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The sensitive components of the pressure transmitter’s measurement section are constructed using a fully welded design, while the electronic circuitry is assembled through wave soldering and connector installation. The overall structure is robust and durable, resulting in few failures. For the vast majority of users, if a malfunction is detected in a sensitive component, it is generally not possible to repair it oneself; instead, they should contact the manufacturer to have the entire component replaced. I. Inspection of the measuring section of the pressure transmitter. Faults in the measuring section of a pressure transmitter can cause it to have no output or to produce an abnormal output; therefore, the sensitive components used for measurement in the pressure transmitter should be checked first. 1. Remove the flange and check whether the diaphragm of the sensitive component is deformed, damaged, or leaking oil. 2. Remove the compensation plate without taking out the sensitive components, and check the insulation resistance between the pins and the housing; at a voltage not exceeding 100V, this insulation resistance should be no less than 100M. 3. Connect the electrical and gas circuits; when the pressure signal reaches the upper limit of the range, shut off the gas supply, and the output voltage and reading value should remain stable. If the output voltage drops, it indicates that there is a leak in the pressure transmitter, and the location of the leak can be identified using soapy water. II. Inspection of the pressure transmitter’s circuit section 1. Turn on the power supply, and after applying a specified input pressure signal, check the status of the voltage signal at the output terminal of the pressure transmitter. If there is no output voltage, check first whether the power supply voltage is normal ； Does it meet the power supply requirements? ； Are there any wiring errors between the power supply, the pressure transmitter, and the load equipment? A lack of voltage at the terminals of the pressure transmitter, or an incorrect polarity, can both result in no voltage signal being output by the pressure transmitter. If the above reasons are ruled out, further inspection should be carried out to check for any damage to the components in the amplifier board’s circuitry ； To check for poor contact in the circuit board connectors, one can compare the measured voltage with a normal instrument to that of the faulty instrument, thereby identifying the fault point; if necessary, the faulty amplifier board can be replaced. When inspecting flow-type pressure transmitters, special attention should be paid to taking anti-static measures for the J-type amplifier board. 2. After powering on and applying a given input pressure signal, if the output of the pressure transmitter is too high (greater than 10VDC) or too low (less than 2.0VDC), and there is no change in the output even after altering the input pressure signal as well as adjusting the zero and range screws. For such faults, in addition to checking for any abnormalities in the sensitive components of the pressure transmitter’s measurement section, it is also necessary to verify whether the \"oscillation control circuit\" on the pressure transmitter’s amplifier board is functioning properly. The normal peak voltage between high-frequency transformers T1-12 should be 25~35 VP-P ； The frequency is approximately 32kHz. Next, check the operating condition of each operational amplifier on the amplifier board ； Check for any damage to the components in each part. Such faults require the replacement of the amplifier board. 3. Pressure transmitters have very strict requirements regarding circuit design and manufacturing quality. In actual use, in the event of circuit failures, it is advisable to contact the manufacturer to have the faulty circuit board replaced, once such failures have been confirmed, in order to ensure the stable and reliable operation of the instrument over the long term. III. On-site fault inspection: The faults that occur at construction sites are, in the vast majority of cases, caused by improper use and installation methods, which can be summarized into several aspects. 1. The primary components (orifice plates, remote sensing connectors, etc.) are clogged or installed incorrectly, and the pressure sampling points are not appropriate. 2. Leakage or blockage in the pressure lead pipe, residual gas in the filling pipe or residual liquid in the filling tube, and deposits in the process flange of the pressure transmitter create a measurement dead zone. 3. The pressure transmitter is wired incorrectly, the power voltage is too high or too low, or there is poor contact at the connection between the indicator gauge and the instrument’s terminals. 4. It was not installed in strict accordance with the technical requirements; the installation method of the pressure transmitter and the on-site environment did not meet the technical specifications. All the faults mentioned above can cause abnormal output or inaccurate measurements from the pressure transmitter. However, through careful inspection, proper use and installation in accordance with technical specifications, and timely implementation of effective measures, these problems can be resolved. For those faults that cannot be fixed, the pressure transmitter should be sent to a laboratory or the manufacturer for further examination. For more information, please visit the company’s official website at http://www.yb1518.com/. Please retain this link when reproducing the content!