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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 asCURRENT
• Resistor values are inOHMS(Ω is the symbol for ohms)
• VOLTAGEis the result of passing amps through a resistor

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.

The accuracy ofdifferential pressure transducershas greatly improved to provide better solutions for demanding applications. This article discusses why accuracy is an important consideration when selecting a pressure transducer for low-differential, critical pressure applications.

Total Error Band (TEB) is a measurement ofworst case error; it is the most comprehensive and concise measurement of a sensors true accuracy over a compensated temperature range. TEB is extremely important to know when trying to determine how well a sensor will work within a particular design system. By calculating TEB you'll be able to understand the different possibilities for error. Formulating TEB can be tricky if you don't have the right inputs readily available.

Any design engineer must seriously consider the manufacturing environment when looking to select apressure transducerfor inclusion within a refrigeration chiller, pump,engine test equipment, or other machinery. The life of a pressure transducer is proportional to the system design and assembly process.

Which method provides better accuracy? Non-linearity as theEnd Point Methodis the relationship of the calibration curve to a specified straight line through its endpoints (i.e. Zero and Full Scale).Best Fit Straight Line (BFSL)method is the relationship of the calibration curve to a calculated straight line that minimizes the error but does not pass through the end points. BFSL method effectively cuts the end point value in half.

Many of the following technical specifications appear on datasheets for pressure transducers and similar devices. Here we review their technical definitions and relationships.

Root Sum Squares (RSS):accuracy of apressure transduceris calculated by taking the square root of non-linearity + hysteresis + non-repeatability.

Shock & vibration are two potential mechanical problems for pressure transducers.

Shock is a sudden, unexpected impact that transmits energy to a device in a relatively short time interval. For a pressure transducer, that energy passes through the stainless steel up through the housing. Shock may originate from rough transportation and handling, such as by trucks, forklifts and conveyors. Alternately, shock can be caused simply by dropping the transducer on the shop floor or by an assembler slamming a cabinet door adjacent to it. Atransducermay not be damaged by a single shock, but can experience fatigue failure with numerous low-level shocks over the course of its life.

Capacitance based pressure transducers provide many benefits over other technologies. 8 features that should be considered when choosing apressure transducerare accuracy, minimal mechanical motion, range capabilities, long term stability, high-level output, media compatibility, electromagnetic compatibility and resistant to harsh environments..

我们经常听到用于描述压力传感器的术语或在HVAC/R和工业工业中常用的术语，但它们的含义可能会有一些混淆。以下是一些常用的术语及其定义。