High voltage power metering box (without an electricity meter, called combined transformer) AC oil-immersed outdoor type (also suitable for indoor), is a metering device for direct measurement of active and reactive power in high voltage lines. Suitable for three-phase AC 35kV.10kV. 6kV. 3kV power system network with rated frequency S0Hz and 60Hz.It has the advantages of high precision, light weight, convenient installation and anti-electric larceny, etc., and is welcomed by the general power supply departments, which plays an important role in preventing electric larceny, saving energy and strengthening power supply management.