The Odyssey® Depth & Temperature logger uses a pressure sensor to measure the pressure exerted by the column of water above the logger.    

Resolution:
5m - Approx 1mm.
10m - Approx 2mm.
20m - Approx 4mm.

The temperature sensor provides temperature readings with a resolution of 0.02 degrees centigrade.
 

Memory Capacity:
8190 dual sensor readings (temperature and pressure).
Min Scan Rate: 10 seconds.  
Max Scan Rate: 12 hours. 

Calibration:
The software supplied with the recorder allows linearity correction of the sensor calibration using a polynomial calculation. This will generally give a linearity of approx +/-0.1% over the full scale range of the sensor.

Logger Dimensions:
Max Diameter: 39mm.
Length: 160mm.

Vent Tube:
To achieve maximum accuracy, all underwater pressure sensors must be vented to atmosphere to remove atmospheric pressure variations from the water height measurement. The Odyssey®  data recorder uses a very tough polyethylene (PE) tubing to vent the sensor to atmospheric pressure. The top of the tube has a suspension and vent opening unit. This unit has provision for fitting a suspension line if the vent unit is to be suspended below ground level in groundwater level measurements. Vent tube is supplied with the unit but can be ordered separately if more is required.

Batteries:
2 x 1/2 AA, 3.6V, 1.2Ah Lithium Battery for use with the battery holder (included).

Applicaions:
Groundwater bores.
Surface water measurements.