CS616

30 cm Water Content Reflectometer
CS616

CS616

Orderable

30 cm Water Content Reflectometer

Pricing

Sign in for pricing

Configuration

Sign in for option pricing

Select a configuration to add to your quote

Model:
CS616
Item Number:
45051
Warranty:
1 year

Overview

The CS616 measures the volumetric water content (VWC) of porous media (such as soil) from 0% to saturation. The probe outputs a megahertz oscillation frequency, which is scaled down and easily read by a Campbell Scientific data logger.

Key Advantages

High Accuracy and Precision
Designed for long-term monitoring

Technical Description

The CS616 is comprised of two 30-cm-long stainless-steel rods connected to the measurement electronics. The circuit board is encapsulated in epoxy, and a shielded four-conductor cable is connected to the circuit board to supply power, enable the probe, and monitor the output.

The CS616 uses the time-domain measurement method to measure VWC; a reflectometer (cable tester) such as the TDR200 is not required. This method consists of the CS616 generating an electromagnetic pulse. The elapsed travel time and pulse reflection are then measured and used to calculate soil volumetric water content.

Response Characteristics

The signal propagating along the parallel rods of the CS616 is attenuated by free ions in the soil solution and conductive constituents of the soil mineral fraction. In most applications, the attenuation is not enough to affect the CS616 response to changing water content, and the response is well described by the standard calibration. However, in soil with relatively high soil electrical conductivity levels, compacted soils, or soils with high clay content, the calibration should be adjusted for the specific medium. Guidance for making these adjustments is provided in the instruction manual.

Benefits

  • Compatible with most Campbell Scientific data loggers
  • High accuracy and high precision
  • Fast response time
  • Designed for long-term unattended water content monitoring
  • Compatible with AM16/32-series multiplexers, allowing measurement of multiple sensors
  • Probe rods can be inserted from the surface or buried at any orientation to the surface.

Specifications

Measurements Made
Volumetric water content (VWC) of porous media (such as soil)
Measurement Range
0% to saturation
Water Content Accuracy
±2.5% VWC

(using standard calibration with bulk EC of ≤ 0.5 dS m-1, bulk density of ≤ 1.55 g cm-3, and measurement range of 0% to 50% VWC)

Required Equipment
Measurement system
Soil Suitability
Long rods and lower frequency are well-suited for soft soil with low electrical conductivity (< 2 dS/m).
Rods
Not replaceable
Sensors
Not interchangeable
Operating Temperature Range
0° to +70°C
Probe-to-Probe Variability
±0.5% VWC in dry soil, ±1.5% VWC in typical saturated soil
Precision
Better than 0.1% VWC
Resolution
0.1% VWC
Output
±0.7 V square wave

(with frequency dependent on water content)

Current Drain
65 mA @ 12 Vdc

(when enabled)

45 μA

(quiescent typical)

Power Supply Voltage
5 Vdc minimum; 18 Vdc maximum
Enable Voltage
4 Vdc minimum; 18 Vdc maximum
Electromagnetic
CE compliant

(Meets EN61326 requirements for protection against electrostatic discharge.)

Rod Spacing
32 mm

(1.3 in.)

Rod Diameter
3.2 mm

(0.13 in.)

Rod Length
300 mm

(11.8 in.)

Probe Head Dimensions
85 x 63 x 18 mm

(3.3 x 2.5 x 0.7 in.)

Cable Weight
35 g per m

(0.38 oz per ft)

Weight
280 g

(9.9 oz) without cable

Similar Products

(4)

Compatibility

RF Considerations

The RF emissions are below FCC and EU limits as specified in EN61326 if the CS616 is enabled less than 0.6 ms, and measurements are made less frequently than once a second. External RF sources can also affect the CS616 operation. Consequently, the CS616 should be located away from significant sources of RF such as ac power lines and motors.

Installation Tool

The CS650G makes inserting soil-water sensors easier in dense or rocky soils. This tool can be hammered into the soil with force that might damage the sensor if the CS650G was not used. It makes pilot holes into which the rods of the sensors can then be inserted. It replaces both the 14383 and 14384.

Data Logger Considerations

The reflectometer connects directly to one of the data logger’s single-ended analog inputs. A data logger control port is typically used to enable the CS616 for the amount of time required to make the measurement. Data logger instructions convert the probe square-wave output to period which is converted to volumetric water content using a calibration.

Compatible Products

(2)

Incompatible Products

(2)

Related Resources

Case Studies

Documents

Showing 4 of 6 results

See all Documents

Videos and Tutorials