CR300 series data acquisition system components

A basic data acquisition system consists of sensors, measurement hardware, and a computer with programmable software. The objective of a data acquisition system should be high accuracy The degree to which the result of a measurement, calculation, or specification conforms to the correct value or a standard., high precision The amount of agreement between repeated measurements of the same quantity (AKA repeatability)., and resolution The smallest interval measurable. as high as appropriate for a given application.

The components of a basic data acquisition system are shown in the following figure.

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Following is a list of typical data acquisition system components:

• Sensors - Electronic sensors convert the state of a phenomenon to an electrical signal (see Sensors for more information).

• Data logger - The data logger measures electrical signals or reads serial characters. It converts the measurement or reading to engineering units, performs calculations, and reduces data to statistical values. Data is stored in memory to await transfer to a computer by way of an external storage device or a communications link.

• Data Retrieval and Communications - Data is copied (not moved) from the data logger, usually to a computer, by one or more methods using data logger support software. Most communications options are bi-directional, which allows programs and settings to be sent to the data logger. For more information, see Sending a program to the data logger.

• Datalogger Support Software LoggerNet, RTDAQ, and PC400 - these Campbell Scientific software applications include at least the following functions: data logger communications, downloading programs, clock setting, and retrieval of measurement data. - Software retrieves data, sends programs, and sets settings. The software manages the communications link and has options for data display.

• Programmable Logic Control - Some data acquisition systems require the control of external devices to facilitate a measurement or to control a device based on measurements. This data logger is adept at programmable logic control. See Programmable logic control for more information.