Capacitive voltage transformers of type ECF are used in high-voltage switchgears from 72 to 550 kV.  They transmit voltages to standardized, equivalent values for meters, measuring and protective devices.

The capacitive voltage transformer consists of one condenser unit and one electromagnetic measuring unit (EMU).  The condenser unit is located in the insulator and consists of one capacitive mixed dielectric which is impregnated with insulation liquid.  This active art is hermetically sealed to the outside.  For volume compensation of the oil there is a stainless steel expansion tank in the head section.  The operating pressure can be visualized via a monitoring unit.  Depending on customer specifications, creepage distance or voltage level, the condenser unit consists of up to 3 parts.  In order to avoid field distortions, a shielding electrode is used from a voltage level of 420kV.  A high-grade composite or porcelain insulator can be used as an insulator.  According to the contamination classes of common standards, different creepage distances can be selected.  The EMU is an inductive intermediate voltage transformer which is housed in the foot case of the transformer.  It allows the safe transmission of measurement signals.  A damping unit ensures increased safety against relaxation oscillation.  By using proven materials the converter is temperature and precision-stable over the entire service life.  On request, the converter can be designed in such a way that it can be used as a coupling capacitor for carrier transmission in high-voltage lines.

All metallic housings and flanges consist of a special aluminum alloy and can be painted in various colors.  The generously sized terminal box is equipped with a lid that is to be opened sideways.  This allow for easy connection of secondary cable.  The terminal box is equipped with a blind flange.  On request, cable glands or individual safety instructions can be built-in.