1.** Classification by application field: * *
-Electrical category: including resistance box, multimeter, oscilloscope and other electronic measuring equipment.
-Mechanical category: including micrometer, vernier caliper, coordinate measuring machine and other mechanical measuring equipment.
-Chemistry: including chemical analysis equipment such as acidity meter, chromatograph and photometer.
-Physics: including thermometers, manometers, balances and other physical measuring equipment.
2.** Classification by calibration object: * *
-Electrical signals: such as voltage, current, resistance, etc.
-Mechanical quantities: such as length, angle, pressure, etc.
-Optical parameters: such as light intensity, wavelength, etc.
-Chemical parameters: such as pH value, concentration, etc.
3.** Classification by calibration purpose: * *
-Precision calibration: to verify the accuracy and precision of the instrument.
-Debugging and calibration: debugging newly purchased or maintained instruments.
-Acceptance calibration: after purchase or maintenance, verify whether the instrument meets the specified standards.
-Traceability calibration: Traceability of instrument calibration results to national or international standards.
4.** Classification by calibration method: * *
-External inspection method: the error of the calibrated instrument is determined by comparing with the standard instrument.
-Internal detection method: use self-calibration function or internal calibration source to calibrate the instrument.
Comparison method: Calibration by comparison with reference instruments with known accuracy.
These classification methods are helpful to determine the specific categories and processes of calibration and testing of different types of measuring instruments, and ensure the accuracy and reliability of the instruments.