Frequently Asked Questions: Dataloggers
What are dataloggers?
Dataloggers, which may also be referred to as Measurement and Control Units (Systems) or Microloggers, are the heart of a data acquisition system. They measure sensors at a specific scan rate, process data, store the data, and initiate telecommunications. Our dataloggers also have control capabilities allowing them to respond to specific site conditions by opening flood gates, turning fans off/on, etc.What is SDI-12?
The official definition of SDI-12 is Serial Data Interface at 1200 baud. Having stated that, SDI-12 is a protocol that was developed within the water resources field to make it easier to determine if a sensor and a datalogger were compatible. Instead of having to work through the specifications of the datalogger and the sensor for output, input, excitation, wiring, power, programming, etc., all SDI-12 sensors would have just three wires—a serial data line, a ground line, and a 12 Volt power line.Are your dataloggers Modbus compatible?
The CR510, CR500, CR10X, CR23X, CR800, CR850, CR3000, and CR1000 can be used for Modbus applications. The CR510, CR500, and CR10X require a special Operating System; Modbus protocol is standard in the CR23X, CR800, CR850, CR3000, and CR1000. If you already have a CR510, CR500, or CR10X and you want to use it for a Modbus application, you can purchase an operating system with the Modbus protocol and download it to the datalogger using CSOS downloading software or the DevConfig Utility.Can you describe about the data file that I retrieve from my datalogger? It is difficult for me to find what is what.
Let's start with a little background information. When you write the program with PC208W and save it, it asks if you want to compile the program. When you compile the program, PC208W creates four different files. One of the files that is created is the .fsl file. This is the final storage label file. It contains a list of labels for each of the numbers in your data. The files are saved in the same directory, which is typically your c: | pc208w or c: | program files | campbellsci | pc208w.
When the data is retrieved from the datalogger, most people save it as comma delimited. To make the data easier to read, you can use the fsl file to look at the data using VIEW in PC208W. You can also open the fsl file in Excel and transpose the list so that the labels are all in the top row. You can open the .dat file in Excel and tell the Open File wizard that it is a delimited file with commas as the separator. Insert a blank row at the top of the data and copy the labels to that blank row and go to File | Save As and give it a new name so that the original data file is not changed.
