Pressure Transmitters The Measuring Principle And Criteria
Pressure transmitters measure pressure when two pressures measured media into high and low pressure, δ elements (sensitive element) on both sides of the diaphragm, after isolation and components within the filled liquid transmit to measure both sides of the diaphragm. Measuring electrode and insulation film on both sides of the membrane form a capacitor.
When pressure differences on both sides, measure the displacement of the diaphragm, which is proportional to the displacement and pressure, so the capacitance range on both sides, after oscillating and demodulation process, converted the signals is proportional to the pressure. Pressure and absolute pressure transmitters the principle and differential pressure transmitters are the same, the difference is that low chamber pressure is the atmospheric pressure or vacuum.
A/d converters digital signal demodulator converts the current whose value is the microprocessor used to determine the input pressure. Microprocessor control transmitters work. In addition, it stops the linearization of sensor. Reset the measurement range. Engineering units conversion, damping, prescribe, and sensors to fine-tune operations, as well as diagnostics and digital communications.
This microprocessor with 16-byte applications in RAM, and three 16-bit counters, one performs a/d conversion. D/a converters to microprocessor and corrected digital signal tuning data, this data is made available transmitter software correction. Data is stored in EEPROM, also kept in good condition.
Digital communication lines provide a for the transmitter and external devices (such as the 275-control system of intelligent communication or using the HART protocol) interface interface. This line detection of superimposed digital signal 4-20mA signal and circuits required to transmit information.