Data acquisition is the process of sampling signals that measure real world physical conditions and converting the resulting samples into digital numeric values that can be manipulated by a computer. Data acquisition systems (abbreviated with the acronym DAS or DAQ) typically convert analog waveforms into digital values for processing. The components of data acquisition systems include:
* Sensors that convert physical parameters to electrical signals.
* Signal conditioning circuitry to convert sensor signals into a form that can be converted to digital values.
* Analog-to-digital converters, which convert conditioned sensor signals to digital values.
Data acquisition applications are controlled by software programs developed using various general purpose programming languages such as BASIC, C, Fortran, Java, Lisp, Pascal. COMEDI is an open source API (application program Interface) used by applications to access and control the data acquisition hardware. Using COMEDI allows the same programs to run on different operating systems, like Linux and Windows.
Communication features include fast serial data transfers at up to 19,200 baud. The software supports any number of remote dial-up stations (XR440 Data Loggers equipped with modems) and up to 255 wireless links. Hardwired network operation (up to 255 loggers per network) is also supported.
Data is viewed graphically in up to four viewports. Channel data traces can be combined into a single viewport or separated as desired. Zooming is controlled by dragging the mouse over a section of the graph. Pointing the mouse at any data point displays its time stamp and value. The user can modify colors, traces displayed, trace attributes and much more. Temperatures can be displayed in Celsius or Fahrenheit.
A standard for serial communications found in many data acquistion systems. RS232 is the most common serial communication, however, it is somewhat limited in that it only supports communication to one device connected to the bus at a time and it only supports transmission distances up to 50 feet.
A standard for serial communications found in many data acquistion systems. RS485 is not as popular as RS232, however, it is more flexible in that it supports communication to more than one device on the bus at a time and supports transmission distances of approximately 5,000 feet.
The Industrial Ethernet IO systems can be used for data acquisition, machine monitoring and process control.
Either as a stand-alone system or controlled from a remote computer, data can be acquired, processed, stored and shared over the network.