Differential pressure transmitters are widely used instruments in industrial production, measuring various physical parameters such as pressure, level, and flow rate, which are crucial for industrial operations.
Differential pressure transmitters measure the pressure difference of media in process pipelines or tanks, converting the measured differential pressure value into a current signal output through data conversion and square root extraction. However, when selecting a differential pressure transmitter, attention must be paid to parameters such as the differential pressure value and the medium. Furthermore, the following issues should be considered when operating a differential pressure transmitter:
1. The equipment site environment is often harsh. Strong electrical signals can generate various types of electromagnetic interference, and lightning surges can produce strong pulses. In such situations, a challenging problem for microcontroller applications is how to reliably transmit small signals over long distances in harsh environments. Considering that the high-frequency noise of the transmitter is mainly coupled by the parasitic capacitance between the primary and secondary windings of the transformer, not by the mutual inductance of the primary and secondary coils, a shielding layer is used to isolate the primary and secondary windings of the isolation transformer, reducing its distributed capacitance and improving its resistance to common-mode interference.
2. However, in situations requiring long-distance signal transmission or operating in environments with significant power grid interference, the use of voltage output sensors is severely limited. This is due to their poor anti-interference capability and the impact of line damage on accuracy. Two-wire current output transmitters, on the other hand, are widely used due to their extremely high anti-interference capability.
3. The concentration of acid and alkali solutions is proportional to their conductivity. Therefore, by measuring the conductivity of the solution, the concentration of acid or alkali can be determined. When the solution flows into a dedicated conductivity cell, if electrode polarization and distributed capacitance are ignored, it can be considered equivalent to a pure resistor. When a constant voltage alternating current flows through it, the output current is linearly related to the conductivity, which in turn is proportional to the concentration of acid or alkali in the solution. Therefore, by measuring the solution current, the concentration of acid, alkali, or salt can be calculated.
4. This type of fault requires replacement of the amplifier board. Transmitters have very strict requirements in terms of circuit design and assembly quality. In actual use, if a circuit fault occurs, after inspection and confirmation, it is best to contact the manufacturer to replace the faulty circuit board to ensure the long-term stability and reliability of the instrument.
5. The Influence of Installation Position on Zero Output of Micro Differential Pressure Transmitters: Due to the very small measurement range of micro differential pressure transmitters, the weight of the sensing element itself will affect the output. Therefore, zero-point changes during installation are normal. During installation, the pressure-sensitive element of the transmitter should be perpendicular to the direction of gravity. If installation conditions are limited, the transmitter's zero point should be adjusted to the standard value after installation and fixation.
6. We know that regardless of the model, differential pressure transmitters have vent and drain valves or stopcocks in both the positive and negative pressure chambers. This facilitates on-site calibration of differential pressure transmitters, meaning that the transmitter can be calibrated without removing the pressure lines.
Differential pressure transmitters, as the detection and conversion part of process control systems, convert process parameters such as differential pressure (pressure), flow rate, and liquid level of liquids, gases, or steam into unified standard signals (such as 4-20mA current), which serve as input signals for display instruments, arithmetic units, and regulators to achieve continuous detection and automatic control of the production process.