CURRENT TRANSFORMER, FOR ENERGY METERS, MODIFIED TO USE ALUMINIUM WIRE IN THE SECONDARY.

摘要

Current transformer (current sensor) for an energy meter, which main characteristic is that it has been modified for allowing aluminium wire to be used instead of copper wire that is currently used. The invention comprises a current transformer with copper wire, which is modified into a current transformer with aluminium wire for an energy meter that has the same accuracy than that of copper sensors. A minimum increase in the aluminium wire diameter has been established for obtaining an equivalent accuracy. In a similar manner, minimum size changes have been established for the transversal section of the aluminium wire, the core window and the inner and outer diameter of the core. A maximum electric resistance has also been established for winding the aluminium. Finally, a change in the window area of the rolled core is defined when the mechanical dimensions of the core are not modified. The consequence of the present invention is the use of the aluminium wire, which has a cost per ki lo 75% lower than copper, which results in substantial savings in the production of current transformers for energy meters.