Pressure Transmitters, a sub-group of pressure transducers, feature additional reset and calibration options. With some sensor types it is possible, for example, to re-set the measuring span over large ranges. This calibration option is usually referred to by such terms as “scale down”, “span reset” or “turn down”. For instance, a transmitter with a measuring range of 0 to 400 psi and a range reset 1/10 can be calibrate to a measuring range of 0 - 40 psi while still giving a full output signal (4 - 20 mA, for example).
It is also possible to shift the zero point over a wide range and to calibrate the damping of the output signal between 0 and 32 seconds. Smart transmitters such as Hart®, which also have logging capabilities, can be calibrated, tested and reset via the control desk or hand terminals.
Transmitters are often used in process applications where they can be combined with various chemical seals.