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"An unpolarized light beam will change to a linear polarized beam by using a polarizing filter. In turn the linear polarized beam can be rotated in an active medium such as glass if a magnetic field exists. This phenomenon, which is known as Faraday effect, is there for can used as a current sensor. In this experiment, the current to be measured was flowed in Helmohltz coils where a homogeneous magnetic field was generated. Bismuth and Flumbo alloys were used as glass medium. An analyzer detected the linear polarized beam came from the glass. The analyzer was adjustable and has a capability to detect a light signal up to 1 mill radian per degree. The values of the rotation of the polarized light beams in the active medium were determined by Verdet's constant. The characteristics of the glasses were represented by plotted curves of rotation angle versus the wavelengths of the light beam, which shows parabolic form. The sensing current by Faraday effect shows a linear feature of rotation angle with respects to the current value, as predicted by the theory. The result also shows that the glass of Bismuth alloy is more sensitive than the Plumbo alloy."

"Currently, three single junction–type Thermal Voltage Converter (TVC) standard units represent the highest standard of AC (Alternating Current) voltages owned by the Electrical Metrology Laboratory, Research Centre for Metrology—Indonesian Institute of Sciences. The accuracy of the single junction–type TVC is maintained regularly via intercomparison processes using a one-step build-up and build-down method. To reduce the calibration process quantity, three steps of build-up and build-down measurements that refer to the 4 V measurement point of a HOLT production single junction–type TVC were carried out. The dissemination processes with the best measurement accuracy up to 20 ppm were successfully obtained from measurement points between 1 V and 20 V via 4–1V, 4–2V, 4–3V, 4–6V, 4–10V, and 4–20V formations."