Teledyne Hastings Instruments Blog

This blog is the next installment in a series of blogs focusing on industrial gases. The first blog featured SF₆ and can be found here:   https://info.teledyne-hi.com/blog/sulfur-hexafluoride-gas-sf6 In this blog, we will explore one of the most useful, and well-known, of the industrial gases, carbon dioxide (CO₂).

CO₂ is an odorless and colorless gas. As a matter of fact, you exhale about a quarter liter of CO₂ every minute (https://www.nytimes.com/1990/08/14/science/q-a-burden-of-breathing.html). And while we are on the subject of breathing, it is interesting to note that it is usually the buildup of CO₂ that triggers a breath, not the lack of oxygen. A recent special feature in Gasworld US Edition noted that “low concentrations are not harmful, higher concentrations can affect respiratory function, cause excitation and depression of the central nervous system.”

The structure of CO₂ is linear. The electronic structure of the molecule features bonding pairs of electrons around the central carbon atom. These electron pairs repel equally while bonding to oxygen atoms. The equal repulsion is what gives CO₂ its linear arrangement. A diagram of the molecule is shown on right.

There are many fascinating uses of CO₂, some are well-known while others may be new to the reader.

• Used in industry to produce chemicals and as feedstock
• Used in the metals industry to improve the hardness of castings
• Often used as a carrier for spraying of paints or for spraying vegetable oils in cooking
• Liquid CO₂ can be used as a solvent in eco-friendly dry cleaning
• Solid CO₂ can be used for cold storage
• Jets of CO₂ are used for special effects in movies, live shows, and amusement parks
• Gas phase CO₂ is used for fire extinguishers
• Carbonated beverages

A quick note on purity... CO₂ used for fire extinguishers can be ~ 95% pure. However, the purity of CO₂ in carbonated beverages can be as high as 99.9995%.

A word on explosive decompression of elastomers when using CO_2. CO₂ is known to more easily penetrate elastomeric seals such as o-rings and diaphragms at pressures significantly higher than atmosphere which in turn can cause the host material to swell. If the pressure is suddenly decreased (i.e rapid decompression), the internal gas can rupture the elastomer and the seal can be compromised. There are a few things the user can try to reduce risk. First, select materials that are less susceptible. Viton® is often not a good choice for CO₂ applications. Second, if the application will allow, try to reduce the amount of time the elastomeric seal is held at elevated pressure. And third, when the pressure is reduced, allow more time for the CO₂ to exit the material.

Flow controllers from Teledyne Hastings are used to measure and control CO₂ flow in many of the aforementioned applications. The 300 Vue can provide all-metal seals and Kalrez® valve seat. (see diagram below). For users of the elastomeric-sealed 200 Series, we recommend Buna-N seals which are less susceptible to explosive decompression.

Teledyne vacuum gauges can be used with CO₂. The HVG-2020B (Click Here) is an excellent choice for measuring CO₂ from below 1 mTorr up to atmosphere. Convection driven pirani vacuum gauges, when used with gases other than N₂/air can have curious behavior as can be seen in the cartoon below.

The HVG-2020B vacuum gauge uses a gas-independent piezoresitive sensor that does not rely on convection affects and provides a more liner response to CO₂ across the entire measurement range.

If you would like more information about either the 300 Vue mass flow meters or controllers, or any of our vacuum gauges including the HVG-2020B, you can talk to any of our application engineers at 757-723-6531, or email hastings_instruments@teledyne.com or LiveChat with us at www.teledyne-hi.com

Special thanks to Lawrence Ferbee from the stockroom for his cartooning skills. If you would like to see Lawrence in action as he draws these, check out our HVG-2020B video:

https://www.youtube.com/watch?v=_Bk3Q7SpSUc

Viton® is a registered trademark of DuPont Performance Elastomers

Kalrez® is a registered trademark of DuPont Dow Elastomers

The use of Liquefied N₂ (LN₂) has revolutionized aluminum extrusion mold performance. CVS Corporation based in Gimpo, South Korea has developed a proprietary LN₂ cooling process that allows production output to more than double for some extrusion profiles. Production times vary based on the geometry of the extrusion profile. Ram speed test data can be found in Figure 1 below.

Figure 1: Extrusion Profile Table

The Aluminum Extrusion Mold Liquid Nitrogen Cooling System from CVS is designed to control the temperature of both the profile and the mold during the extrusion process. As the billet passes through the extrusion mold, the friction between the billet and the mold creates excess heat. This excess heat limits the extrusion ram speed and is the main cause of reduced productivity in the extrusion process. The CVS process maintains optimum profile and mold temperatures by using automated cryogenic proportional control valves to provide precision dosage of Liquefied N₂.

