How Baumer’s hygienic pressure sensor technology provides fast and high-precision pressure measurement

High precision and reliability are two key elements when it comes to choosing pressure sensor technology for any application. This is even more pertinent when you are working with hygienic process equipment since there is absolutely no margin for error due to the potentially grave consequences.

Leading pressure sensor technology manufacturers, Baumer, supply hygienic pressure sensors that support a variety of applications. This includes CIP systems where hydrostatic level measurement is required, as well as sterile air filters which rely on differential pressure measurement. In this article, we explore how Baumer’s hygienic pressure sensor technology provides fast and high precision pressure measurement.

How does a pressure sensor work?

Pressure sensor technology works by providing precise and reliable solutions for any task in pressure transmitters. How they deliver these solutions is customisable based on several important factors, which include:

• Installation Conditions (flush, non-flush)
• Application requirements (hygienic, industrial)
• Media Properties (liquid, gas).

There are four different pressure types: absolute, relative, compound, and differential. It is important to understand what each of these is.

Types of Pressure

• Absolute pressure relates to the measurement of pressure, with respect to vacuum. The pressure sensor technology used for this would have to be leak-proof and without relative compensation. An example of absolute pressure is steam pressure.
• Relative Pressure relates to pressure measurement, with respect to atmospheric pressure, and would use pressure sensor technology with relative compensation. Because this requires an ‘open’ sensor, it is influenced by its surroundings and therefore is used for the monitoring or control of physical processes with respect to ambient conditions. For example, a typical application would be hydrostatic pressure measurement in ventilated tanks.
• Compound Pressure which is relative to the measurement of gauge or differential pressure.
• Differential Pressure which relates to the measurement of the difference between two pressures.

In order for measurement of any of the above types of pressure to be successful, there are four factors to take into account:

1. Precision
2. Accuracy
3. Standard error measurement
4. Maximum error of measurement.

With these things in mind, we can now look at how pressure sensor technology works for hygienic applications.

How does a pressure sensor work for hygienic applications

To explain how Baumer’s pressure sensor technology benefits applications where hygiene standards are paramount, we look at the success they had working with leading sterile processing and infection control specialists, the Belimed Group.

The challenge that Belimed had revolved around the applications they provide within the pharmaceutical and biotech industry. The variety of hygienic process equipment that requires sterilisation in these industries is enormous. At the same time, the hygienic requirements for these products are highly stringent, with no room for compromise when it comes to quality compliance.

With strenuous conditions, including varying temperatures that range from 0–135°C and pressure fluctuations ranging from 50 – 3100 mbar, Belimed required pressure sensors that could deliver reproducible measuring accuracy on a consistent basis. Baumer’s PBMH sensors were able to provide the best components to assist, whilst meeting Belimed’s expectations.

Belimed’s BST, PST, and LST sterilisers are used worldwide and are developed to ensure compliance with the current cGMP, GAMP V, and FDA recommendations and directives. The use of Baumer’s hygienic pressure sensor technology was pivotal to them maintaining these accreditations. Three PBMH pressure sensors were used in the sterilisation chambers of Belimed’s new BST and PST series, with each one ensuring compulsory standard requirements were maintained.

One of the PBMH pressure sensors was positioned on the steam supply line. Its purpose is to monitor the steam delivery pressure, ensuring that it continuously exceeds both an absolute and relative value, compared to the chamber pressure. The other two are positioned on the sterilisation chamber itself. Their purpose is to ensure control during the pressure-related sterilisation process. The reason there are two of these is to ensure the process is recorded separately from the general process control, so they monitor each other to consolidate this.

For more information about Baumer’s hygienic pressure sensor technology visit www.baumer.com.