KELLER Pressure Japan List of Products and Services

In the field of pressure measurement technology, the type of pressure varies depending on the reference point (reference pressure). 【Absolute Pressure】 In absolute pressure, the process pressure is measured with a vacuum as the reference. In the manufacturing process, the back side (reference side) of the diaphragm within the sensor element is set to vacuum and sealed in that state. When atmospheric pressure is applied to the diaphragm, the sensor measures the atmospheric pressure (meteorological atmospheric pressure). All fundamental physical formulas related to pressure are based on absolute pressure data. 【Gauge Pressure】 In gauge pressure, the process pressure being measured is referenced against atmospheric pressure. In other words, it measures the difference between the process pressure and the current atmospheric pressure. Since atmospheric pressure is affected by altitude and weather, it constantly fluctuates. Therefore, for processes where variations from atmospheric pressure are significant, gauge pressure measurement is appropriate. The back of the measurement cell in gauge pressure sensors always has a vent hole, allowing the sensor element to reference atmospheric pressure within the housing. Gauge pressure is the most common type of pressure measured by pressure sensors and is used in nearly all applications and industries. For shielded gauge pressure and differential pressure, please refer to the related links below!

How do differential pressure sensors work, and how do they differ from other sensor types? Gauge pressure and absolute pressure sensors have defined reference points for measuring pressure differences (for absolute pressure: absolute vacuum, for gauge pressure: atmospheric pressure). In contrast, differential pressure sensors measure the difference between two pressures without defining a reference point. Differential pressure sensors can be made in various structures, but one feature of KELLER Pressure's products is that there is a type that can use liquid in both ports (e.g., model PD-33X). They can measure differential pressure with high resolution. There are also sensors that use two absolute pressure measurement cells to measure two pressures and determine the differential pressure through electronic circuits (model PD-39X). This structure is particularly suitable for high-pressure applications. Typical applications of differential pressure sensors: 1. Flow measurement There are several methods for measuring flow, but one common method is differential pressure measurement through an orifice plate. 2. Level measurement of liquefied gas tanks Liquefaction reduces volume, allowing for transportation and storage. Why is differential pressure measurement suitable for this water level measurement? For more details, please visit the URL below!

KELLER Pressure has been supplying pressure sensors to a wide range of sectors in the aerospace industry since 1997, and its pressure measurement technology has proven its reliability over hundreds of thousands of hours of flight. Reliability is paramount in the aerospace field, and the products used have demonstrated this aspect. 【Example of Achievements: Space Sector】 - Rockets (fuel, oxidizer) - Satellites (barometric measurement during atmospheric entry) - Combustion pressure measurement - Aircraft attitude control - Detonation - International Space Station (ISS) 【Example of Achievements: Aviation Sector】 - Pressure control in the cabin - Hydraulic distributors and filters - Valve control - Fuel pumps - Refueling systems - Air conditioning systems - Ventilation - Emergency oxygen supply for pilots You can see how different each application is and how broad the demands for pressure measurement technology are. While custom solutions are available, KELLER's strength lies in its extensive track record with standard catalog products. This significantly improves parts procurement and management, costs, and delivery times. Please consult with KELLER, which has strong expertise in the aerospace field!

Pressure peaks in closed systems can cause significant damage and are complex phenomena. But what exactly is a pressure peak? How does it occur, and how can we protect the system from pressure peaks? We will explain the role of precise measurements in ensuring the safety and efficiency of pressure systems. 1. What is a pressure peak and why does it occur? The physical principles behind the phenomenon are Newton's three laws of motion and Bernoulli's principle. What causes water hammer and cavitation, and what are their effects? 2. Preventive measures Using simulations, protective components such as pressure dampers, pressure reducers, and check valves, as well as pressure sensors. 3. Why are pressure sensors necessary to protect the system from pressure peaks? Continuous monitoring with sensors allows for real-time recording of pressure peaks and can trigger automatic responses such as valve opening and closing. In the event of a failure of system components or protective parts, it can not only be directly detected but also prevented. Alarms can be automatically sent to responsible personnel via email, IoT, cloud, etc., in case of anomalies. For more details, please refer to the related links below!

