Capacitive Voltage Transformer ECF
Voltage transformers type ECF are used in high voltage networks within the 72-550 kV range. They transform high voltage into standardised values for meters, measuring and protection 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 part is hermetically sealed to the outside. For volume compensation of the oil there is a stainless steel expansion bellows in the head section. The operating pressure can be visualized via a monitoring unit. Depending on customer specification, 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 420 kv. A high-grade composite or porcelain insulator can be used as 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 voltage transformer is temperature- and accuracy stable over the entire service life. On request, the voltage transformer 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 aluminium alloy and can be painted in various colours. The generously sized terminal box is equipped with a cover that is to be opened sideways. This allows for easy connection of secondary cables. The terminal box is equipped with a flange without holes. On request, cable glands or individual safety devices can be built in.
Features
- Cost-effective and reliable Design for high and very high voltages
- Expandable for the transmission of high-frequency Signals (TFH)
- Fabrication-internal adjustment of the accuracy classes, no on-site adjustment is required
- Temperature- and accuracy stable over the entire service life
- Increased safety against relaxation oscillation due to damping unit
Specifications and Downloads
Technical Specifications
Dimensions
Technical data
Type ECF | 72 | 123 | 145 | 170 | 245 | 300 | 362 | 420 | 550 | |
Standard | IEC / IEEE | |||||||||
Highest voltage for equipment | kV | 72.5 | 123 | 145 | 170 | 245 | 300 | 362 | 420 | 550 |
Rated power-frequency withstand voltage | kV | 140 | 230 | 275 | 325 | 460 | 460 | 510 | 630 | 680 |
Rated lightning impulse withstand voltage | kV | 325 | 550 | 650 | 750 | 1050 | 1050 | 1175 | 1425 | 1550 |
Frequency | Hz | 50 / 60 | ||||||||
Accuracy class | 0.1-3; 3P; 6P | |||||||||
Rated thermal limiting output VT part | VA | ≤ 1000 | ||||||||
Max. simultaneous burden (cl. 0.2) | VA | 150 | ||||||||
Max. number of VT windings | 5 |
Type ECF | 72 | 123 | 145 | 170 | 245 | 300 | 362 | 420 | 550 | ||
Height of unit* | A | mm | 1660 | 1930 | 2130 | 2330 | 2930 | 3310 | 3510 | 4310 | 5110 |
Height to primary terminal* | B | mm | 1520 | 1790 | 1990 | 2190 | 2790 | 3170 | 3370 | 4170 | 4970 |
Depth of unit including terminal box | C | mm | 746 | 746 | 746 | 746 | 746 | 746 | 746 | 746 | 746 |
Depth of unit base | D | mm | 500 | 500 | 500 | 500 | 500 | 500 | 500 | 500 | 500 |
Width of unit base | E | mm | 500 | 500 | 500 | 500 | 500 | 500 | 500 | 500 | 500 |
Distance between screw holes at base | F | mm | 450 | 450 | 450 | 450 | 450 | 450 | 450 | 450 | 450 |
Min. creepage distance* |
| mm | 2420 | 3540 | 4280 | 5030 | 7260 | 7820 | 8560 | 11540 | 14520 |
Approximate weight* |
| kg | 280 | 300 | 320 | 340 | 400 | 420 | 450 | 500 | 540 |
*with standard composite silicone insulator, creepage distance 25 mm/kV