Figure 2: Aluminum Extrusion Mold Liquid Nitrogen Cooling System from CVS

Mr. Ko Hwa-Jin is the President of CVS Corporation and can be reached by email or website: www.ln2doser.com

Mr. Yoonk Min is the President of Inforad Corp. which is the distributor for Teledyne Hastings Instruments for South Korea. Mr. Min can be reached by email or website: www.inforad.co.kr

Wayne Lewey is the International Sales Manager at Teledyne Hastings Instruments and can be reached by email. 

Did you know? Even if your flow controller does not have the color touchscreen display, the 300 Vue flow line still allows you to switch between analog & digital control by using the zero button. (See the diagram below). You can also toggle between RS232 & RS485. This is a convenient feature when users want to switch their setup. Instructions can be found in the manual (pg. 14).

And, of course, we have our free Windows™ software. With the software, you can quickly configure and control your 300 Vue. And you can also record flow data and store to a file If you would like us to send a secure transfer download link for the free software, click here: https://www.teledyne-hi.com/resource-center/software

Using thermal mass flow instruments by Teledyne Hastings is an easy way to quickly and accurately measure gas flow. And in some cases, a mass flow instrument may be calibrated for one gas, but then the user may want to use the instrument in another gas. In this blog, we will show how to use GCFs (Gas Conversion Factors) when using flow instruments in different gases.

Before we get into GCFs, let’s quickly review the operation of one of our flow sensors. Below, we show a diagram of the 200 Series flow sensor. In this sensor, gas flows through a capillary tube which is heated in the middle to a temperature which is approximately 130°C. Two thermocouples, one upstream (TC-1) and one downstream (TC-2), measure the temperature. The temperature difference between the two thermocouples is proportional to the heat flow through the capillary tube. The heat flow, in turn, is proportional to the mass flow times the specific heat Cp of the gas. So, to first order, if we want to use a thermal mass flow meter that has been set up for one gas, and use it with another gas, we will multiply the output of the meter by the ratio of the specific heats. GCF ~ Cp1 / Cp2

There are a couple of things we need to point out. First, the ratio shown above is a simple approximation and does not tell the whole story. Next, the best GCFs are those that have been measured experimentally. However, in the case of dangerous gases, we use the best thermodynamic data available.

Here is a table of some common GCFs.

Next, we will discuss how we apply GCFs in practice. Let’s take an example of a flow meter that is calibrated for nitrogen. If we wanted to use the flowmeter in argon, we would take the output and multiply by the GCF for Argon.

Here is another example; suppose we have a meter that is calibrated in helium and we want to use it in hydrogen. You would start by dividing the output by the GCF for helium (think of it as converting to the nitrogen equivalent), and then multiplying by the GCF for hydrogen.

Remember, always use the appropriate set of GCFs for the flow series that you are using. In other words, if you are using our Digital 300 Series, don’t apply GCFs from a 200 Series manual – they are not the same. And certainly don’t use non-Teledyne table of GCFs for use with Teledyne flow products. They might get you in the ballpark, but they will not be your best conversion.

One other quick note about applying GCFs. Our line of flow power supplies, the THCD-101 (single channel) and the THCD-401 (four channel), can be used to quickly scale the analog input which is equivalent to applying a conversion factor. Let’s take another look at the Argon example. If we used the THCD-101 power supply with the nitrogen flow meter as shown below, at the nominal full scale of the flow meter, we will have a 5 VDC signal. If we want to use this same meter and power supply with Argon, we just need to “tell” the THCD-101 what value to display when it receives 5 VDC. So, if our flow meter was calibrated for nitrogen to give 5 VDC at 250 sccm, then the same flow meter will give 5 VDC in argon at 350 sccm. (250 * 1.4 = 350). So, we would then range the THCD-101 for 350 sccm. This can be done from the front panel or via the internal webserver.   

Now let’s make things a little more interesting and discuss a flow controller example. Analog flow controllers work by receiving a command signal (usually 0-5 VDC, or 4-20 mA) and then they adjust their control valve such that the flow, and thus the analog signal output, matches the command signal input. (You can think of it like the cruise control in your car – you tell it you want to go 78 miles per hour, and then the engine does what it needs to do to maintain that speed). In the case of a 0-5 VDC flow controller, a 5-volt setpoint command is instructing the flow controller to set the flow to 100% of full scale. The relationship between flow rate and command signal is linear, so if the user wanted to control at 25% of full scale, then they would send a 1.25 VDC command signal (0.25 * 5 VDC = 1.25 VDC).

