Setra Blog

Many electricians and contractors are moving towards using Rogowski Coils because of the time saved during installation and the reduced shipping costs for high amperage requirements. Because of the size, weight and flexibility of a Rogowski Coil, installers can save significant time and labor because of the ease of surrounding conductors of all sizes. However, what most people don’t realize is that Rogowski Coils have many technical advantages over standard split-core or “donut” CT’s which can help improve monitoring energy in different applications.

Thank you to all who visited us at Booth C1452 in the Building Automation and Controls section of the AHR Expo this year in Las Vegas, Nevada! We enjoyed seeing both new and familar faces! The world's largest HVACR event was anything but boring and we think the 60,000 attendees would have to agree.

Barometric altimeters calculate and display altitude by measuring the local barometric pressure and converting that measurement into altitude. This conversion is done using the Standard Atmosphere Table, an international standard representing the barometric pressure at various altitudes on a so-called "standard day" which assumes a consistent non-linear relationship between altitude and pressure.

Transducers are used across many applications to provide accurate, real-time data of how a system is working. Calibration is critical to maintaining a pressure transducer’s accuracy and it is not a one-time process. All pressure transducers used in critical applications should be regularly calibrated to maintain high performance. If a transducer drifts out of its specified pressure range, it can lead to false pressure readings causing decreased equipment performance and possible safety concerns. Calibration allows the user to be completely confident that their transducers are correctly performing and measuring the required pressure range accurately.

So, how often should you calibrate a pressure transducer? It is a common question we get asked all the time. Pressure transducers should be calibrated as often as needed in order to, maintain the necessary accuracy for the application. The amount of calibration required by the transducer can vary based on factors, such as the application and the transducer’s stability

After clarifying the different types of pressure measurements and the difference between absolute and gauge, it is time to expand and discuss the two types of gauge pressure; vented gauge and sealed gauge reference pressure.

1. Pressure

The first and most important consideration is pressure. A number of questions must be answered to ensure the correct transducer is selected. What is the pressure range that the transducer will measure? What is the maximum pressure the transducer will encounter? What is the potential for over pressure in the system?

When installing a pressure transducer system, selecting a power supply may not be one of the first things that comes to your mind. Since a single power supply can be used to power multiple pressure transducers, many regard it as a non-vital task. Nonetheless, it is essential to have the proper configurations between the power source and devices in order for all components to communicate properly and to avoid receiving inaccurate data. Here are some of the best practices we found for using a single power supply to power multiple devices.

In HVAC/R applications it is helpful to understand the methods used to determine air velocity. Air velocity (distance traveled per unit of time) is most often expressed in feet per minute (FPM).  Multiplying air velocity by the area of a duct allows you to determine the air volume flowing past a point in the duct per unit of time. Volume flow is generally measured in cubic feet per minute (CFM).

Unidirectional Pressure Transducers

Unidirectional pressure transducers measure between zero and a positive pressure. The diaphragm of the sensor should only move in one direction and will produce a positive voltage or milliamp output.

Pressure transducers today are more rugged and reliable than ever. Made of stainless steel construction, they provide abundant overpressure protection, improved total error band, and offer negligible orientation and vibration effects. They are ideal for long-term use even in harsh environments of extreme temperature, humidity, and vibration.