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What do race cars, off-highway vehicles (OHV) and any other high-performance machine or system have in common? They are only as good as the instruments you find under the hood. In fact, something as small as the pressure sensing device can have a big impact on the success or failure of meeting your equipment’s operational expectations. As an equipment builder, you expect your OEM pressure measurement instruments to be accurate. That’s a given. But even if it’s not top of mind immediately, what you want even more than accuracy is long-term repeatability. Ashcroft has been manufacturing pressure measurement instrumentation since 1852. So, we understand how challenging it can be to find high-quality, accurate and cost-effective instruments that go the distance to deliver consistent performance over the long term. This is especially relevant for sensors used in tough conditions involving exposure to wide temperature ranges, high cycle life expectations and vibration. Each of these could affect the accuracy and repeatability of critical pressure measurements. This article will explain the elements of an OEM pressure sensor, clarify the difference between repeatability and accuracy, and show you what makes a sensor accurate and repeatable over time. When you are done reading, you will know the key factors to look for when purchasing a high-performance pressure sensor for demanding cycle life conditions which can be common to many applications.

If you read my article, “Why and When is RTD Calibration Necessary?” you learned how Resistance Temperature Detectors (RTDs) such as our S81 and S50 are a better choice than thermocouples for temperature process measurement because of their repeatable, high-accuracy measurement capabilities. More specifically, RTDs are ideal for demanding applications like chemical and refining processes that depend on precise temperature measurements. But to really understand RTD calibration, you also need to know how an RTD works. When I joined Ashcroft — a leader of temperature and pressure instrument solutions across the globe— I brought more than 20 years of temperature application experience with me, and I am happy to share my knowledge with you. In the following article, you learn more about how RTDs work, the different levels of accuracy in RTD calibration and the national and international standards that they are measured against. You will also be directed to additional resources and contact information in case you are ready to take the next step in your decision to select the best temperature measurement solution for your specific application.

If you are an industrial instrument designer, you have several temperature measurement options available to you. These include Infrared, Bi-Metal, Gas-actuated thermometers, Thermistors, Thermocouples and RTDs. Industrial automation and process applications predominantly use thermocouples and Resistance Temperature Detectors (RTDs) instrumentation such as our S81 and S50 because of their proven ability to provide accurate and reliable readings. Each of these sensors has unique advantages and can be configured to match the application needs for optimum service life and performance. Based on my experience working with instrumentation and reliability teams, I’ve seen and compared the benefits of both options. Thermocouples, for example, are often chosen for a robust signal, cost-effective price and ability to withstand most process plant specifications, including harsh vibration and high-temperature range up to 2300° C. RTDs, on the other hand, are the top choice for applications demanding higher accuracy levels and minimal drift. In this article, you will learn more about the benefits of RTDs and why RTD calibration is important to maintain highly accurate and repeatable readings for a longer life span.

Heating, ventilation and air conditioning (HVAC) systems are a critical part of a building’s operation. They ensure that an indoor environment is comfortable for occupants by controlling humidity, temperature and air quality. However, the cost of running these systems can be a concern for building owners as inefficiencies in an HVAC system could increase building management costs, especially if the pressure sensors used to monitor and control the system are not accurate.

There’s a wide range of accessories for your pressure instruments that can help make your process safer, more efficient and precise. Snubbers, dampeners, capillaries, pressure limiting valves, siphons and other accessories are common additions to the most challenging applications. One question I’ve heard often during my time in this industry is: do these accessories impact the accuracy of pressure measuring instruments?