Description
LDGRB-01 3BSE013177R1 A device that converts one standard signal to another standard instrument signal and/or performs some processing on that signal. Often called a converter, sometimes called a “relay”. Examples: I/P converter (converts a 4-20MA electrical signal to a 3-15psi pneumatic signal), P/I converter (converts a 3-15psi pneumatic signal to a 4-20mA electrical signal).
In general scientific terms, a “sensor” is a device that converts one form of energy into another, such as a microphone or thermocouple. However, in industrial instrumentation, we usually use the term “primary sensing element” to describe this concept, and reserve the term “transducer” to refer specifically to standard instrumentation signal conversion devices.
This device is capable of converting a signal generated by a Primary Sensing Element (PSE) into a standardized instrument signal, such as 3-15 psi barometric pressure, 4-20 mA DC current, fieldbus digital signal packages, etc., which can then be transmitted to an indicator. These signals can then be transmitted to an indicating device, a control device, or both.
Low and high range values, abbreviated as lrv and urv, respectively: Process measurements are considered to be 0% and 100% of the transmitter’s calibration range. For example, if a temperature transmitter is calibrated to measure a temperature range starting at 300 degrees Celsius and ending at 500 degrees Celsius, its level radiance will be 300 degrees Celsius and its level radiance 500 degrees Celsius.
LDGRB-01 3BSE013177R1 Alternative description of the LV and UR of the 0 and 100% points of an instrument’s calibration range.” Zero” refers to the starting point of an instrument’s range (equivalent to lv), while “span” refers to the width of its range (uv-lv). For example, if a temperature transmitter is calibrated to measure a temperature range starting at 300 degrees Celsius and ending at 500 degrees Celsius, its zero is 300 degrees and its span is 200 degrees.
A device that receives a process variable (PV) signal from a primary sensing element (PSE) or transmitter, compares that signal to a desired value (called a set point) for that process variable, and calculates the appropriate output signal value that will be sent to the final control element (FCE), such as a motor or control valve.
The controller can be a physical device or soft logic created in a PLC/DCS system. We mainly use PLC/DCS system soft logic controllers, where the actual input and output devices are connected to this soft controller.