The pressure (gauge)/absolute pressure transmitter is a pressure signal measured at atmospheric pressure/vacuum as the reference end. Only one port is connected to the process pipe and the other end is connected to the atmosphere.
The working principle of the metal capacitive pressure (gauge pressure) / absolute pressure transmitter is that when the pressure acts indirectly through the isolating diaphragm and the pressure guiding medium on the surface of the metal measuring diaphragm (elastic measuring element) of different thickness, the diaphragm is produced. Tiny deformation, the maximum shape variable does not exceed 0.1mm, the high-precision circuit that measures the deformation of the diaphragm transforms this tiny deformation into a voltage signal proportional to the pressure, linearized, temperature compensated, and then uses a dedicated chip to apply this voltage signal. Convert to industry standard 4-20mA current signal or 1-5V voltage signal.
The high-sensitivity integrated circuit used in the high-sensitivity and measuring diaphragm detection circuit of the metal capacitive pressure sensor contains linear and temperature compensation circuits, so the entire transmitter can achieve high precision and high stability.
Metal Capacitive Pressure Sensors are extremely resistant to overload and excellent performance in micro pressure measurement, and are a must-have for a variety of complex industrial environments.
Technical performance
Use object: liquid, gas or steam
Measuring range: See selection specification sheet
Output signal: 4~20mA dc. Output, superimposed HART protocol digital signal (two-wire system)
Power supply: External power supply 24V dc., power supply range 12V ~ 45V
Load characteristics:
Hazardous location installation:
Explosion-proof ExdIIBT5Gb; (Explosion-proof certificate number: CE16.1163)
Intrinsically safe type ExiaIICT4/T5/T6Ga; (explosion proof number: CE15.2354X);
Migration features:
At the minimum range (40:1 range compression ratio), the maximum positive transition zero is 39/40 times the upper range limit.
The maximum negative transfer zero point can be the lower range limit and the absolute pressure transmitter has no negative transfer. (No matter the output form, after the positive and negative migration, the upper and lower limits of the range must not exceed the limit of the range)
temperature range:
The electronic circuit board works at: -40 to 85 ° C;
Sensitive components work at: -40 to 104 ° C;
Storage temperature: -40 ~ 85 ° C;
With digital display: -25 ~ 75 ° C (running);
-40 to 85 ° C (no damage);
Relative humidity: 0 to 95% (no condensation and frost)
Overpressure limit: Add 0 (absolute pressure) ~ 13MPa (or 1.5 times the upper limit of the range) pressure transmitter is not damaged; normal working pressure is from 0kPa (absolute pressure) to the upper limit of the range.
Volume change: less than 0.16cm3
Resistance: The time constant is adjustable from 0.2 to 32.0s.
Start-up time: 3s, no need to warm up.
Technical indicators
Accuracy: ±0.1%, ±0.075%
Stability: ±0.1%/12 months of the maximum range
Temperature effect: Temperature error including zero and span is ±0.2%/20°C of maximum range
Power supply effect: less than 0.005%/V of the output range.
Vibration effect: In any axial direction, the frequency is 200 Hz and the error is ±0.05%/g of the maximum range.
Load impact: As long as the input transmitter voltage is higher than 12V, there is no load influence in the load working area.
Installation position influence: The maximum zero error can be generated up to 0.25 kPa. This error can be eliminated by calibration, and has no effect on the range; the measurement body has no effect on the flange rotation.
(Unmigration, 316 stainless steel isolation diaphragm and other standard test conditions.)
Application and selection:
Ordinary pressure transmitter is the most commonly used measuring instrument in industrial process control. It is widely used in various automatic control systems, such as aerospace, military, petrochemical, chemical, oil well, electric power, shipbuilding, building materials, pipelines, etc. . Generally used in the measurement of the pressure or absolute pressure of liquid, gas or steam, the medium temperature is not too high, the corrosion is not strong, the viscosity is not high, and it is not easy to crystallize.
Selection note:
Before the user selects the type, the temperature, corrosiveness, measurement range, explosion-proof, whether it is explosion-proof, whether the oil is required to be processed or not, is required for the medium to be crystallized or viscous.
