Hydrocat CTD is a water quality meter dedicated to long-term online monitoring. Mainly used for long-term online observation of biogeochemical parameters in coastal ecosystems (long-term online monitoring for up to one year). Measurement parameters include temperature, conductivity, pressure, salinity, depth, dissolved oxygen.
Application field
It can be used for long-term sequence measurement of seawater temperature, conductivity, salinity, pressure, dissolved oxygen and other parameters (anchorage system), and can also be used for portable observation. The measurement of water bodies includes:
Coastal waters
Estuary bay
Lakes and reservoirs
Rivers and streams
Performance characteristics and advantages
Excellent anti-fouling performance
(1) Measurement method—temperature, conductivity, dissolved oxygen and other parameters are in a relatively closed pipeline. During the measurement, the water body is controlled by a water pump to enter the pipeline at a constant flow rate to complete the measurement. Because there is no light in the pipeline, it is difficult for organisms to grow, so it can effectively prevent the influence of organisms on the data. Hydrocat CTD's external biological pollution after long-term deployment in harsh environments shows that the probe inside the instrument is still in good condition when the external pollution of the instrument is serious.
(2) Anti-pollution situation of the conductivity probe-the conductivity probe is made of quartz glass, the inner wall is smooth, and it is difficult to adsorb pollutants; the water pump is turned on every measurement, and the water to be measured flows through the conductivity cell at a constant flow rate Conductance probe for cleaning.
(3) Anti-biological pollution kit-equipped with anti-biological pollution accessories approved by the US EPA, which can prevent the growth of life.
Accurate-high accuracy and low drift rate
(1) Response time and accuracy of salinity data ---- Salinity data is calculated from multiple parameters such as temperature and conductivity, so the slight error of each parameter may have a huge impact on the measurement results. Hydrocat CTD uses a pump to control the water sample to pass through each sensor at a constant flow rate. On the one hand, it can ensure that each sensor measures the same water body. On the other hand, the water sample to be measured is updated at a constant flow rate in real time, thereby ensuring that each sensor Have the same response time.
(2) The effect of edge effects on salinity data-conductivity measurement methods include electrode method and induction method. Using inductive measurement method, the measurement data is greatly affected by the surrounding environment. For example, there are metal substances around the probe, which will have a greater impact on the measurement results, and the degree of influence is related to the position of the metal substance, and the effect of edge effects on the data The degree is difficult to assess. Hydrocat CTD adopts the three-electrode method of quartz conductivity cell independently developed by Sea-bird Scientific, which can accurately measure the conductivity without being affected by the edge effect.
Cost-effective-no on-site calibration is required, and a typical delivery cycle of more than three months reduces on-site maintenance costs.
Other features
All meters are calibrated at the factory through the temperature control calibration slot, the accuracy of the temperature control calibration slot is 2 – 4 times the accuracy of the meter.
