What is Calibration?

Calibration is the process of comparing the measurement output of an instrument or device with a known and accepted standard to ensure its accuracy. If there’s a difference between the measurement and the standard, adjustments are made so that the device provides correct results.

How Calibration Works (Step-by-Step)

  1. Choose a standard:
    • Use a reference instrument or material with a known value (also called a calibration standard).
    • This standard should be traceable to a national or international standard (e.g., NIST in the USA).
  2. Measure with the device:
    • Use the instrument you want to calibrate to measure the standard.
  3. Compare values:
    • Check the difference between the instrument’s reading and the standard value.
  4. Adjust (if needed):
    • If the instrument’s reading is off, adjust it to align with the standard.
  5. Document results:
    • Record calibration data and issue a calibration certificate showing the error margin, date, and technician details.

Types of Calibration

  1. Mechanical Calibration – For devices like calipers, micrometers, pressure gauges.
  2. Electrical Calibration – For voltmeters, ammeters, multimeters, oscilloscopes.
  3. Thermal Calibration – For thermometers, temperature sensors, ovens.
  4. Dimensional Calibration – For rulers, tape measures, CNC machines.
  5. Flow Calibration – For flow meters (liquid or gas).
  6. Weight Calibration – For scales and balances.