8DN8 / 8DN9 — SF6 GIS 72.5–245 kV (offshore up to 300 kV)
8DN8 and 8DN9 are SF6 gas-insulated switchgear (GIS) of the 8D series for 72.5–245 kV substations. The 8DN9 operates up to 300 kV at offshore substations. The switchgear is installed at urban and industrial substations with limited space, at power plants and wind farms, and in polluted or difficult climatic environments.
- Rated voltage
- 8DN8: up to 145/170 kV; 8DN9: up to 245 kV (offshore up to 300 kV)
- Short-circuit breaking current
- 8DN8: up to 40 kA (145 kV) / 63 kA (170 kV); 8DN9: up to 50 kA
- Rated busbar and feeder current
- 8DN8: up to 3150/4000 A; 8DN9: up to 4000 A
- Test voltage (8DN8)
- 275/325 kV, lightning impulse 650/750 kV
Price, availability and lead time on request. We help with analogue selection, customs clearance and delivery.
Description
The 8D series has been built since 1968. According to the manufacturer, more than 24,000 bays are installed worldwide, with a total operating experience of over 285,000 bay-years. Insulation and arc extinction are provided by SF6. The breakers work on the self-compression principle and have a spring-operated mechanism, that is, they use the same modules as the 3AP live tank breakers.
The 8DN8 is rated for voltages up to 145 kV with a breaking current of up to 40 kA and a rated busbar and feeder current of up to 3150 A. The version up to 170 kV gives 63 kA and 4000 A. The power-frequency test voltage is 275/325 kV, the lightning impulse 650/750 kV, and the peak withstand current 108/170 kA. The break time is less than 3 cycles, and the auto-reclosing cycle is O-0.3 s-CO-3 min-CO. A bay 800 mm wide (145 kV) weighs about 3 t, and a bay 1000 mm wide (170 kV) about 4.7 t. Depth and height depend on the layout and are approximately 2.6×4.1 m and 3.2×5.5 m. For the 8DN8 at 145 and 170 kV, low-power instrument transformers LPIT are offered, which shorten the bay length.
The 8DN9 is intended for networks up to 245 kV. According to the manufacturer's summary table, it is rated for a breaking current of up to 50 kA and rated currents of up to 4000 A.
Both series allow indoor and outdoor installation at −30…+55 °C, and the control circuits are supplied from 48–250 V DC. Gas leakage is below 0.1 % per year per gas compartment. The first major overhaul is needed no earlier than after 25 years, and the expected service life is over 50 years. The local control cabinets combine control of the breaker, disconnectors, earthing switches and fast-acting earthing switches, lockout on gas loss, and density sensors. Controlled switching systems and Sensgear monitoring are connected to them.
The GIS comply with IEC, IEEE and GOST standards. Production is located in Germany (Berlin), and there are also plants in China and India.
Technical specifications
| Rated voltage | 8DN8: up to 145/170 kV; 8DN9: up to 245 kV (offshore up to 300 kV) |
|---|---|
| Short-circuit breaking current | 8DN8: up to 40 kA (145 kV) / 63 kA (170 kV); 8DN9: up to 50 kA |
| Rated busbar and feeder current | 8DN8: up to 3150/4000 A; 8DN9: up to 4000 A |
| Test voltage (8DN8) | 275/325 kV, lightning impulse 650/750 kV |
| Break time | < 3 cycles |
| Bay width (8DN8) | 800 mm (145 kV), 1000 mm (170 kV) |
| Bay weight (8DN8) | 3 t / 4.7 t |
| Gas leakage | < 0.1 % per year per compartment |
| First major overhaul / service life | > 25 years / > 50 years |
| Standards | IEC, IEEE, GOST |
Request a price and lead time
8DN8 / 8DN9 — SF6 GIS 72.5–245 kV (offshore up to 300 kV). We reply within one business day.
Or email sales@usk.ua or call 044 339-50-20.
Customs codes
| UKTZED (Ukraine) | 8537 20 99 00 |
|---|---|
| HS, 6 digits | 8537 20 |
| CN (EU) | 8537 20 99 |
| HTSUS (USA) | 8537 20 00 00 |
| China customs tariff | 8537 20 11 00 8537 20 19 00 |
Codes are for reference: the final code is determined at declaration for the specific model.
Questions and answers
Which 8D series GIS should be chosen for a 245 kV substation?
For networks up to 245 kV the 8DN9 is intended, with a breaking current of up to 50 kA and a rated current of up to 4000 A. The 8DN8 is rated only up to 170 kV.
What are the footprint and weight of an 8DN8 bay?
The 145 kV bay is 800 mm wide and weighs about 3 t, and the 170 kV bay is 1000 mm wide and weighs about 4.7 t. Depth and height are approximately 2.6×4.1 m and 3.2×5.5 m depending on the layout.
Can the 8DN8 be installed outdoors?
Yes, indoor and outdoor installation is permitted in the range −30…+55 °C. Gas leakage is below 0.1 % per year per compartment.
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