TTNK - Current and voltage combined transformer

TTNC is a complete device, including at least 2 electronic units: one for current measurement, the second - for voltage measurement, connected to each other by a digital connection cable, high voltage columns with sensitive elements (one for each phase) connected to them via fibre optics, consisting of a reference insulator with a capacitive divider and a fibre optic current sensor installed on top of it, as well as blocks of secondary conversion of the measured signal into analogue form (delivery in a variant version).
The principle of current measurement in TTNA is based on two physical laws: the total current law and the Faraday effect. TTNA contains a sensitive element (magnetosensitive optical fibre), in which the measuring information about the current strength is converted into the phase shift of polarised radiation.