The Dutch public enterprise WMD Drinkwater is monitoring groundwater extraction using the KELLER DCX-22AA groundwater data logger. The evaluation points for the DCX-22AA by WMD Drinkwater are: 1. The best cost-performance ratio 2. The barometric correction system is very simple and convenient 3. All functions are overwhelmingly user-friendly, and linking the serial number with the installation location is easy. Barometric correction is performed by a second pressure sensor within the communication unit. The DCX-22AA is equipped with real-time barometric correction functionality, making it suitable for purposes such as groundwater level measurement and sewage overflow detection. The entire sensor is waterproof (IP67), so there is no problem even if the measuring tube gets flooded. Since the PC connection part of the communication unit is located at the top of the measuring tube, there is no need to remove the tube when reading data. This allows for real-time monitoring of measurement data and easy comparison with manually measured values. The barometric correction feature eliminates the need for additional air pressure loggers for installation and reading, as well as manual barometric correction, simplifying system operation. For more details, please refer to the related links below!

Keller's pressure sensors play a crucial role in hydrogen engine-equipped racing cars. This is because extremely high precision and reliability are essential in hydrogen systems within motorsports. Keller's pressure sensors are used in fuel cell powertrains, supporting the precise monitoring and control of hydrogen and air circuits under harsh high-performance conditions. 〇 Hydrogen Loop Keller's pressure sensors monitor the flow of hydrogen within the fuel cell by measuring optimal pressure levels, contributing to the realization of efficient electrochemical reactions. 〇 Air Loop Accurate pressure measurements are essential for the optimal management of oxygen supply, which directly impacts the efficiency and output of the fuel cell. 〇 High-Pressure Hydrogen Line Keller's pressure sensors are widely adopted in high-pressure hydrogen lines, as well as in hydrogen-driven test benches and onboard storage systems. In motorsports, reliability is paramount in a world where every second counts. Additionally, components that can withstand extreme pressures and rapid changes in load under harsh conditions are indispensable. Using Keller products, which boast the highest levels of precision and reliability and are Swiss-made, is a testament to a deep commitment to quality. For more details, please refer to the related links below!

Hydrogen is at the center of energy conversion, bringing unique possibilities for the decarbonization of industries and the transformation of energy consumption. Hydrogen is considered an environmentally friendly fuel because it does not release harmful exhaust gases such as CO₂, nitrogen oxides, or particulate matter when used for energy generation. However, hydrogen gas, which is regarded as one of the pillars of the future of energy, faces significant technical challenges in terms of storage, transportation, and measurement. How are KELLER's pressure sensors designed to meet these requirements? KELLER's hydrogen market specialist will answer that! (The article can be found through the related link below) 1. What is hydrogen? 2. Hydrogen as a fuel 3. Storage and transportation of hydrogen Comparison of hydrogen consumption and drum capacity, gaseous hydrogen, liquid hydrogen, and other methods 4. Challenges in pressure transmitters and hydrogen measurement Hydrogen embrittlement, permeation, leakage, ATEX certification, and intrinsic safety explosion protection 5. Introduction to pressure sensors for hydrogen KELLER's pressure sensors for hydrogen are products that meet stringent safety and performance standards, addressing various needs across the entire hydrogen supply chain, including refining, green ammonia production, metallurgy, storage, transportation, and electrolysis!

As attention focuses on hydrogen, which is considered a pillar of the future of energy, the importance of electrolyzers that decompose water into hydrogen is increasingly rising. In a proton exchange membrane (PEM) electrolyzer, water enters one side of the device, and hydrogen passes through a permeable membrane to the opposite side due to the electric current, resulting in the decomposition of water into oxygen and hydrogen. Since hydrogen is often stored at high pressure after electrolysis, it is considered preferable to operate the electrolyzer at high pressure as well, as this can eliminate the need for additional compression processes. Therefore, it is necessary to control the pressure of the oxygen and hydrogen generated in the electrolyzer, and even if this can be achieved through back pressure control, it is essential to minimize the pressure difference between the two flows to avoid mechanical stress on the electrolyzer's membrane. For example, what should be done if the pressure difference between the oxygen side and the hydrogen side in a high-pressure electrolyzer is low, ranging from 1 to 10 kPa (which is the maximum pressure difference that the membrane can handle)? What if a pressure measurement accuracy of <0.1% FS is required? This is where Keller's differential pressure sensor PD-39X comes into play. The PD-39X is equipped with two absolute pressure sensors, excels in pressure resistance on one side, and can achieve an accuracy of 0.1% FS. For more details, please refer to the related links below!

