Not every sensor comes with a calibration sheet. If a calibration sheet is included, it is listed in the “Ships With” section of the sensor’s product web page or it is specified when ordered.
Whenever possible, purchase a sensor with the desired cable length. Some sensors have a user-specified cable length, whereas other sensors have a set cable length.
Sometimes, an old cable can be replaced with a new, longer cable.
Generally, additional cable cannot be spliced onto the existing cable because:
- Some sensor cables have bridge completion resistors at the pigtail end
- Some sensors are calibrated based on cable length
- Sometimes the color in the insulation is not the same as that visible at the pigtail end
- It is possible to introduce errors or malfunctions depending on the integrity of the splice
Splicing cable together increases the likelihood that water may enter the cable and cause shorting, corrosion, and some other potential problems, which in turn can cause measurement problems.
Because of the potential problems, do not splice any sensor cable without first contacting an application engineer at Campbell Scientific to discuss the sensor in detail.
Sometimes, an old cable can be replaced with a new, shorter cable.
Sometimes, an existing cable can be shortened by cutting the ends off. However, there are a few problems that could be encountered when doing this:
- Some sensors have bridge completion resistors at the pigtail end.
- Some sensors are calibrated to length.
- Sometimes the color in the insulation may not be the same as that visible at the pigtail end.
Because of the potential problems, do not cut the ends off of any sensor cable without first contacting an application engineer at Campbell Scientific to discuss the sensor in detail.
Many times, but not always, a sensor’s cable can be replaced with a new cable. This is helpful if the original cable was damaged or if its length needs to be changed.
If the cable is attached to the sensor using a connector, Campbell Scientific will sell a replacement cable. For example, a 05106CBL-L is a replacement cable for a 05106-L. Replacement cables are listed in the “Replacement Parts” section of the Ordering tab of the product page.
If the cable is attached to a sensor through a user-accessible terminal block, a raw cable can be purchased to replace it. For example, to replace the cable on a 05103-L Wind Monitor, order the desired length of 24 AWG 3 Twisted Pair Shielded Santoprene® Cable (pn 9721). As another example, the raw cable for a TE525-L Rain Gage is pn 9661 (22 AWG 1 Twisted Pair Shielded Santoprene® Cable).
If the cable is an integral part of the sensor, the cable cannot be user replaced, and the sensor must be returned to Campbell Scientific. Some examples of sensors that fall into this category include the 107-L, 109SS-L, 229-L, CS547A-L, and CS650-L. Refer to the Repair and Calibration page for the process of returning equipment to Campbell Scientific.
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About Infrared Gas Analyzers
Campbell Scientific offers both open-path and closed-path infrared gas analyzers that measure carbon dioxide, water vapor, temperature, and pressure. These analyzers feature aerodynamic designs to minimize wind distortion and low power dissipation to minimize error caused by analyzer body heating.
The EC150 (open-path) and EC155 (closed-path) gas analyzers can be configured with CSAT3A sonic anemometer sensor heads to create eddy-covariance flux systems. The sonic anemometer mounts closely beside the gas analyzer to minimize error caused by spatial separation of the gas and wind measurements. The gas analyzer and sonic anemometer also share common electronics—reducing cost, simplifying installation, and providing time synchronization between the sonic and gas measurements.
The IRGASON provides the ultimate integration of gas and wind measurements - one sensor that measures CO2, H2O, three-dimensional wind velocity, and sonic temperature in the same place at the same time. This level of integration has been unavailable in previous eddy-covariance systems.