The task of transmitters is the transformation of the sensor signal into a stable and standardized signal. In the past, transmitters were built using analog technology. In the meantime digital technology has gained acceptance, however, because it offers better measurement accuracy at simultaneously higher flexibility, improve safety and safe costs.
In addition, the measurement accuracy in modern transmitters can be improved by use 'sensor-transmittermatching'. The complete measurement point can be calibrated in a loop (Sensor and transmitter together).
On the one hand, the standardized output signal in the process measurement is a 4...20 mA signal, but also the internationally standardized field buses, such as HART®, PROFIBUS® and FOUNDATION™ Fieldbus are used. The HART® protocol serves mainly for a more convenient operation in combination with the 4...20 mA analog measured signal. PROFIBUS® and FOUNDATION™ Fieldbus, however, transfer the real measured value digitally without any loss of accuracy and therefore offer cost savings by simplifying the wiring.
TMT85
