Turbidity Meter, Turbidimeter - TurbSense®

The turbidity meter from Pi is the world’s only probe based turbidity meter with a resolution of 0.001NTU. It achieves this through its patented technology that complies with international standard ISO 7027 at the same time that it sets the standard in stability and low maintenance.

The patent relates to the measurement of the emitted light as well as the received light allowing the TurbSense® turbidimeter to vary the light output. Doing this allows for the mathematical correction for zero, zero drift, aging optics and fouling windows. The TurbSense® self-calibrates every time it takes a reading and therefore it is only necessary to check the calibration every several months.

DocumentTypeSize
TurbSense®Brochure631kB
TurbSense® CalibrationArticle942kB
TurbSense® Secondary StandardsTechnical Note676kB
TurbSense® Mounting OptionsTechnical Note948kB
US Turbidity TrialArticle924kB
Bubbles in TurbidityTechnical Note584kB
Overcoming ‘Noise’ and Establishing a ‘Zero’Technical Note677kB
Secondary Standards InstructionsTechnical Note563kB
Probe FoulingTechnical Note459kB
 

FAQs

Turbidity uses nephelometric turbidity units (NTU) and is a measurement of the ‘cloudiness’ of a water sample. Suspended solids describes the mass of solid particles suspended in a given volume of water and is most commonly expressed in mg/l. The two measurements are related, but the conversion between them will depend upon the properties of the suspended material.
TurbSense® can be calibrated in three ways. Firstly, a separate device (commonly a hand held, portable turbidimeter) can be used to analyze the same sample as the TurbSense® and this value can be used to perform the calibration. Secondly, the sensor can be placed into a sample of known turbidity (such as a 25 NTU standard solution), and the TurbSense® system can calibrate itself based on this. Because of the unique way in which the sensor performs the calibration, only a single standard is required and a zero point calibration isn’t needed (patented feature). Thirdly, solid secondary calibration standards (available from Pi and its partners) provide a solid that when put against the end of the TurbSense® provides a known response that can be used to either check or calibrate a TurbSense®
Compared to glass or quartz, sapphire is much tougher and resistant to scratches. Additionally, because it is much stronger the window can be thinner, which improves the quality of optical transmission.

Yes, 50°C or 120°F. This is because the electronics inside the TurbSense® will start to degrade in temperatures higher than that.

Turbidity in water is a measure of how cloudy the water is, and is used in making clean water for people to drink.

Yes, but there are factors end users should consider because the reliable operation of the sensor depends upon a powerful light source and sensitive optics. Reflections from walls and bends in pipes can cause problems in accuracy, so the turbidity of the process stream, the diameter of the pipe and the material used will need to be taken into account.

Larger diameter pipes and those made of less reflective materials are better; additionally, the higher the turbidity the more likely pipe insertion will be effective. At >200NTU, putting a TurbSense® into a pipe shouldn’t be a problem.

Many users who purchase TurbSense® use our AutoClean option to ensure optimum performance; pressurized water cleans the sensor head on a user designed schedule which greatly reduces maintenance times. Ideally the sensor should not be placed in direct sunlight as this can affect the reliability of the sensor.

The specially designed flow chamber provides the ideal environment for the TurbSense®. It removes entrained bubbles, is sealed against ambient light and its black polypropylene construction eliminates internal reflections. It also allows the sensor to be incorporated into a sample line along with other sensors.

For samples with no nucleating or entrained bubbles and an atmospheric drain.

For samples with entrained air and with an atmospheric drain.

For samples with nucleating bubbles (air coming out of solution) or if no atmospheric pressure drain is available

For direct insertion into a pipe.

For mounting the TurbSense® on the end of a pole and dipping it into a tank or body of water.

For mounting the TurbSense® on the end of a pole and dipping it into a tank or body of water when the turbidity is low and sunlight could affect the readings.

A solid calibration standard to check the TurbSense® readings or to be used as a calibration. Available in 0.9 NTU and 18 NTU.

Options

Downloads