Now, suppose we had an HFC-202 flow controller (200 Series) that was calibrated for 200 sccm of methane and we wanted to use it to control the flow of argon. What voltage level would we need on the command signal to have a flow rate of 100 sccm of argon? Let’s first determine the full-scale flow rate (5 VDC) when using argon:

Flow (Ar) = Flow (CH4)/GCF (CH4) * GCF (Ar) = (200 sccm / 0.77) * 1.401 = 363.9

So, a 5 VDC command signal will give us 363.9 sccm of argon. If we want 100 sccm, we would send:

Command Voltage = 100 sccm (5 VDC / 363.9 sccm) = 1.374 VDC.

Now, one important note about using flow controllers in different gases. Just because we can apply GCFs does not mean that a flow controller’s valve will work properly when switching from one gas to another. As an extreme example, a flow controller valve that has an orifice sized to handle hydrogen will have a hard time handling significant flows of large polyatomic molecules like C2H6.

Teledyne flow products are easy to install and use. And our application engineers are standing by to help. We can be reached by email (hastings_instruments@teledyne.com), by phone 757-723-6531, or via LiveChat on our website www.teledyne-hi.com or by clicking the contact us button below.

Over the next several blogs, we will be discussing various industrial gases. While some of these (carbon dioxide, argon, methane, and hydrogen) may be very familiar to our readers, other gases may not be as well known. In this blog, we will take a look at sulfur hexafluoride (SF₆), a gas that is one of the most important today in the utility industry.

SF₆ is an interesting gas primarily because of its electrical properties. Certain neutral gas molecules can easily capture free electrons and form stable negative ions. The efficiency of negative ion formation in a gas is determined by its electron affinity. SF₆ , it turns out, has a very high electron affinity and therefore has excellent electrical insulating strength. So, in an electrical discharge inside a volume containing SF₆ gas, the free electrons generated by the discharge are captured by neutral SF₆ to form negative ions. These large negative ions are not able to travel quickly and so the discharge is usually quickly extinguished. One other note about SF₆, the insulating property of the gas improves with increasing pressure. SF₆ is colorless, odorless, non-toxic, and non-flammable. As you can see, these properties make it very useful to the generation, transmission, and distribution of electricity. 80% of the world’s SF₆ gas is used by electrical utilities in circuit breakers, transformers, and gas insulted switches.

SF₆ is arranged in a hexagonal structure. Each of the six fluorine atoms shares two its electrons with the outer shell of the sulfur atom in the middle. This structure gives SF₆ its stability over a broad range of temperatures; the gas is thermally stable up to 500°C.

SF₆ is often used in high voltage breakers. One example is the so-called dead tank breaker. In a dead tank breaker, the tank is electrically tied to earth/ground. In the live tank version, the tank is floating at a higher voltage.

The “make/break” mechanism of the breaker is shown in the diagram below. As noted above, the insulating properties of SF₆ are improved with increasing pressure. So one of the jobs of the breaker’s piston actuation is to compress the SF₆ gas and force it to flow into the arc region. As the contacts are moved apart, current will try to continue to flow as an arc. Any resulting arc is quickly extinguished by the pressurized SF₆ flowing into the region. Incidentally, during breaker manufacturing, vacuum gauges from Teledyne Hastings are used to measure vacuum levels inside the vessel during pump down as the air is removed. After evacuation, the region can be filled with SF₆.  

OK, one last note about SF₆ to conclude this blog and this falls under the category of “Don’t Try This at Home.” Just like Helium will make your voice sound higher if inhaled, SF₆ will make your voice sound lower. You can find many demonstrations of this on YouTube. The most famous example is probably the demonstration on “The Big Bang Theory.” However, SF₆ is one of the most powerful greenhouse gases and its release into the atmosphere should be minimized.

