The CS547A is a water quality probe that measures both electrical conductivity (EC) and temperature. It connects to a Campbell Scientific datalogger via the A547 interface. This probe is compatible with most Campbell Scientific dataloggers.Read More
The CS547A-L requires the use of an A547, which is purchased separately. The A547 contains blocking capacitors and bridge completion resistors necessary for measurement of the CS547A-L.
The "-L" on a product model indicates that the cable length is specified at the time of order.
The CS547A measures temperature with a thermistor. Electrical conductivity (EC) is measured with three cylindrical stainless-steel electrodes mounted in an epoxy housing. The electrode configuration eliminates ground loop problems associated with sensors in electrical contact with earth ground. The electrodes are ac coupled, and the datalogger applies a bipolar excitation. This process reduces electrochemical reactions, minimizes corrosion, and extends the probe’s life.
The CS547A is easy to clean and resistant to corrosion. It has rounded ends to facilitate installation and removal. The CS547A is shipped with a cell constant calibrated in a 0.01 molal KCl solution at 25°C. The solution has an EC of 1.408 mS cm-1.
|Conductivity Measurement Range||~0.005 to 7 mS/cm|
|Temperature Measurement Range||0° to 50°C|
|Temperature Polynomial Linearization Error||Typically < 0.1°C (over 0° to 48°C)|
|Thermistor Interchangeability||Typically < 0.2°C (over 0° to 50°C)|
|Wetted Materials||Epoxy housing, 316 stainless-steel rings, polyurethane cable|
|pH Operating Range||Solution pH of less than 3.0 or greater than 9.0 may damage the stainless-steel housing.|
|Operating Temperature Range||-15° to +50°C|
|Depth Rating||305 m (1000 ft) maximum|
|Weighted Cable Weight||80 g (2.8 oz)|
The minimum pipe ID that the CS547A-L fits is 2.79 cm (1.1 in.).
The A547 Interface is required for connecting the probe to the datalogger. This interface contains the blocking capacitors and bridge completion resistors necessary for the conductivity measurement.
A 3-ft cable is shipped with the sensor to connect the A547 to the datalogger terminals. The CS547A requires one differential analog input, one single-ended analog input, and two excitation channels. One excitation channel must be capable of delivering ac excitation, so the BDR301 or BDR320 are NOT compatible.
Special considerations apply when two or more CS547A probes will be measured by a single datalogger.
A CR510 cannot be used to measure two probes because it does not provide sufficient (three) excitation channels.
Although it is acceptable for the two thermistors to share an excitation channel, each conductivity measurement requires a dedicated excitation channel. If excitation for the conductivity measurement were to be shared from a common excitation channel, both solutions would become polarized and once excitation was removed, some charge could be transferred from one solution to the other making the measurements interdependent on one another. If more than two CS547A probes are to be measured, then an AM16/32-series multiplexer is required.
|CR200(X) Series||CR800/CR850||CR1000||CR3000||CR9000X||CR6 Series||CR300 Series|
*The CR500 and CR510 can not measure more than one CS547A probe because they do not provide enough excitation channels to measure more probes.
**The CS547A-L is NOT compatible with CR300-series dataloggers. The released version of ShortCut (SCWin) incorrectly indicates that they are compatible, but they are not.
If more than two CS547A probes are to be measured, then an AM16/32-series multiplexer is required. In this scenario, each probe is wired to the multiplexer and one A547 interface is wired between the multiplexer and the datalogger. If the system were maximized, up to sixteen CS547As could be connected to the multiplexer. However, because the A547 becomes a part of the measurement circuit for all connections to the multiplexer, only CS547A probes could be connected to the multiplexer (i.e., it is not possible to mix other sensor types with the CS547As attached to the multiplexer).
Number of FAQs related to CS547A-L: 18
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The readings will be accurate for the sample of water inside the cavity, but that may or may not be indicative of the overall conductivity of the well. Flowing water allows a more representative measurement over time.
Position the CS547A-L so that it is protected during high flow but remains submerged at base flow. Orient the measurement cavity parallel to the water flow.
Ice forming inside the hollow cavity can damage the sensor; therefore, as a precaution, the sensor should be removed.
An analog voltage signal of no more than 2500 mVdc.
Exciting the CS547A-L with an electrical charge to make a measurement causes ionization. The ionization correction code corrects for this disruption.
The sensor should never need recalibration under normal use unless the diameter of the measurement cavity changes because of corrosion or abrasion. For more information, refer to the “Factory Calibration” and “Field Calibration” sections of the CS547A instruction manual.
This sensor is designed for freshwater applications and should not be used in seawater.
If the measurement cavity is kept clean, ephemeral conditions should not affect the reading.