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Analysis of common faults in AST pressure sensors during use. AST pressure sensors are key components in closed-loop systems, providing safety, control, and alarm functions for various industrial products. Today, we will focus on the common faults that can occur with AST pressure sensors: 1. The pressure increases, but the transmitter does not show an increase in output. In such cases, first check whether there is any leakage or blockage at the pressure interface. If that’s not the case, examine the wiring; if the wiring is correct, then check the power supply. If the power supply is functioning properly, verify whether the sensor outputs a signal at zero pressure, or apply slight pressure to see if there is any change in the output. If there is a change, it indicates that the sensor is not damaged; if there is no change, then the sensor is damaged. Other possible causes of this situation could be damaged instruments, or problems with other components of the entire system. 2. The output of the pressure-boosting transmitter remains unchanged; then its output suddenly changes, and the zero point of the pressure-reducing transmitter cannot be restored. The most likely cause of this phenomenon is the seal ring of the pressure sensor; we have encountered this issue several times with our customers. Generally, it is due to the specifications of the sealing ring (it being too soft or too thick). When the sensor is tightened, the sealing ring gets compressed and blocks the pressure inlet of the sensor, preventing the pressure medium from entering. However, when the pressure becomes very high, it suddenly forces the sealing ring aside; the pressure sensor then changes in response to this pressure. When the pressure drops again, the sealing ring returns to its original position and blocks the pressure inlet once more, preventing the remaining pressure from escaping. As a result, the sensor’s zero point cannot be adjusted back to its normal level. The best way to rule out this cause is to remove the sensor and directly check whether the zero position is normal; if it is, replace the seal ring and try again.