address. In Florida versus here in the MW they went to even restricting washing your car and creating "groups" of homes with schedules in a 50 home subdivision. In the spring I had to call one week in advance to schedule for repairs of sprinkler heads (turning on the sprinkler system water to test)

petec said:

Wondering what variables you are using in your OmniProII sprinkler system setup? Is it a static or dynamic based on variables schedule?

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My irrigation system is composed of a 24VAC power supply (aka 24VAC/4Amp/8 output camera power supply), HAI relay panel and a ZAP board. The ZAP is designed to arrest electrical surges that may be picked up in underground wires from a lightning ground strike in nearby area to prevent the surge from feeding back into my system.
Control is via 2 methods. Method 1 is a PCAccess program that automatically turns individual valves on/off via HAI relay panel. The program includes "user settings" so I can alter run time or what days the system runs as desired. Method 2 is manually triggering individual valves on/off from buttons on my 5.7e touchscreen. I don't have the pretty graphics that MCS offers but I can control everything from my 5.7e touchscreens.
Right now my 5.7e control is very basic however, I have Automation Studio and I intend to jazz it up some very soon to improve the WAF.

Thanks Paul, its nice to know the different methodologies used out there in HA land.

My wife doesn't use the touch screens. My interest in the MCS application was the "tweaking" done automatically on the scheduling based on the multiple variables which cut down our water bills. (IE two years ago one of the neighbors having recently installed a sprinkler system got hit with a $900 water bill - excessive as the average is a bit over $100).

Relating to WAF it was just a remote control to "pause" or shut off the sprinkler system in case of outdoor activities.

I "was" entertaining the installation of a fertilizer system but for now I'm OK and lawn looks great.