A PA device has at least 3 function blocks. What are these blocks and what is their purpose?
In the process industry it is common to use blocks to describe the characteristics and functions of a measuring/manipulation point and to represent an application through a combination of these blocks. The specification of PA devices uses this function block model to present functional sequences.Physical Block (PB)Describes the necessary parameters and functions of the device itself (e.g. software version, serial number, vendor ID, factory reset command). There is only one Physical block in a PA device.Transducer Block (TB)Contains parameters which have effect or describe the type of sensor or actuator. Transducer blocks may also contain parameters for calibration and linearization. The processed information is passed on to the Function Block. If a device has more sensors, it has corresponding Transducer Blocks for every sensor.Function Block (FB)Contains one or more cyclically accessible inputs or outputs parameters (process values). These can be of analog or discrete nature.