Understanding Pressure Measurement Errors: Tips for Accurate Transducer Readings

[can12345]

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Hello

What are the possible errors when measuring pressure value by the using a transducer? And how we can find the amount of errors?

 

[nsaspook]

What type? http://www.instrumentationtoday.com/electrical-pressure-transducers/2011/09/

 

[can12345]

Strain gauge

 

[nsaspook]

Strain gauge

I will first refer you back to here to narrow down the question: http://www.instrumentationtoday.com/strain-gauge/2011/08/

• Temperature Variation – This can be one of the major causes of error in a strain gauge. It can easily change the gauge resistance and cause differential expansion between the gauge and the test piece, causing variation in the measurable strain.
• Humidity – Humidity can affect the accuracy by the breakdown of insulation between the gauge and the ground point. It also causes electro-chemical corrosion of gauge wire due to electrolysis.
• Small errors could be caused due to thermoelectric effect.
• The gauge will be erroneous even due to small factors like zero drift, hysteresis effect and so on.
• Magnetostrictive effect can also cause errors in strain gauges of ferromagnetic materials. It produces a small voltage fluctuation of almost 2 mill volts.

The specification sheet of the transducer will usually state the variations in output due to major factors, sometimes you just have to generate calibration data at the desired environmental factors with another standard unit to check for errors.