Using a pressure transmitter makes measuring pressure easy. However, how can we design and manufacture a perfect pressure transmitter? What is necessary to create an accurate and reliable measurement system? Our Technical Director, Bernhard Vetterli, explains. You can find the article through the related link below!

Keller's pressure sensors are used in rockets that fly to the thermosphere! SSC (Swedish Space Corporation) is a global leading company that provides cutting-edge space engineering, satellites, and launch services. SSC's rocket, the Suborbital Express, flies to an altitude of 260 km into the thermosphere, conducting scientific experiments in a microgravity environment on behalf of research institutions and companies. The experiments are conducted in a microgravity state, after which the rocket falls back to Earth. After a helicopter retrieves the rocket, SSC evaluates and analyzes the collected data and shares it with the users. In this rocket launch, Keller's pressure sensor PAA-33X was incorporated into the experimental module "ARLES-II." Prior to this, in the summer of 2019, Keller's pressure sensors were also used for pressure monitoring in the experimental module "ARLES-I." Using the pressure sensors, the pressure within a series of experimental cells was monitored, where experiments involving droplets and graphene particles (graphene is considered a future material due to its tear resistance, high elasticity, and conductivity) were conducted. Keller sensors were also used to measure the gas pressure inside the nitrogen tanks on board!

KELLER has been supplying pressure sensors to various aircraft sectors since 1997. - Pressure control in the cabin - Hydraulic distributors and filters - Valve control - Fuel pumps - Refueling systems - Air conditioning systems - Ventilation - Emergency oxygen supply to pilots Approximately 40,000 KELLER sensors are in operation in the sky, with about 30,000 used for cabin pressure control. Accurate control of cabin pressure contributes to comfort, especially during takeoff and landing. Currently, all Airbus models and Boeing's 787 (Dreamliner) utilize KELLER's pressure measurement technology. Their reliability has also been proven. For example, cabin pressure sensors require 200,000 to 400,000 hours of error-free operation, and one of our major customers confirmed over 1 million hours of MTBF during a year of observation. In addition to the detailed explanation above, you can also enjoy the following in the "Related Materials": 1. How safe is air travel now? 2. Where are the 10 types of KELLER pressure sensors used? 3. Delving into the secrets of the Airbus A380, Airbus A400M, and Boeing 787 (Dreamliner).

The basic principle of piezoresistive pressure measurement is the same as that of resistive pressure measurement, which captures changes in resistance. However, what are the advantages of using piezoresistive elements? This also explains not only the benefits of piezoresistive technology but also the aspects to be cautious about. Download materials from the related catalog!

The pressure sensors produced by KELLER in Switzerland are the original products invented over 50 years ago by founder Hannes W. Keller. Each package bears our quality seal, proving that all delivered products are within the specified accuracy class. KELLER symbolizes high-precision measurement technology. In 1966, Hannes W. Keller (commonly known as HWK) was working at the Honeywell Research Center in Minneapolis, USA. There, he invented the integrated silicon measuring cell, a high-precision measuring element manufactured using semiconductor technology, in collaboration with A.R. Gias. This silicon measuring cell was already incorporated into Honeywell's process transmitters and introduced to the American market in 1971. HWK brought this young invention back to Switzerland, developed the first high-precision static pressure transducer, and has been manufacturing it at the headquarters in Winterthur, Switzerland, since 1974. On July 25, 1978, HWK's invention was officially patented (U.S. Patent No. 4103273). The patent number is also embedded in the quality seal. For more details about KELLER quality, please refer to the related links below!

Main Features 1. Suitable for pressure measurement of viscous liquids such as ink 2. Suitable for applications where regular cleaning is desired 3. Can be used in food processes if it is a clamp type A typical pressure sensor has a screw at the tip and a diaphragm that receives pressure behind it. If the measurement target is air, there is usually no problem with the standard structure. However, there are inquiries such as "I want to measure the pressure of ink" and "I need a structure suitable for cleaning since I regularly clean the pressure receiving part." In such cases, the standard structure does not allow visibility into the interior, making it impossible to confirm whether it has been cleaned properly. In such situations, the pressure sensor with a "flush diaphragm" that has the pressure receiving surface protruding is effective. KELLER offers a wide range of products, including a minimum range of 30 kPa and an accuracy of 0.05% FS, and has a wealth of experience. If you are interested, please feel free to consult with us.