Teledyne Hastings builds both vacuum and flow instrumentation which can easily work with SF₆. Note that SF₆ has a very high thermal conductivity. Conceptually, this makes sense because the gas molecule has many degrees of freedom – translational, rotational, and vibrational.  The GCF (gas conversion factor) for SF₆ use with the 300 Vue line of flow controllers is 0.27. In other words, if you wanted to use a 300 Vue mass flow meter that had been set up for nitrogen, you would need to multiply the output by the 0.27 GCF. The good news for you is that with the 300 Vue, you can just select the gas from the front panel as shown in the photo below. Just keep in mind that if you wanted to do this, the required pressures for the valve are going to be different. You will likely need a higher pressure drop. But as always, our application engineers can be reached by email, phone, or Live Chat on our website: www.teledyne-hi.com

Several months ago, I saw an interesting article about a cool museum called the Neon Museum which is located in Las Vegas.

https://www.neonmuseum.org/

According to the museum’s website, “the Neon Museum is a non-profit 501 (c) 3 organization dedicated to collecting, preserving, studying and exhibiting iconic Las Vegas signs for educational, historic, arts and cultural enrichment.” The museum holds over 250 neon signs. Tours are given both day and, of course, at night. The main collection in the “Bone Yard” includes signage from Caesar’s Palace, The Stardust Resort and Casino, and the recently added giant guitar from the now closed Hard Rock Café.

Some of the pieces are still operational and “live” shows are given nightly. Other signs are dormant and are lit up by flood lights.

(Photos Courtesy of the Neon Museum, Las Vegas, NV)

Production of neon light tubes requires vacuum pumps and, of course, reliable vacuum measurement. Typically, glass tubes are bent into shape and then pumped to around 1 Torr and energized using a glow discharge to clean up the tube. Next, the tube is evacuated to the mTorr region. Different gases are then backfilled to a few Torr which, when excited in a glow discharge, create various colors. Neon gives the classic neon red/orange glow while carbon dioxide produces white, helium gives yellow, and mercury can be blended with neon to produce blues. In some cases, coatings on the internal surface of the glass can be used to create additional colors. When using coatings, mercury is included in the gas to ensure that UV photons are created to activate the fluorescent coating.

A nice tutorial of glow discharge characteristics with some history is given starting on page 14 in the February 2020 issue of Vacuum Technology & Coating magazine.  https://digital.vtcmag.com/12727/26337/index.html

The new HVG-2020B from Teledyne Hastings is a great vacuum gauge for this application. The gauge uses two vacuum sensors: a piezoresistive sensor to measure pressures from atmosphere to 10 Torr and a thermal Pirani sensor to measure from 1 Torr to 0.1 mTorr. In between 1 and 10 Torr, the gauge uses a weighted average to ensure a smooth transition between the two sensors. The piezoresistive sensor is gas species independent, so no matter what gas is being backfilled, the piezoresistive sensor gives an accurate measurement. The Pirani sensor’s response is affected by the gas species, but the user can select a gas and the correction is made.

So, the next time you see a neon light, you can think about the vacuum gauge that was probably used to manufacture the gas tube. And if you’re ever in Vegas, check out the Neon Museum!

For more information about any of our vacuum gauges or our complete line of mass flow meters and controllers, we are here to help. You can contact us at hastings_instruments@teledyne.com , Live Chat on our website www.teledyne-hi.com , or call 757-723-6531 (800-950-2468). And to learn more about the HVG-2020B Vacuum Gauge, click the link below, “5 Reasons you need the HVG-2020B Vacuum Gauge.”

Teledyne Hastings is proud to announce our newest 4-channel power supply, controller and display, the THCD-401. The THCD-401 provides both ±15 VDC or 24 VDC to power our mass flow controllers, flow meters, vacuum gauges and pressure transducers. Feedback from connected devices is displayed on the bright, front panel LED display in 6-digit resolution, making open and closed channels easily identified at a glance. The THCD-401 can set a relay point for control of other processes and has a high accuracy of ± (0.02% of Reading + 0.01% of Full Scale). Custom configuring our products to customer needs is our specialty. Your THCD-401 can be factory configured to match the gas, range, units and the output of your instruments for out-of-box functionality.

What’s Improved?

In short, the THCD-401 was designed for exceptional user access and control.  The addition of a circular touch pad simplifies navigation through the unit’s various menu options, while left and right arrow keys allow easy selection of digits to be changed. Calibration is no longer needed for various levels of input voltage and built-in fuses provide additional surge protection.  Back panel communication ports have been streamlined and a USB-C and Ethernet port for serial communication have been added. 

The addition of Ethernet communication provides access to the newest feature that the THCD-401 has to offer; the internal web server! The web server can be accessed by entering the IP address of the THCD-401 into a browser’s address bar (requires static IP address configuration on the network prior to use). While the web server feature works best in Mozilla™ Firefox^®, it can be accessed via any browser you choose.  Figure 2 shows the web server interface with applications along the top navigation bar and a live data stream for remote read.

