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Countermeasures for incorrect pressure indication on Yokogawa transmitters: 1. Is the temperature of the pipeline too high? The operating temperature range for the pressure sensor in Yokogawa transmitters is -25~85°C, but it is advisable to keep the temperature within -20~70°C during actual use. Solution: Add a buffer tube to aid heat dissipation; it is advisable to fill the buffer tube with cold water before use, in order to prevent overheated steam from directly hitting the sensor and thus damaging it or reducing its lifespan. 2. Is the enclosure of the Yokogawa transmitter properly grounded? Solution: Ensure that the equipment enclosure is grounded. 3. Is the wiring separated from that of the AC power supply and other power sources? Solution: Wire it separately from the AC power supply and other power sources. 4. Is the power supply of the Yokogawa transmitter functioning properly? Solution: If the voltage is below 12VDC, check for any heavy loads in the circuit; the input impedance of the transmitter’s load should satisfy RL≤(Voltage supplied to the transmitter – 12V)/(0.02A) Ω. 5. Is the reference pressure value accurate? Solution: If the accuracy of the reference pressure gauge is low, use a gauge with higher accuracy. 6. Is the range of the pressure indicating instrument consistent with that of the Yokogawa pressure transmitter? Solution: The range of the pressure indicating instrument must be identical to that of the Yokogawa pressure transmitter. 7. Are the inputs of the pressure indicating instrument connected correctly? Solution: If the input for the pressure indicating instrument is 4–20mA, then the output signal from the Yokogawa transmitter can be connected directly ； If the input to the pressure indicating instrument is 1–5V, a resistor with a precision of at least one part in a thousand and a resistance value of 250Ω must be connected in parallel at the input of the pressure indicating instrument, before connecting it to the input of the Yokogawa transmitter. 8. The input impedance of the load connected to the Yokogawa transmitter should satisfy RL ≤ (Voltage supplied to the Yokogawa transmitter – 12V) / (0.02A) Ω. Solution: If this condition is not met, appropriate measures can be taken depending on the situation; for example, increasing the supply voltage (but it must remain below 36VDC) or reducing the load. 9. Is the input terminal open circuit when the multi-point paper recorder is not recording? ； Solution: If there is an open circuit, then: a. No other loads can be connected ； b. Use another recorder for which the input impedance is ≤250Ω when no record is available. 10. Is the pressure sensor of the Yokogawa transmitter damaged? Severe overloading can sometimes damage the diaphragm. Solution: It needs to be sent back to the manufacturer for repair. 11. Are there any sands, impurities, etc. inside the pipeline that could block it? The presence of such impurities can affect the accuracy of measurements ； Solution: Impurities need to be removed, and a filter screen should be installed before the pressure interface.