FZW32-40.5/T1250-25
Outdoor vacuum load break switch with disconnector
Outdoor vacuum load break switch with mechanically linked disconnector for three-phase 40.5 kV, 50 Hz networks. Arc interruption takes place in vacuum interrupters, and a visible isolating gap is formed on opening.
Key parameters
- Rated voltage
- 40.5 kV
- Rated current
- 1250 A
- Rated mainly active load breaking current
- 1250 A
- Rated short-time withstand current
- 25 kA (4 s)
- Mechanical endurance
- 10,000 cycles
General information
The FZW32-40.5/T1250-25 outdoor high-voltage vacuum load break switch with disconnector (hereinafter — load break switch) is a new-generation high-voltage apparatus. Following rigorous type tests and long-term trial operation, all its technical characteristics fully comply with IEC standards. It is intended for three-phase 50 Hz AC power supply networks with a rated voltage of 40.5 kV and a rated current of 1250 A.
Features
- a. Arc quenching in vacuum interrupters — no risk of explosion.
- b. The disconnector blade is mechanically linked to the three-phase vacuum interrupters — a visible isolating gap is formed on opening.
- c. All parts of the apparatus are made of stainless steel; the frame is made of stainless steel or hot-dip galvanized carbon steel with a UV-protective coating, ensuring reliable outdoor operation of the apparatus.
- d. Two-pole mounting; the main control method is electrical, manual and remote control are also possible.
- e. High switching capacity, safety and reliability, long electrical endurance, allows frequent operations.
- f. Widely used in the reconstruction and development of power lines in rural and urban networks, railways, etc.
Operating principle
The load break switch consists of two main units: the disconnector blade and the vacuum interrupter. The disconnector blade provides isolation during closing and opening, the vacuum interrupter provides arc quenching.
The disconnector blade is closed and opened by an over-centre spring mechanism. The spring supplies the energy required to close the blade and guarantees arc quenching in the vacuum interrupter during opening, regardless of the operator's actions. When the blade opens, a fast-acting mechanism provides the required opening speed of the vacuum interrupter. The three-phase common operation of the disconnector blades guarantees simultaneous opening of the vacuum interrupters.
| F | Load break switch |
| Z | Vacuum |
| W | Outdoor |
| 32 | Design serial number |
| 40.5 | Rated voltage, kV |
| T | Spring operating mechanism |
| 1250 | Rated current, A |
| 25 | Rated short-time withstand current, kA |
Service conditions
- Altitude: not more than 3000 m.
- Ambient air temperature: upper limit +40 °C, lower limit −30 °C.
- Relative humidity: daily average more than 95 %, monthly average not more than 90 %.
- No frequent severe vibration.
Main technical parameters of the load break switch
| Parameter | Unit | Value |
|---|---|---|
| Rated voltage | kV | 40.5 |
| Rated frequency | Hz | 50 |
| Rated current | A | 1250 |
| Rated mainly active load breaking current | A | 1250 |
| Rated closed-loop breaking current | A | 1250 |
| Rated 5 % active load breaking current | A | 62.5 |
| Rated cable-charging breaking current | A | 35 |
| Power-frequency withstand voltage (1 min): across the vacuum interrupter gap / phase-to-phase and to earth / across the isolating gap | kV | 68/95/110 |
| Lightning impulse withstand voltage: phase-to-phase and to earth / across the isolating gap | kV | 185/215 |
| Rated short-time withstand current (thermal) | kA | 25 |
| Rated duration of short circuit | s | 4 |
| Rated peak withstand current (dynamic) | kA | 63 |
| Rated short-circuit making current | kA | 63 |
| Mechanical endurance | cycles | 10000 |
| Permissible contact wear thickness of the vacuum interrupter | mm | 0.6 |
| Manual operating torque | N·m | ≤ 350 |
Assembly and adjustment parameters of the load break switch vacuum interrupter
| Parameter | Unit | Value |
|---|---|---|
| Contact gap | mm | 13 ± 1 |
| Three-phase contact opening non-simultaneity | ms | ≤ 20 |
| Three-phase contact closing non-simultaneity | ms | ≤ 5 |
| Clearance between live parts and to earth | mm | ≥ 420 |
| Auxiliary circuit resistance | µΩ | 400 ≥ R ≤ 1000 |
Assembly and adjustment parameters of the disconnector
| Parameter | Unit | Value |
|---|---|---|
| Disconnector blade contact pressure | N | 500 ± 50 |
| Distance from the last opening point of the moving blade to the fixed contact: small gap / large gap | mm | ≥ 180/420 |
| Resistance between input and output terminals | µΩ | ≤ 150 |