Temperature salt depth meterThe measurement accuracy varies depending on the model and sensor type, and the following are the measurement accuracy ranges for its core parameters:

1、 Temperature measurement accuracy

High precision model: ± 0.001 ℃ to ± 0.002 ℃

For example, the temperature accuracy of the Dawan DW16 series and HD16 high-precision temperature and salinity depth measuring instruments is ± 0.002 ℃, with a resolution of 0.0001 ℃.

**Environmental adaptability: Some models can maintain normal operation in a low temperature environment of -5 ℃, and the temperature stability is better than 0.0002 ℃ per month.

Universal model: ± 0.003 ℃ to ± 0.005 ℃

For example, the temperature accuracy of RBRconcerto CTD in Canada is<0.0005 ℃, the time constant is<95ms, and the drift is<0.002 ℃/year.

2、 Conductivity measurement accuracy

High precision model: ± 0.003mS/cm to ± 0.005mS/cm

For example, the electromagnetic conductivity accuracy of the Dawan DW16 series is ± 0.005mS/cm, the electrode type is ± 0.003mS/cm, and the resolution is 0.0001mS/cm.

Special design: Hydrocat CTD adopts the quartz conductivity cell three electrode method to avoid edge effects and ensure data accuracy.

Universal model: ± 0.007mS/cm to ± 0.01mS/cm

For example, the conductivity accuracy of Idronaut Ocean Seven304 in Italy is 0.007mS/cm, with a resolution of 0.001mS/cm.

3、 Accuracy of pressure (depth) measurement

High precision model: ± 0.015% to ± 0.05% full scale (FS)

For example, the pressure accuracy of the Dawan DW16 series is ± 0.05% FS, the resolution is 0.002% FS, and the drift is 0.05% FS/year.

Deepwater capability: Some models can withstand pressure water up to 7200 meters deep (such as DW1613-D), meeting the needs of deep-sea observation.

Universal model: ± 0.05% FS to ± 0.1% FS

For example, the pressure accuracy of the German Sea&Sun Technology CTD48M is 0.002% FS, with a measurement range of 0-6000 bar.

4、 Salinity measurement accuracy

Calculation accuracy: ± 0.002PSU to ± 0.1PSU

Salinity data is calculated from parameters such as temperature and conductivity, and is therefore affected by sensor accuracy.

For example, the salinity accuracy of RBRconcerto CTD in Canada reaches 0.002PSU, which can be used as a substitute for sonic instruments; The salinity accuracy of Star Oddi micro CTD is ± 1.5PSU (when the conductivity range is 13-63mS/cm).

5、 Other parameter accuracy (extended functionality)

Dissolved oxygen: ± 2% saturation (such as temperature salt depth comprehensive measurement system)

PH value: ± 0.05pH (such as German Sea&Sun Technology CTD60M)

Sound velocity: ± 0.01m/s to ± 0.1m/s (calculated from temperature, salinity, and pressure)