need of calibration and explain the procedure to calibrate the instrument.

need of calibration and explain the procedure to calibrate the instrument.
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1 Answer

Answer :

Need of calibration: Every measuring device degrades over time due to normal wear and tear. These changes can be caused by various reasons such as electric or mechanical shock or a hazardous manufacturing environment. In those situations, calibration is required to perform on those instruments to enhance the accuracy of the measuring device. Accurate measuring devices increase product quality. Here are the five reasons, why calibrating instruments is important:


• Making sure that the instrument is making consistent measurements and displaying the correct readings.

• Establishing the instrument’s reliability

• Maintaining adherence to industry standards, government regulations, and/ or quality assurance norms like the current good manufacturing practice.

• Determining the precision, deviation, and reliability of the measurements


Procedure to calibration instrument: A calibration can take advantage of a wide range of different principles. By measuring different properties of the object under calibration it is possible to perform a calibration. This can result in different calibration methods for the same measurand, often also on the same object under calibration. It is possible to perform; direct or indirect calibrations depending on which property of the object under calibration are to be determined.


Direct method: Calibration of the shunt via measurement of the resistance value.


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Indirect method: Calibration of the shunt via measurement of the currents under applied voltage the resulting different magnitude are used to calculate the resistance based on ohm’s law.


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