The CS625 measures the volumetric water content from 0% to saturation. It is similar to our CS616 but is designed specifically for CR200(X) and CR300-series dataloggers. This reflectometer has a 0 to 3.3 V square wave frequency output that our CR300-series and CR200(X)-series dataloggers can measure.Read More
|Measurements Made||Volumetric water content of porous media (such as soil)|
|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).|
|Operating Temperature Range||0° to 70°C|
|Probe-to-Probe Variability||±0.5% VWC in dry soil, ±1.5% VWC in typical saturated soil|
|Output||0 to 3.3 V square wave (with frequency dependent on water content)|
|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|
Please note: The following shows notable compatibility information. It is not a comprehensive list of all compatible products.
The RF emissions are below FCC and EU limits as specified in EN61326 if the CS625 is enabled less than 0.6 ms, and measurements are made less frequently than once a second. External RF sources can also affect the CS625 operation. Consequently, the CS625 should be located away from significant sources of RF such as ac power lines and motors.
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 were not used. It makes pilot holes into which the rods of the sensors can then be inserted. It replaces both the 14383 and 14384.
Each CS625 requires a single-ended input channel. A control port is used to enable one or more probes.
Note: A maximum of four CS625 probes can be measured by one CR200(X) datalogger. Valid channel options are analog channels 1 through 4.
Number of FAQs related to CS625: 34
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300 m (1,000 ft).
Yes, as long as the data logger can detect a 0 to 3300 mV square wave over a frequency range of 29 to 67 kHz.
No. The output is too fast to be measured on the pulse channel of a 21X or CR7.
If the new site has soil with a different soil type, a soil-specific calibration may be needed. For soil that is sandy or sandy loam with low bulk electrical conductivity, the calibration equation in the CS616 and CS625 instruction manual works well.
The CS616 and CS625 are water-content reflectometers with measurement electronics built into the probe head. The electronics generate a signal, which is sent directly to the data logger. The CS610-L, and other three-rod probes sold by Campbell Scientific, are TDR probes that have no electronic components and serve as wave guides for a time-domain reflectometer such as the TDR100.
Yes. The PeriodAvg() CRBasic instruction may be used to measure the CS625 on a CR1000, CR800-series, or CR3000 datalogger. To make this work, it is important that the Threshold parameter be set to 1650 mV as shown in the following example:
PortSet (1 ,1 ) ‘Enable CS625 by setting C1 high (orange wire to C1)
PeriodAvg (PA_uS,1,mV250,1,1650,0,100,10,1.0,0) ‘Read Period on SE1 (green wire to SE1)
PortSet (1 ,0) ‘Disable CS625 by setting C1 low
Running the cable through electrical conduit or PVC pipe will protect the cable from rodents. A trench 30 to 60 cm deep will protect it from most other human or animal activity. Some customers have found that extra cable can be coiled and left inside a box, such as an irrigation valve box or something similar. When using a box, seal any holes that are large enough for rodents to enter. When cables are exposed on the ground surface, some customers have found that wrapping the cables in the metal screening used for screen doors discourages animals from chewing on them.
If a soil-specific calibration is performed, the CS616/CS625 may be used in soil with a maximum bulk electrical conductivity of 5 dS/m.
If the electrical conductivity within the waste is less than 5 dS/m and there is good contact between the probe rods and the waste, the CS616/CS625 should respond predictably to changes in water content. The heterogeneous nature and changing bulk density of solid waste, however, make calibration difficult.