FPT Motorenforschung AG is headquartered in Albon, Switzerland, and develops engines for vehicles and machinery in the powertrain division of CNH Industrial. Approximately 220 staff members are on-site developing new FPT products for commercial vehicles, construction machinery, agricultural machinery, industrial applications, and marine use, with engines being tested on a total of 30 test benches. To measure engine efficiency, FPT Motorenforschung uses tools such as the M5 series pressure sensors from KELLER, a specialist in pressure sensors based in Switzerland. "The engines we develop and test in the factory meet the most stringent quality requirements in terms of materials, emissions, and efficiency. This means that when inspecting engines on the test bench, we must consider all variables that affect engine performance. Therefore, precise measuring instruments are required to obtain accurate and reliable measurements even under special conditions inside the engine," said the head of the Testing Engineering/Electronic Measurement Department at FPT Motorenforschung AG. For more information, please see the related links below.

Removing and capturing CO2 from the atmosphere in a practical and cost-effective manner is a daunting task, but we will introduce examples of manufacturers that are conducting research and development based on solar cell materials. They have successfully achieved CO2 capture at low power consumption and dramatically reduced CAPEX (capital expenditure) costs. This company has also significantly reduced energy consumption, realizing a cost-effective DAC technology. Why has Keller's high-precision pressure sensors come to be used in that process? We will reveal the secret!

You are likely familiar with the task of removing snow that has accumulated on a car or ice that has formed on the windows. The same task is necessary for aircraft when it starts to snow or ice forms. The process of removing ice or snow from an aircraft is known as de-icing. De-icing is performed in specially designated de-icing areas and is scheduled just before the aircraft takes off. This is because ice and snow not only increase the weight of the aircraft but can also impair its aerodynamic characteristics. De-icing is carried out using a liquid that contains at least 50% glycol mixed with water, and there are a total of four types of liquids that can be used for de-icing. At Amsterdam's Schiphol Airport, the mixture used for de-icing is stored in large heated tanks and is pumped into what is known as "Safeaeros" before being used on the aircraft. Safeaeros is a type of spray vehicle specially developed for this purpose. At Schiphol Airport, four Safeaeros vehicles are used per aircraft (two in front of the main wings and two behind the tail).

The unit of force, the newton, is named after the British physicist/mathematician Isaac Newton. However, he also invented something completely different. It is for cats... The correct answer is in the YouTube link below!

The deeper you go into the ocean, the greater the pressure becomes. At the deepest part of the ocean (about 11,000 meters), the pressure is an astonishing 1,100 times that of the sea surface! The deepest fish discovered was found at a depth of 8,300 meters (in the Izu-Ogasawara Trench). How can fish survive in such high-pressure deep-sea environments? One reason is believed to be that they possess a special substance called TMAO (trimethylamine N-oxide) that helps them cope with the pressure. TMAO plays a role in preventing proteins inside cells from being crushed by water pressure. However, there are things that TMAO cannot do. For that... check out the YouTube link below!

The industrial, energy, and mobility markets are undergoing significant transformation, but at the same time, they face many challenges. Keller will contribute to solving these issues with pressure sensors! Challenge 1: Permeation → Gold-plated diaphragm Challenge 2: Hydrogen embrittlement → Special stainless steel with increased nickel content Challenge 3: Gas leakage → Metal seal connections Challenge 4: Intrinsic safety explosion protection → Obtaining ATEX and IECEx certification

Hydrogen poses a risk of permeation leading to leaks due to being the smallest molecule on Earth. It also has a highly flammable characteristic when exposed to air. Therefore, it is crucial to prevent leaks from hydrogen tanks or to detect them early. Keller's pressure sensors are used for leak testing in hydrogen fuel cells. The hydrogen fuel cell has three channels: one for air (oxygen), one for hydrogen, and one for cooling. Nitrogen is used first, followed by hydrogen, to detect leaks within the system. The pressure values at the inlet and outlet of the fuel cell are continuously recorded and displayed on the screen in real-time, allowing for ongoing monitoring. A drop in pressure indicates a leak in one of the three flow paths. Keller's pressure sensors have high accuracy, enabling them to detect leaks in even the smallest areas that are not sealed, ensuring the safe use of fuel cells. For more details, please refer to the related materials below.