Search results
Results from the WOW.Com Content Network
The formal definition of calibration by the International Bureau of Weights and Measures (BIPM) is the following: "Operation that, under specified conditions, in a first step, establishes a relation between the quantity values with measurement uncertainties provided by measurement standards and corresponding indications with associated measurement uncertainties (of the calibrated instrument or ...
Metrology is defined as the science of weights & measures, while a PMEL is the place where technicians perform all of the metrology for the U.S. Air Force. Air personnel in this career field are primarily responsible for the repair, calibration, and modification of test, measurement, and diagnostic equipment (TMDE), including precision ...
Commercial scales have to be National Type Evaluation Program (NTEP) approved or certified. The certification is issued by the National Conference on Weights and Measures (NCWM), in accordance to the National Institute of Standards and Technology (NIST), "Handbook 44" specifications and tolerances, [1] through Conformity Assessment and the Verified Conformity Assessment Program (VCAP) [2]
ISO/IEC 17025 General requirements for the competence of testing and calibration laboratories is the main standard used by testing and calibration laboratories. In most countries, ISO/IEC 17025 is the standard for which most labs must hold accreditation in order to be deemed technically competent.
For example, in the case of a 60 tonne load cell, then specific test weights that measure in 5, 10, 20, 40 and 60 tonne increments may be used; a five step calibration process is usually sufficient for ensuring a device is accurately calibrated. Repeating this five-step calibration procedure 2-3 times is recommended for consistent results. [16]
The Articles of Confederation, ratified by the colonies in 1781, provided: . The United States in Congress assembled shall also have the sole and exclusive right and power of regulating the alloy and value of coin struck by their own authority, or by that of the respective states—fixing the standards of weights and measures throughout the United States.
Calibration laboratories are accredited and provide calibration services to industry firms, which provides a traceability link back to the national metrology institute. Since the calibration laboratories are accredited, they give companies a traceability link to national metrology standards. [2]
A dead weight tester (DWT) is a calibration standard method that uses a piston cylinder on which a load is placed to make an equilibrium with an applied pressure underneath the piston. Deadweight testers are secondary standards which means that the pressure measured by a deadweight tester is defined through other quantities: length, mass and time.