Measuring Rainfall with a Hydreon Sensor

[paulbates]

The Hydreon RG-11 is a non-mechanical, optical rain sensor. Its reliable, rugged and unbreakable. Based on a post by jrainey,(See post #3) I bought and installed a Hydreon sensor to emulate Tipping Bucket and measure rainfall on my property directly. Like many, I was getting mixed results by counting on results from local net based WX. It was good, but observation said it could be a lot better. This tutorial is what's needed and how to install it. It ends with a sample program to calculate rainfall.

 

What the Hydreon does

• It closes or opens (NO/NC) contacts in response to a certain amount of rain drops falling across its optics
• Each close represents a certain amount of rain fall:  .01", .001" or .0001" (There's metric too)
• The clicks are intercepted by a contact module, IO Linc
• Those clicks can be counted up, calculated into rainfall and acted on by ISY Programs

Hydreon Requirements

• 12 Volts to 30 Volts AC or DC
• A device to receive the contact clicks
• Open space to mount it

My Parts list

• Hydreon RG-11
• Insteon IO Linc 2450
• Enercell 12vdc 300ma Adapter (Radio Shack 273-315)
  • Plugs into IO Linc open outlet
• Strong 4 conductor project wire. I prefer Thermostat wire

How to do it (See pictures and diagrams)

• Hydreon

  • Set the dip switches for sensitivity. I used the default, .01" per closure

  • Feed project wire through the nut on the bottom of the Hydreon

  • Connect wire colors for power that will help you remember positive and negative

  • The positive terminal is on the far right as you connect it

  • The Normal Open (NO) and ground are on the left. Contacts don't care which wire hooks to which the IO linc

  • Mount it, clean the hydreon, and string the wire to the IOlinc location

• IOLinc and Power

  • Connect the to contact wires to IO linc's Sense and ground (see pic)

  • Cut the Enercel cable to fit. The lead with the black stripe is negative

  • Solder/Wire nut the connections from the power supply cable to the Hydreon cable

• ISY (See pic)

  • Add the IO Linc if you haven't already and name it

  • Mine is "Garage Hydreon Sensor"

  • Click options and set up per pic

  • The contact closure (NO/NC) of the IOLinc are not used for the Hydreon, they are available

• ISY Progam

  • Here is a sample, it will let you see it in action.

  • Based on the program counting up, you can set a variable and cancel your sprinkler routine

If
        Status  'Yard / Sprinklers / Garage Hydreon Sensor' is On
 
Then
        $Rain_Count += 1
 
Else
   - No Actions - (To add one, press 'Action')
 

Results

 

I've been getting good results with mine. I've been through 2 rainstorms and it seems to be close. I know exactly how much water I've been getting. My local WX stations are all over the place. My previous WX based weather saved money, but I could observe things not working right.

 

Here are other things the Hydreon can do. It can perform a number of applications together with ISY:

• "It's Raining"-- Close a skylight at the first sign of rain, and open it when it stops raining. 
• Condensation / Frost Sensing
• Wiper control
• Irrigation Control-- Turn off water if raining
• Drop Detection

[jrainey]

Excellent write up Paul.