Automatic calibration system for electrical sourcing and measuring instruments

Automation in measurements has extreme range of metrology applications which include instruments controlling, measurement processing and results analysing. As, commercial software is not suitable for the highly accurate metrological laboratories, the construction of an appropriate software is one of the priorities for these laboratories; consequently, a new automatic system has been established in order to control and calibrate the electrical sourcing and measuring instruments. This system has been built at the Egyptian National Institute for Standards (NIS) using Laboratory Virtual Instrument Engineering Workbench (LabVIEW) software. It is considered a coherent structure from the national electrical reference standards that can disseminate the traceability of all the instruments under calibration. The new automatic system allows large number and different models of electrical sourcing and measuring instruments to be controlled and calibrated. The system hardware is configurable by the operator on the basis of the specific calibration to be performed. The design and the implementation of the system software are discussed in details. Furthermore, the software validation has been carried out for measurements´ repeatability as well as results´ compatibility in both automatic and manual modes.