Monthly Archives: March 2016

Monitoring the Transportation of Liquids

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities and you. In this blog we’ll be discussing the transportation of liquids.

Monitoring the Transportation of Liquids

The transportation of liquids can take many forms from pipelines to trucking to shipping and more. In many cases, monitoring the transportation process requires high pressure sensors with media isolation. Ceramic pressure sensors are a frequently used technology to satisfy both high pressure and media isolation requirements. The highly media compatible ceramic material can be exposed to many harsh chemicals. However, even water can pose a threat to normal sensors that are not intended for contact with materials beyond non-corrosive, non-ionic working fluids. The ceramic pressure sensor design can withstand maximum pressure range of up to 6000 PSI. For sensors such as, All Sensors’ newest CPM 602 series, the ratiometric sensors with total error better than 0.4% FS and ability to operate from supply voltage of 2 to 30 VDC in operating temperatures from -40 to 135°C further simplifies the monitoring process.

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What do you think/Comments?
Do you have a pressure sensing question? Let me know and I’ll address it in an upcoming blog.
-Han Mai, Senior Marketing Specialist, All Sensors Corporation (hmai@allsensors.com)

Media Isolated Pressure Sensors

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities and you. In this blog we’ll be discussing media isolated pressure sensors.

Media Isolated Pressure Sensors

Unlike many other sensor applications, pressure sensors frequently have to contact some pretty nasty chemicals. Sensor manufacturers usually qualify their sensors for restricted usage with statements such as “intended for use with non-corrosive, non-ionic working fluids such as air, dry gases, etc.” This means that the user who has an application that does not meet these criteria, either cannot use a product that meets all the other application requirements or has to take steps to protect the sensor and assume any risk regarding the protection methodology.

In contrast, sensors designed specifically for harsh environments open many new applications in areas including medical, environmental controls, plant and mechanical engineering as well as automotive. In many cases, the technology changes for these more rugged sensors from a silicon, microelectromechanical system (MEMS) material to a ceramic material but still retains a monolithic design. A flush membrane makes it easy to interface these types of pressure sensors to hydraulic fluids and even extends the pressure range up to 6000 PSI. With the CPM 602 series, All Sensors now participates in these more demanding applications.

CPM 602

A ceramic pressure sensor overcomes many of the limitations of silicon-based MEMS pressure sensors.

What do you think/Comments?
Do you have a pressure sensing question? Let me know and I’ll address it in an upcoming blog.
-Han Mai, Senior Marketing Specialist, All Sensors Corporation (hmai@allsensors.com)

Out of this World Pressures

Welcome to All Sensors “Put the Pressure on Us” blog. This blog brings out pressure sensor aspects in a variety of applications inspired by headlines, consumer and industry requirements, market research, government activities and you. In this blog we’ll be discussing pressure outside of our blue planet.

Out of this World Pressures

The earth’s average atmospheric pressure is 1 bar (101.3kPa, 29.92 mm Hg or 14.69 psi). Temperature and altitude are among the factors that cause variations. At a specific location, the air pressure can vary about 10%. Leave this planet, where we have the weight of a life-producing atmosphere of oxygen and nitrogen exerting pressure on us and the situation is quite different.

In outer space, the pressure is 1.322 × 10-11 Pa – essentially zero, since there is very little air and hardly any water.

Our nearest neighbor, the moon, has a surface pressure at night of 3 x 10-15 bar (or 3 x10-10 Pa). In contrast, Mars has a layer of gases surrounding it composed mostly of carbon dioxide. As a result, the atmospheric pressure on the Martian surface averages average  750 Pa (0.109 psi) or about 1/100 of the Earth’s. At any given location on Mars, the air pressure can vary by as much as 50%.

Earth’s pressure variations at a given location seem small compared to these other locations. Measuring earth’s pressure variations is also quite easy and commonly performed with a 100 kPa absolute pressure sensor.

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The size difference between Earth and Mars is minor compared to the atmospheric pressure difference. Image courtesy of NASA.

What do you think/Comments?
Do you have a pressure sensing question? Let me know and I’ll address it in an upcoming blog.
-Han Mai, Senior Marketing Specialist, All Sensors Corporation (hmai@allsensors.com)