Stevens - Model FTS DTS-12 - Turbidity Sensor
The DTS-12 is a turbidity and temperature sensor designed specifically to deliver high accuracy results from a sensor that can be easily field-deployed and requires very little maintenance. The sensor features a 12-month recalibration interval and a built-in silicon wiper blade which helps minimize biofouling, helping to ensure accurate sampling from 0 to 1,600 NTU. The DTS-12 meets the quality standards of the USGS and has received their approval for in-situ turbidity monitoring.
In order to provide quality turbidity data, the DTS-12 takes 100 readings over five seconds, then computes and outputs the mean, variance, median, min, and max values. This statistical analysis compensates for entrained debris spikes and “cleans” the data, providing a precise measurement of bulk turbidity.
The DTS-12 uses Nephelometric geometry calculations to improve the signal-to-noise ratio by measuring the forward and back scattered light at a 90° angle to the light beam. Because of Nephelometry’s sensitivity, precision and applicability over a wide particle size and turbidity range, it’s the preferred method for measuring turbidity by the EPA.
The DTS-12 is simple to configure and use, offering a standard SDI-12 output for communication with data loggers or telemetry devices.
The housing and all metal hardware is made from marine-grade stainless steel, so it's suitable for freshwater and saltwater applications.
- Measures temperature as well as turbidity
- O-ring sealed for effective watertight security
- Heavy-duty waterblock cable
- Extended duty cycle wiper motor for years of service
- Durable stainless steel universal joint for wiper mechanism
- Thick-walled aluminum shell
Two cavities on either side of optic face allow debris to be flushed away from the wiper between wipes, and the top edge scrapes away any stubborn fouling from the wiper blade. The wiper also “parks” in one, which extends the flexibility of the wiper blade.
Angled head sheds bubbles that can form on the optic face and give false turbidity readings. It provides the ideal Nephelometric geometry for excellent accuracy across the full range. It also simplifies mounting and siting in shallow locations.
Non-abrasive silicone wiper blade is designed for long-term deployment and eliminates optical face abrasion even in highly abrasive sediment-rich waters.
Optical face is made from Noryl and Delrin, selected for their field-proven durability and thermal stability. Large optic lenses virtually eliminate scratch induced measurement bias.
Optional quick disconnect cable connectors allow rapid on-site servicing and instrument swap.
Marine-grade stainless steel housing make the DTS-12 suitable for long-term saltwater or brackish water deployments.
- Sensor type : Turbidity: Optical nephelometer (sidescatter)
- Temperature: Encapsulated thermistor
- Range : 0 to 1,600 NTU (nominal)
- Accuracy : Turbidity: ±2% of reading + 0.2 NTU (0-399 NTU), ±4% of reading (400-1,600 NTU) (@ 25°C)
- Temperature: ±0.2 °C
- Resolution : Turbidity: 0.01 NTU
- Temperature coefficient :
- Supply voltage range : 9.6V to 16V
- Current consumption
- (typical): : Standby: 0.35 mA
- Operating: 50 mA
- Motor wiping: 200 mA
- Depth rating : 98 ft. (30m)
- Wipe time : 5 seconds (nominal)
- Operating temperature : +32 °F to +104 °F (0 °C to +40 °C)
- protocol : SDI-12, version 1.3
- Measurements returned : Instantaneous turbidity, from 100 samples taken, the following are computed: Mean, Variance, Median, BES, Min, Max, Temperature
- Sample rate : 20 Hz
- Dimensions : 12 in. (30.48 cm) x 2 in. (5.08 cm)
- Weight : 23.3 oz (604 g)