The web server allows you to name channels and adjust the range or units based on your device and the full scale (V) voltage output that it sends. This enables users to see the flow rate of a flow controller or meter, as well as the ability to OPEN/CLOSE all channels at the click of a button. Other applications include linearization, setting of a relay point and finding the total amount of gas that has passed through the device using the totalizer function.

It should be noted that while all these advanced features are available via the web server (Ethernet) connection, the THCD-401 also offers direct access to each via the front panel display menus using the circular touch pad.  This allows for quick and convenient setup of the channel’s full scale and range(V) for new devices.

If a relay point has been tripped, it will be indicated to the left of the channel’s name on the THCD-401 display. The display will also show the current mode of the set point, if it is not configured in AUTO mode. In OPEN mode, the set point outputs a voltage greater than the full scale of the device. In CLOSED mode the set point outputs a voltage less than the minimum output voltage of most devices. AUTO mode is dependent on the user defined set point configured through the THCD-401 physical buttons, digital communication or external input. 

More Information:

The THCD-401 was designed to be a highly flexible and multi-featured process display controller that can be panel mounted and capable of interfacing to an assortment of meters, controllers and gauges.  A powerful upgrade from the previous THCD-400 model, the THCD-401 adds digital communications, a bright LED display and a variety of customizable options to an already time-tested platform. To learn more about the
THCD-401 or any of our other vacuum and flow products, contact us at hastings_instruments@teledyne.com, call 1-800-950-2468, or click the button below.

The early part of the 1950’s was prosperous for Hastings due in part to the demand for the Raydist and large military contracts as a result of the Korean War. Sales nearly tripled between 1950 and 1953 and there were almost 200 employees.  Hastings had outgrown its space yet again and expanded to a 14,000 square foot building on Newcomb Avenue (current day location for Teledyne Hastings).  The building was originally used as a car barn for street cars, then as a World War I armory and eventually as a manufacturing plant for ladies clothing.

With the new location, other changes were happening as well.  Hastings entered into a joint venture to supply Raydist services for the petroleum industry in the Gulf of Mexico thus creating Offshore Raydist, Incorporated. Another company was formed out of Hastings at this time, Raydist Navigation Corporation (RNC).  RNC was set up to handle the leasing of Raydist equipment outside of the Petroleum industry.

During this period, most of the focus was on Raydist and trying to establish itself in new fields.  One area was to have the Raydist on the S.S. United States.  This superliner promised to be the fastest passenger liner in the world and would serve as a troop transport in the event of war.  Because of personal relationships, Hastings could test and prove that Raydist was the superior system of conducting the tests at a measured-mile course.  The test would use a specially-designed buoy which could be cast overboard and allowed to float freely during the trials.  The relay equipment would be installed in the buoy, while the S.S. United states would carry the master station.  Raydist would then record the liner’s speed as it steamed directly toward or way from the buoy.  The tests proved to be successful and resulted in the Raydist being approved for use on the S.S. United States.  This success lead to many other shipyard opportunities for Hastings.  Within a few years, Raydist dominated the sea trial business in the United States.

Raydist was also gaining momentum in the Hydrography and oil prospecting industry due to positive publicity from the Norfolk Corps of Engineers.  This publicity resulted in the first foreign Raydist sale in early 1951 to be used in charting the waters off Mozambique in southeast Africa.

During this time, Hastings completed a Raydist system for the All-Weather Flying Division of the Air Force.  It was to be used at Wright-Patterson Air Force Base in Dayton Ohio to test the accuracy of radar and other blind landing systems. Later that year, an automatic plotting board was developed to supplement the Raydist system.  The demonstration of this new product was a big event.  The board plotted a plane’s path as it performed skywriting maneuvers spelling HICO across the sky.

A small percentage of Hastings business during the early 1950’s was for instrument sales.  The most important of these products were the air-meters, vacuum gauges, flow meters, accelerometers and an electronic standard cell. In order to grow this part of the business, Hastings decided to set up a manufacturer’s representative program.  By the end of 1953, Hasting’s was looking forward to seeing this manufacturer’s representative program vastly increasing instrument sales.

(Image on right is the first Manufacturer Representative's car outfitted with Hastings products.)

