What do the readings displayed on my SDI-12 GroPoint Display Unit represent?
If you have one of the GroPoint sensors connected to the GPDU, the following table breaks down how each measurement will be represented. All moisture measurements will have the units % volumetric moisture content and all temperature measurements will be in Celsius.
If you have a third party sensor connected to the GPDU, the command structure is as follows:
M! commands: the reading will be displayed as ‘VL.n ± d.ddd, where n is the measurement number in the sequence and d.ddd is the measurement value
Mx! commands: the reading will be displayed as Mx.n±d.ddd, where x is the SDI-12 measure command (M1! To M9!)
Not all SDI-12 sensors support all nine measurement commands. After the last supported measurement command, the Display Unit returns to the M! command. Not all sensors return all nine values for a measurement, most return fewer values. Refer to your sensor's user manual for details about how many values are returned for each measurement command and what units are assigned to each value.
What precision of measurements can be displayed
The SDI-12 Display Unit has four-digit display precision.
What is the connector pinout for the GPDU
The SDI-12 Display Unit comes equipped with a M12 5-pin code A female connector with the following pinout:
How do I know if the batteries need changed?
If the battery voltage drops too low, the message “*** Low Battery ***” will be displayed when the Display Unit is powered on.
How do I connect the SDI-12 Display Unit to a sensor?
The Display Unit comes equipped with a M12 5-pin code A female connector. To connect a sensor, you will either need the mating male connector on the sensor or the Alligator Clip to M12 Male Adapter for sensors with flying leads.
What type of sensors are compatible with the SDI-12 Display Unit?
Any sensors that follow the SDI-12 protocol and can operate from a nominal 9V battery supply are compatible with the Display Unit.
What type of battery does the Display Unit take?
The Display unit comes with a 9V alkaline battery installed. You will need to remove the contact cover before use. If you need to replace the battery, ensure you use a 9V alkaline battery.
What should I do if the Display Unit shows an error message?
If you get an error message, you should check your sensor connection and ensure the wiring is correct. If you are using a third-party sensor, check the sensors specification for if the sensor can be powered sufficiently from a nominal 9V battery supply. Lastly, check the Display Unit battery voltage is greater than 7.2V with a multimeter. If it is less then change the battery.
Lets you use your GP-DU SDI-12 Sensor Reader with non-GroPoint SDI-12 sensors.
P/N: 3080