Although the BP-A pressure transmitter is widely used in industrial fields, diffused silicon HESMANN sensors still have 3 typical pain points in practical applications: obvious temperature drift, insufficient long-term stability, and relatively weak overload resistance. In this article, engineers from Xi'an Shenghongchuang combine measured data from models such as P-P964/P-P972 to provide an in-depth analysis of these technical shortcomings and help operators avoid purchasing misunderstandings (also applicable to models such as DG1300-BZ-A).

1. Temperature Drift Issue: A Common Shortcoming of Diffused Silicon Sensors

When the operating temperature changes, diffused silicon HESMANN pressure sensors (such as the P-P964/P-P972 series) show obvious deviation in their output signals. According to data from the Xi'an Shenghongchuang laboratory, when the ambient temperature rises from 20℃ to 80℃, the zero drift of some models can reach ±0.1%FS/℃, far exceeding the temperature drift index of ≤±0.05%FS/℃ for new-generation products such as AST20HA. This characteristic is particularly critical in scenarios with large temperature differences, such as turbo-generator units and locomotive braking systems.

Typical Manifestations of Temperature Drift

• Measured values are systematically higher during high-temperature periods in summer
• Instantaneous over-limit alarms occur during low-temperature startup in winter
• Day-night temperature differences lead to frequent calibration requirements (with model 064G-G6532 as a typical example)

By contrast, the domestic general-purpose pressure transmitter AST20HA diffused silicon negative pressure sensor adopts an improved temperature compensation algorithm, with temperature drift control within its 0～70℃ compensation range better than the industry average, making it particularly suitable for industrial environments with large temperature fluctuations, such as petrochemical and metallurgical applications.

2. Long-Term Stability Defect: Why Is Frequent Calibration Required?

The silicon sensing element of the HESMANN sensor produces a creep effect under continuous pressure. Our tracking test on model DG1300-BZ-A-0.4/CJ/AE/FZ/W shows that after 6 months of continuous operation, about 23% of the samples exhibited an annual stability deviation exceeding ±0.2%FS, while AST20HA, through optimized packaging technology, can control annual stability within ±0.1%FS.

Operation and Maintenance Problems Caused by Insufficient Stability

3. Overload Resistance Limitation: When Pressure Suddenly Impacts

In hydraulic system pressure shock tests, after a 2x full-scale overload, about 15% of BP-A transmitter samples showed reduced sensitivity. In contrast, newer models such as M5156-000005-016BG, through structurally reinforced design, can withstand instantaneous pressure of 300MPa (take the smaller value). This is particularly important for scenarios with pressure peaks, such as air compression and constant-pressure water supply.

Engineering Practices for Overload Protection

1. Install a pulse damper at the pump station outlet
2. Reserve a 30% margin when selecting the range (as recommended for P-P974 selection)
3. Give priority to products with overload pressure reaching 2x FS

4. Solutions: How to Avoid Sensor Usage Pain Points

In response to the inherent defects of diffused silicon HESMANN sensors, modern pressure transmitters have developed a number of improved technologies. Taking AST20HA as an example, it uses laser marking to ensure traceability, and through the combination of a diffused silicon sensor and 316 stainless steel material, it performs excellently in scenarios such as building automation and laboratory calibration.

Key Indicators for Purchasing Pressure Transmitters

• Temperature drift coefficient: Compare the ±%FS/℃ values within the -20～85℃ range
• Long-term stability: Require measured data in ±%FS/year
• Overload factor: For hydraulic systems, ≥2x range is recommended
• Media compatibility: Confirm whether 316 stainless steel is suitable

Summary and Recommendations

BP-A and similar diffused silicon HESMANN pressure transmitters have inherent limitations in temperature adaptability, long-term stability, and overload resistance. For strict application scenarios such as power station inspection and environmental monitoring, it is recommended to choose high-performance models with temperature drift ≤0.05%FS/℃ and annual stability within ±0.1%FS. As a professional pressure sensor manufacturer, Xi'an Shenghongchuang Instrumentation can provide complete technical parameter comparisons for models such as P-P962/P-P981 to help users make accurate selections.

Consult now:If you would like to learn how to select the most suitable pressure transmitter for your hydraulic control system or turbo-generator unit, please feel free to contact our engineering team for customized solutions.