HYDROS 21 Conductivity Temperature & Depth Sensor

The case of too many sensors

The problem with most water level, temperature and depth sensors is that their cost is prohibitively high. Not only that, but the measurement often requires you to purchase an extra sensor to make a barometric pressure reading to correct for atmospheric pressure. You need a low-cost instrument that's equipped with every sensor necessary for things like tracking changes in solute movement, measuring groundwater recharge and studying surface water hydrology. You need the HYDROS 21.

Just the right mix of measurements

A compact 3.4 cm diameter sensor that fits into tight spaces, the HYDROS 21 is a low-cost, durable, and easy-to-use tool for monitoring EC, temperature, and depth in both groundwater and surface water. More importantly, it's an all-in-one instrument. When used with our ZL6 Data-logger, you won't require an additional sensor for determining-and correcting for-barometric pressure. With a range of 0 to 120 dS/m and a measuring depth of 10 m, the sensor makes accurate EC measurements for a broad range of applications.

Level 1 simplicity (on a scale of 1-10)

One of the qualities that makes the HYDROS 21 so easy to use is its fast plug-and-play compatibility with the ZL6 Data-logger (also compatible with Campbell Scientific data loggers). Plus, with the ZL6 Data-logger, you can monitor and remotely access data wirelessly from any internet-connected computer in near-real time.

Same measurement specs for less

Trying to measure water level, temperature, and EC typically requires an expensive sensor (especially one that measures EC). Since much of the HYDROS 21's complex circuitry is in the data logger, the cost of each individual sensor is lower. So instead of having to rely on a single point measurement, you can now take readings in several different locations without exceeding your budget.

A high-level water sensor in every sense

While engineering the HYDROS 21, we wanted to design a water level sensor that was not only highly accurate but also provided a high degree of value. Because of its low-complexity, low-maintenance and low-cost design, you can be assured you're getting an instrument that will save you time, hassle and money.

Range: 0 to 10 m
Conductivity 0 to 120 dS/m (mS/ cm)
Temp -11 to +49ºC
Accuracy: Depth: + 0.25% of full scale @ 20°C
Conductivity+ 0.01 dS/m or + 10% (whichever is greater)
Temp+/- 1ºC
Depth 1mm
Conductivity 0.001 dS/m
Temp 0.1ºC
Operating Temperature:
0 to 60°C
Power Requirements: 3.6 - 15 VDC, 0.03 mA quiescent, 0.5 mA during 300 ms measurement
Dimensions: Housing: 3.4 cm Diameter, 9 cm length
Output: Serial TTL, 3.6 Volts Levels or SDI-12
Cable Length: 10m standard; custom lengths available upon request
Measurement Time: 300 ms
Data Logger Compatibility (not exclusive) METER: ZL6 & ProCheck
Other: Any data acquisition system capable of 3.6-15V excitation and serial or SDI-12 communication
Warranty One year, parts and labour

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Labcell Limited exclusively supply and support METER products in the UK & Ireland.

Non UK/Ireland Customers, please contact METER Environment at:www.metergroup.com/environment/


HYDROS-21 Cable


  • Continuously monitor groundwater and surface water level changes
  • Integrated electrical conductivity and temperature measurement
  • 3.4 cm diameter sensor that fits into tight spaces
  • Low cost
  • Durable
  • Easy to use

METER Soil Lab
Size: 1.3 MB (1,314,079 bytes)

Quotation Request

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