How does the Chameleon sensor work?

The Chameleon is a resistance-type sensor that is calibrated to give the soil water tension or suction.  It is different from a 'Gypsum Block' sensor.  The Gypsum Block is not sensitive in the 'wetter part' of the soil moisture range (colours blue and green on the Chameleon).  The Chameleon sensor is comprised of an inner core of highly absorbent material that releases a lot of water in the 10 to 50 kPa suction range. This is coated with gypsum to provide buffering of electrical conductivity. The resistance reading is also corrected for changes in soil temperature.  

How long does the sensor last in the soil?

The expected lifespan of this sensor in the ground is 2 to 5 years, with the shorter time occurring in acidic or salty soils.  We are regularly modifying the design to increase accuracy.  We do dig up and retest sensors, but this version of the sensor is just 18 months old (and the calibrations have not shifted).      

How do I obtain a login for via.farm?

If you buy Chameleon equipment from our online shop https://viashop.csiro.au/ you will be issued account details and a farm will be created for you within a few days of completing payment.

If you are using Chameleon equipment supplied via an ACIAR funded project then you should have been issued account details.

If you have not received your account details then please contact us via the https://via.farm/contact/ page.

Please provide this following and request a login:

  • First name
  • Surname
  • Email address
  • Farm name (existing or new)
  • Your role in the project

Why are my new sensors not reading?

I have just received Chameleon sensors and a reader but the reader doesn't seem to be reading from the sensors?

The sensors when packaged for shipment are very dry. Far drier than when buried in dry soil and too dry for the reader to detect them.

When you try and read them straight out of the packet you may see the message on the reader screen "Partially plugged in". This is because the reader can only detect the temperature sensor and not the soil moisture sensors.

Before you can read the sensors you must soak them in a bucket of water for 1 hour. See the sensor installation instructions here https://via.farm/chameleon-sensor-installation-instructions/ 

What does the grey colour represent on the Visualisation?

The grey colour indicates the sensor is disconnected.

When a sensor cable is disconnected (open circuit) the reader sees it as a very high resistance. On the Visualisation anything about 4000 kOhms is assumed to be an open circuit and is colour grey to alert you to the fault. Please check your wiring, particularly at the green terminal block where it may have come loose. You will need the small flat screwdriver supplied with your reader to fix the problem.

How do I export sensor data to Excel?

You may want to export the sensor data into Excel or another program to analysis the data. You can do this following this method:

  1. Display the visualisation from the Visualise Farm, Visualise Crop, or Visualise Sensor Array pages.
  2. Click: Chameleon Data
  3. Press; Ctrl-A (to Select All)
  4. Press: Ctrl-C (to Copy)
  5. Paste into Excel
  6. Change the font colour of the heading (first row above the data) from white to black (so they can be seen).
  7. Deleted the extra rows at the top that you don't need