For more information on Teledyne Hastings be sure to visit our website www.teledyne-hi.com or contact us

Information for this blog was derived from “The Story of Hastings-Raydist” book by Carol Hastings Sanders 1979

By 1947, the Hastings Instrument Company could count many successful projects.  Their list of products included the following:

• Raydist Navigation System
• Magnetic Switch and Coil
• Maximum Recording Accelerometer
• Visibility Meter

While the list of projects was impressive, the company wanted to grow their profits further. Charles Hastings decided to look at his business model and make some changes.  The company needed to raise capital for further development in order to become a sizeable company. Growth would give the company the ability to attract and close larger contracts.  To do this, Hastings decided to incorporate the business and offer 3500 shares of stock.  The company charter was received from the Commonwealth of Virginia on Valentine’s Day 1947. 

After several sales pitches and demonstrations, Hastings received two large contracts for Raydist. Along with these two contracts, the company was busy building Air-Meters for commercial sales.  Before selling the Air-Meters, the instruments needed to be calibrated.  In those early days, calibration was done by driving down the road holding a probe out the window while someone in the passenger seat held the Air-Meter.  When the car reached 5, 10, 15 etc… mph the passenger would make a note on the blank dial face and then return to the house where they would neatly letter the dial face.

During this period of growth, Hastings realized that it was time to find a new location for the business.  By now, there were 17 people working elbow-to-elbow at the Hastings’ home and that could not continue.  The company settled on temporary location in an old brick distributorship building that had a leaky roof and flooded at spring tides, but it was at the price they could afford.

By the spring of 1948, several Raydist contracts were in the works. Air-Meters continued to sell very well, and several instruments were about to be introduced.  That same year, the Hastings Company also moved into a more permanent building for its now 75 employees, which would grow to 118 by 1950.  To secure the company and continue to make profits, Hastings realized he needed to produce a Raydist for commercial use.  The company achieved this goal in 1950 with a sale to the Norfolk Corps of Engineers for hydrographic surveys and channel dredging.

By 1950, the line of Hastings Instruments increased to the following:

• Air-Meter
• Precision Air-Meter (for higher ranges and more accurate readings)
• Maximum Indicating Accelerometer
• Voltage-regulated Power Supply
• Electronic Standard Cell
• Vacuum Gauge

In addition to the list of commercial instruments above, Hastings developed specialized instruments for specific customers. For example: the “Ventimeter” was used by the army to measure ventilation in clothing to keep wearers comfortable under extreme weather conditions.  The Hastings Company was now growing fast and generating handsome profits for its stakeholders.

For more information on Teledyne Hastings be sure to visit our website www.teledyne-hi.com or contact us

Information for this blog was derived from “The Story of Hastings-Raydist” book by Carol Hastings Sanders 1979

Recently, I learned that certain smartphones contain an actual pressure transducer. I shared this info with a friend who insisted that the phone was not really measuring pressure, but was instead using the internet to download the pressure based on the phone’s location. Now, I had to prove them wrong.

So, I did what I thought was the obvious proof… I placed my phone in a small test chamber (i.e. a bell jar as shown in the photo below), and then pumped the system down to show that the readings were, in fact, generated locally. I captured this all on video - see below.  Note: It was hard to get a good image of the phone inside because of the protective cage surrounding the glass bell jar.

I used a free barometer app to get the pressure readings. In addition to a dial type readout, the app gives a nice trend line (pressure vs. time). Also, the app allows the user to adjust the time scale. During a recent flight, I used the app to record changes in cabin pressure. (My ears are also painfully good at detecting swings in cabin pressure!)

Now, you may be wondering why a smartphone would include a vacuum/pressure transducer. In addition to using the changing barometric pressure as an indication of weather, the pressure transducer readings can be used to provide the user’s altitude when hiking, cycling, or climbing. The formula to convert pressure to altitude at low altitudes is fairly linear. 

So, it is true that you may be able to use your smartphone to measure vacuum in your system. However, we would like to suggest an easier way… check out our new HVG-2020A (“2020 Vision”) vacuum gauge. This gauge measures from just above atmospheric pressure (1000 Torr) to below 1 Torr with an accuracy of ±(0.1% of Reading + 0.5 Torr).

The gauge features an optional color touchscreen display which has several different modes including pressure vs. time. It provides analog output (0-5 VDC, 0-10 VDC, 4-20 mA,…) as well as digital output (RS232, RS485, USB) and with our FREE Windows™ software, it is super easy to collect and store data.

For more information about any of our vacuum gauges or our complete line of mass flow meters and controllers, we are here to help. You can contact us at hastings_instruments@teledyne.com  or call 757-723-6531 (800-950-2468) or click the button below.