Determination of the measurement range of vacuum pressure switches

Determining the measurement range of a vacuum pressure switch requires a comprehensive consideration of multiple factors such as the normal operating range of the system, pressure fluctuation conditions, equipment safety margin, special requirements of application scenarios, and the balance between cost and performance. The following is an introduction for you:

Understand the normal working range of the system

Clarify the system pressure range: First, conduct a detailed analysis of the system that requires the use of a vacuum pressure switch to determine the vacuum pressure range of the system during normal operation. For example, in a vacuum adsorption system, through theoretical calculation and practical tests, it is known that when the system is working normally, the vacuum pressure usually fluctuates between -0.05MPa and -0.09MPa. Then, the measurement range of the vacuum pressure switch should cover this interval to ensure that the working status of the system can be accurately monitored.

Consider the pressure change trend: In addition to understanding the current normal working pressure range, it is also necessary to consider the possible pressure change trend of the system in the future. If the system may undergo upgrading and transformation, or if the production process changes, resulting in an expansion of the working pressure range, then when choosing the measurement range of the vacuum pressure switch, a certain margin should be reserved.

Evaluate the pressure fluctuation situation

Analyze the fluctuation range: The vacuum pressure in the system is often not constant and there will be certain fluctuations. It is necessary to analyze the magnitude of the pressure fluctuation. If the fluctuation is large, the measurement range of the vacuum pressure switch should be wide enough to avoid misoperation or damage of the switch due to the pressure exceeding the measurement range. For instance, in some chemical production processes, due to the instability of the reaction, vacuum pressure may fluctuate significantly within a short period of time. At such times, it is necessary to select a vacuum pressure switch with a wide measurement range.

Determine the fluctuation frequency: The frequency of pressure fluctuations also affects the selection of vacuum pressure switches. If the frequency of pressure fluctuations is high, it is necessary to select a switch with a faster response speed, and the measurement range should be able to adapt to such rapidly changing pressure. Otherwise, the switch may not be able to detect pressure changes in a timely and accurate manner, thereby affecting the normal operation of the system.

Consider the safety margin of the equipment

Set safety upper and lower limits: To ensure the safe operation of the equipment, a certain safety margin needs to be set when determining the measurement range of the vacuum pressure switch. Generally speaking, both the upper and lower limits of the measurement range should be slightly wider than the normal working pressure range of the system. For example, if the normal working pressure range of the system is -0.06MPa to -0.08MPa, then the measurement range of the vacuum pressure switch can be set to -0.05MPa to -0.09MPa. In this way, even if there is a brief abnormal fluctuation in the system pressure, the switch can still work normally and issue an alarm signal in time.

Dealing with emergencies: Safety margin can also help equipment cope with some unexpected situations, such as equipment failure, pipeline blockage, etc., which may cause a sharp increase or decrease in vacuum pressure. With sufficient safety margin, the vacuum pressure switch can act promptly in these extreme situations to protect the equipment from damage.

In combination with the special requirements of the application scenarios

High-precision measurement requirements: In some application scenarios with high demands for vacuum pressure measurement accuracy, such as semiconductor manufacturing and precision instrument inspection, vacuum pressure switches with a narrower measurement range but higher precision need to be selected. Because the narrower the measurement range is, the higher the resolution of the switch within the measurement range will be, and it can detect the minute changes in pressure more accurately. For instance, in the semiconductor manufacturing process, even the slightest change in vacuum degree may affect the quality of the product. Therefore, a vacuum pressure switch with a measurement range from -0.1MPa to 0MPa and an accuracy of ±0.1%FS is required.

Adaptability to harsh environments: If the application environment has harsh conditions such as high temperature, high humidity, strong vibration, and corrosive gases, it may affect the performance of the vacuum pressure switch. In this case, in addition to considering the measurement range, it is also necessary to select a switch with good environmental adaptability. For instance, in the production workshops of chemical enterprises, due to the presence of corrosive gases, vacuum pressure switches with high enclosure protection grades and corrosion resistance need to be selected. At the same time, their measurement range should be able to meet the pressure monitoring requirements of the production process.

Balance cost and performance

When choosing a vacuum pressure switch, cost is also an important consideration based on the budget. Generally speaking, the wider the measurement range, the higher the accuracy and the better the performance of a switch, the higher its price will be. Therefore, it is necessary to find a balance point between cost and performance based on the project's budget and actual requirements. If the requirement for measurement accuracy is not particularly high and the budget is limited, a switch with a moderate measurement range and relatively low price can be chosen. If high measurement accuracy and reliability are required and the budget is sufficient, then a switch with better performance can be selected.

Consider long-term usage costs: In addition to the initial cost of purchasing the switch, its long-term usage costs, such as maintenance costs and replacement costs, also need to be taken into account. Some vacuum pressure switches with reliable quality and stable performance, although they have a relatively high purchase price, have a low failure rate and relatively low maintenance costs during long-term use. Overall, they may be more cost-effective.