Measurement Specialties CIO-SSH16 user manual Smoothing Data

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6.9.4 SMOOTHING DATA

It is not always possible to eliminate all noise, especially with very low level sensors, but noise looks terrible when plotted and can raise doubts about otherwise excellent data. There are two simple ways to eliminate noise from the data:

1.Apply a moving average to the data if you want to retain the same apparent accuracy.

2.Remove the information from the noisy range. For example, if a 12 bit A/D converter is at +/- 5 volts (10 volts full scale) then one LSB = 10 / 4096 = 0.00244mV. If your system is inducing +/- 0.007mV of noise (+/- 3 counts), round all the readings by +/- 3 counts. In this way the reading's value reflects the true accuracy of the system.

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Contents CIO-SSH16 Copyright 2000 Measurement Computing Corp Adding Amplifiers & Sample / Hold Chips This page is blank Introduction Software InstallationHardware Installation Power Cable Power Connector Signal CableGain Switches Analog Input Board SetupConnector Diagram Signal ConnectionAnalog Inputs Floating DifferentialExample DifferentialPage Amplification ArchitectureAnalog Input CIO-SSH16 vs. Programmable Gain A/D Boards Sample & Hold S15 S16 Droop Rate Sample and Hold Timing DiagramAdding Amplifiers Sample / Hold Chips Resolution CalculationRange Calculation Time to Sample CalculationAnalog input section SpecificationsSample / hold section Voltage Dividers Analog ElectronicsPage Differential & Single Ended Inputs Common Mode RangePage LOW Pass Filters Common MisunderstandingsGround Loops Converter # Volts A/D Resolution & Engineering UnitsCurrent Loop 4-20 mA Engineering UnitsSources of Noise NoiseSensor Noise Signal Wire NoiseSmoothing Data For your notes EC Declaration of Conformity