Setra Blog

Until recently, there was no standard industry network protocol for building automation, and users had to choose between many different systems from different manufacturers. Proprietary communications were a result of no off-the shelf communication solution.

Today, we have reached a place where there are three inter-operable standard network protocols to choose from: BACnet, LonWorks and Modbus. All three are widely used, and according to a Building Operating Management survey in 2011, 62% of respondents had at least one BACnet application; for LonWorks the percentage was 40%, while for Modbus the number was 30%.

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).

Pressure Transmitter, Transducer, Sensor, or Switch: What are they and how are they different from each other?

The pressure sensing industry features a variety of devices, and their names can be confusing to those unfamiliar with the terminology. 

Setra's MR Series features a lineup of cutting-edge pressure transducers designed for HVAC applications. From the adaptable MR1 and MR2 to the high-performance MRG and versatile MRC, each product in this series combines multi-range capabilities with top-tier performance. In this article, we'll delve into the features and advantages of these sensors, showcasing why they're the go-to choice for contractors looking for reliability, flexibility, and precision in their HVAC applications.

MR1 (Low Range)

The Setra MR1 is the ideal product for any contractor, combining the flexibility of a multi-range with the performance of a single range sensor. The MR1 has 8 selectable ranges (0.1, 0.25, 0.5, and 1.0” W.C.) and 3 selectable outputs, easily adjustable on the job with a flip of a switch or jumper. The MR1 uses an IP67/NEMA 4-rated housing and has a conduit fitting for easy wiring, making the MR1 an ideal solution for any general HVAC application.

MR2 (High Range)

The Setra MR2 stands out as the perfect choice for contractors, merging the versatility of a multi-range sensor with the efficiency of a single range sensor. With 8 selectable ranges (1.0, 2.5, 5.0, and 10” W.C.) and 3 selectable outputs, it's effortlessly adaptable on-site with a simple switch or jumper adjustment. Encased in an IP67/NEMA 4-rated housing and featuring a conduit fitting for straightforward wiring, the MR2 is an excellent fit for various general HVAC applications.

Setra Systems will be exhibiting at the AHR Expo in Las Vegas from January 31 through February 2. In addition to our extensive HVAC and Critical Environments lines, this year Setra will be unveiling several new and exciting products. Come by and see Setra at booth C5712!

Throughout the entire HVAC field, there are a variety of applications that use differential pressure transducers. With rugged stainless-steel housing, an isolated electrode, and a stainless-steel diaphragm, Setra’s sensors can be used in several of these applications.

Converting mA to voltage is common in HVAC when working with pressure transducers. Terminology to keep in mind includes:

• 1 mA = 0.001 AMP (short for amperes)
• Amps are referred to as CURRENT
• Resistor values are in OHMS (Ω is the symbol for ohms)
• VOLTAGE is the result of passing amps through a resistor

A variety of pressure sensor designs are available today. Two of the most common sensor types are MEMS and capacitive sensors.

Until recently, there was no standard industry network protocol for building automation, and users had to choose between many different systems from different manufacturers. Proprietary communications were a result of no off-the shelf communication solution. Today, we have reached a place where there are three inter-operable standard network protocols to choose from: BACnet, LonWorks and Modbus. All three are widely used, and according to a Building Operating Management survey in 2011, 62% of respondents had at least one BACnet application; for LonWorks the percentage was 40%, while for Modbus the number was 30%.

In HVAC and refrigeration, pressure sensors monitor pressure changes to indicate when issues arise. Drops in pressure can alert technicians of needed maintenance or larger problems. Within the variety of HVAC applications are also numerous available sensors for every environment. For example, industrial pressure sensors can be used to measure the pressure of fluorocarbon refrigerants, the pressure of chilled water in chiller systems, or the pressure of refrigerant in a refrigeration system.