ET3H (mining version) — dry-type MV transformers up to 21 kV for explosion-protected mine substations
ET3H mining transformers are dry-type MV transformers rated up to 3 MVA for voltages up to 21 kV, for mine substations in explosion-protected design. They are supplied in IP00 version for installation in flameproof enclosures. They supply machinery and equipment of underground workings.
- Rating
- up to 3 MVA
- Voltage
- up to 21 kV (higher on request)
- Cooling
- AN, natural air
- Version
- IP00 for installation in flameproof enclosures
Price, availability and lead time on request. We help with analogue selection, customs clearance and delivery.
Description
The transformers are the main element of mine substations in explosion-protected design. Conditions in underground workings are harsh, with dust, moisture and vibration, and high temperature inside the enclosures. The ET3H is therefore designed for an explosive atmosphere, taking strict electrical safety standards into account. According to the manufacturer's catalogue, they are installed in underground flameproof transformer substations without additional cooling, although the temperature inside the enclosure often exceeds 100 °C. Cooling is natural air (AN), so increased requirements are set for the heat resistance of the winding insulation.
The operating voltage of the series is up to 21 kV, higher voltages are made at the customer's request, and the rating is up to 3 MVA. The design is adapted to underground stations, switchgear and mining equipment. The electrical and mechanical design is closely matched to customer requirements, so the manufacturer works closely with the customer at the design stage. The transformation ratio, taps, terminal positions and winding type are specified individually.
The windings, as in the other MV transformers of the plant in Lubliniec (Poland), are impregnated by the vacuum pressure method (VPI). Uniform impregnation gives a very low partial discharge level and resistance to thermal shock, condensation and contamination in class C4/E2, confirmed by certificates. The manufacturer stresses a long service life and resistance to the extreme conditions of mines, as well as lower losses and operating costs.
The transformers supply mining shearers, conveyors, pumps and fans, underground distribution points and substations, auxiliary mine infrastructure and other installations working in an explosive atmosphere. For coal and ore enterprises in Ukraine, the series is considered during modernisation of mine substations as a replacement for dry-type transformers of post-Soviet manufacture. Selection is based on voltage, rating and the dimensions of the existing enclosure.
Every transformer undergoes routine tests at the plant on an MV test station rated up to 5 MVA, including partial discharge measurement in a shielded chamber that cuts off external interference, and a lightning impulse test. The enquiry should state the rating, primary and secondary voltage, transformation ratio, taps and terminal positions for the specific enclosure. Versions with parameters outside the catalogue are made by agreement.
Technical specifications
| Rating | up to 3 MVA |
|---|---|
| Voltage | up to 21 kV (higher on request) |
| Cooling | AN, natural air |
| Version | IP00 for installation in flameproof enclosures |
| Temperature inside the enclosure | often above 100 °C (per the catalogue) |
| Impregnation | VPI, class C4/E2 |
| Parameters to order | transformation ratio, taps, terminal positions, winding type |
Replacement for
ТСВП-400/6, ТСВП-630/6, ТСВП-1000/6, ТСШВП-250/6 (mine explosion-proof), КТПВ-…/6; no direct analogue at 10–21 kV
selected by purpose and main parameters, please confirm with our manager
Request a price and lead time
ET3H (mining version) — dry-type MV transformers up to 21 kV for explosion-protected mine substations. We reply within one business day.
Or email sales@usk.ua or call 044 339-50-20.
Questions and answers
What are the rating and voltage of the ET3H mining transformers?
Rating up to 3 MVA, operating voltage up to 21 kV, with higher voltages made at the customer's request. Cooling is natural air AN.
How is the transformer installed in an explosion-protected substation?
The transformer is supplied in IP00 version and installed in a flameproof enclosure of an underground substation without additional cooling. The temperature inside the enclosure often exceeds 100 °C.
What tests does each transformer undergo?
Routine tests on an MV station rated up to 5 MVA, including partial discharge measurement in a shielded chamber and a lightning impulse test.
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