The main components of a data acquisition (DAQ) system are the operator interface, the controller and the I/O. These systems used to be closed and proprietary, but they are now becoming more open to meet end user demands. Open systems allow users to mix and match components from different suppliers, with the assurance they will work well together.
Here are some of the primary benefits of open DAQ systems:
The best performing component can be selected for each function
Costs are reduced because many suppliers are competing in each component area
If one supplier stops producing a component, the end user can switch to an alternative
Specialized functions can be handled by components designed for the particular task
Closed and proprietary DAQ systems were favored by many suppliers because their customers were locked in, allowing them to raise prices, especially for spare and custom parts. But end users have forced these closed systems open and are now reaping the benefits.
A good example is PCI Express Cards, which can plug into any compatible bus and acquire data from a wide variety of sensors.