SDI-12 Digital Sensor
On-board support for statistical data processing, including filtering algorithms, averaging (take as many as 100 readings in 5 seconds), median, and B.E.S. Increase your ability to obtain the most meaningful data from any water system.
The SDI-12 digital protocol provides easy connection to any SDI-12 compatible datalogger, support for long cables, and assured data integrity. Calibration coefficients are stored on-board at the factory so sensor installation and swap-outs do not require entering calibration data into your datalogger.
The DTS-12 wiper system is the culmination of a comprehensive research and development program evaluating over 40 different cleaning technologies, lab and field tests, and years of field-based knowledge. The humble wipers combination of effectiveness, reliability, and low power requirements made it the best choice over more exotic approaches. However, traditional wipers have short life spans and can become soiled, repeatedly dragging abrasive materials and organic matter across the lens optics. The DTS-12 wiper blade parks in two grooves cut into the sensor face. These grooves extend the long term flexibility of the wiper, allow increased wiping pressure and clean the blade between wipes. Wiper changes are simple and inexpensive.
Shallow Water Capability
The DTS-12 was explicitly designed to avoid the viewing problems of other turbidity sensors. Some have large viewing volumes for a good water sampling average but are not capable of shallow-water deployment while others have shallow water capability but have a very small sampling volume. The approximately tennis ball sized view of the DTS-12 provides a good sampling volume and near-bottom deployment.
The DTS-12 features precision accuracy from 0-1600 NTU, eliminating the frustrating trade-off between low end accuracy and wide dynamic range. The sensor also offers excellent thermal and long term stability and nearly linear response over three orders of magnitude.
Laser Based Optics
The DTS-12 uses optical backscatter technology with a 780-nm laser emitter with automatic power control. It measures suspended solids with an infrared measurement system incorporating optical feedback and synchronous detection to reject ambient light. The DTS-12 features high accuracy, excellent thermal and long-term stability, and nearly linear response over three orders of magnitude.
The Angled Head
The unusual geometry of the sensor head was designed after detailed analysis demonstrated significant advantages for an angled sensor face. Lab tests showed that an angled head did the best job of shedding the bubbles that can form on the face of a sensor and give false turbidity readings. The angled head also allowed us to combine 90 degree backscatter sensing technology and our target sampling volume with a downward looking view, thereby significantly simplifying mounting and siting requirements.
The optical system, lens face and wiper blades have been designed for extended field life, even in high abrasive-load waters. After accelerated wear testing simulating five years of operation in abrasive enriched waters, wiper function remained within factory specifications and sensor readings were offset by only 2.9%, requiring only a simple recalibration.
The Digital Advantage
– On-board statistical functions
– Long cable runs without signal degradation
– Digital calibration is fast, simple, and accurate
– All calibration coefficients are stored in the sensor so datalogger reprogramming is not required when sensors are changed
– Compatible with all dataloggers that support the SDI-12 standard
– Constructed and Designed to Run 24/7 for many years
– All metal components are stainless steel or anodised aluminium and O ring sealed
– Extended duty cycle motor for many years of trouble free wiper operation
– Heavy duty miniature stainless steel universal joint for maximum life span
– Thick walled sensor housing designed to minimize damage from accidental blows or clamping pressure
– Depth rated to 98 feet
– Plastic components from Delrin or Noryl, selected for field proven durability, longevity, and thermal stability