Data acquisition systems are used for large number of applications in industrial and scientific areas like aerospace and telemetry industries. Data acquisition system rapidly collects bulky of data, processing it and stores or displays the desired result.
The generalized block diagram of data acquisition system is shown in figure. It consists of sensors with signal conditioning, multiplexing, data conversion stage and display system.
Transducer converts physical parameters such as temperature, pressure, acceleration, weight, displacement, etc,. Into electrical quantities like voltage, resistance or frequency, which is an acceptable by the acquisition system. Signal conditioner modifies or amplifies transducer output signal. It includes circuits for providing excitation power to the transducer.
Multiplexer accepts multiple analog inputs and sequentially connects them to any one of the measuring instruments. ADC (analog to digital converter) converts the analog voltage to its equivalent digital form. Either ADC output is fed to any of the measuring devices or it may feed to digital computer for data reduction and further processing.