Product Overview
GW4-126/3150A outdoor double-column horizontal-opening high-voltage disconnectoris suitable for 110 kV three-phase AC 50 Hz power systems, for opening and closing circuits under no-load conditions and for electrical isolation of equipment under maintenance from live lines. The product has a rated voltage of 126 kV and a rated current of 3150 A; it is of double-column horizontal-opening type with optional double earthing switches, with a large conducting cross-section and low temperature rise, suitable for incoming and outgoing lines of high-current substations. Hot-dip galvanizing is applied for corrosion protection; rotating parts that cannot be guaranteed by hot-dip galvanizing generally use stainless steel, fasteners below M8 are stainless steel and the rest are hot-dip galvanized. The conductive part is of copper-tube flexible-connection type; the intermediate contacts are “handshake” self-supported contact fingers with externally pressed springs carrying no current - the disconnector has only one central contact point while the rest are fixed flexible connections. The new contact structure fixes one end of the contact strips to the contact seat; the contact pressure is produced by strip deformation and springs, changing the sliding contact at the finger ends into fixed contact and improving conduction reliability; the finger springs are externally mounted to avoid spring shunting; magnetic lock plates are added to improve dynamic and thermal stability. The rotating parts are fitted with self-lubricating sleeves requiring no grease. The main terminals are flat type. For 630 A the conductive parts are tin-plated; for 1250 A-4000 A they are silver-plated. The upper and lower caps of the porcelain insulators are hot-dip galvanized for rust prevention; insulators with different creepage distances can be selected per the pollution level of the service area; positive tolerance is applied in manufacturing and the creepage distance is designed above the standard value. The post insulators have high strength density and are stable and reliable; the formula uses high-strength materials to reduce strength dispersion and increase tensile strength, and a large strength margin is reserved in the structural design to ensure stable and reliable operation.
Structural Features
The 110kV complete disconnector consists of the GW4-126（D）（W） disconnector body, CS11 or CS8-6D manual operating mechanism and transmission accessories; CJ6 motor-driven mechanisms can also be fitted. This disconnector is of double-column horizontal-opening type, made in single-pole form; when three poles are used in synchronism, the poles are connected by connecting rods. Each single pole consists of the base, post insulators, outgoing terminals and contacts; the two post insulators are mounted in parallel on the bearings at both ends of the base, perpendicular to it. The main conducting parts are mounted on top of the two post insulators and rotate about 90° with them. Each bearing housing contains a shaft assembly, and the two shaft assemblies are connected and driven through connecting plates and adjusting screws. The copper braided flexible connections in the outgoing terminals are fixed to the conductive tubes and terminal plates, which are for user line connection. The intermediate contact fingers are installed in pairs, of self-supported type in plug-in form, reducing the wear between contacts and fingers during opening/closing and extending service life. When the disconnector is fitted with earthing switches, the interlock between the main circuit and the earthing switch is ensured by the sector plate and arc plate on the base: when the main circuit is closed the earthing switch cannot be closed, and when the earthing switch is closed the main circuit cannot be closed. When CS8-6D is used, the interlock between the disconnector and the earthing switch is realized by the interlock plate on the mechanism.
Main Technical Parameters
| No. | Item | Unit | Parameter (GW4-126/3150) |
|---|---|---|---|
| 01 | Rated voltage | kV | 126 |
| 02 | 1-min power-frequency withstand voltage | to earth kV | 230 |
| across break kV | 245 | ||
| 03 | Lightning impulse withstand voltage (peak) | to earth kV | 550 |
| across break kV | 630 | ||
| 04 | Rated frequency | Hz | 50 |
| 05 | Rated current | A | 3150 (4000 available in the same series) |
| 06 | Rated short-time withstand current | kA | 50 (for 3150A rating) |
| 07 | Rated peak withstand current | kA | 125 |
| 08 | Rated short-circuit duration main blade/earthing blade | s | 4/2 |
| 09 | Rated terminal mechanical load | Horizontal longitudinal N | 1000 |
| Horizontal transverse N | 750 | ||
| Vertical force N | 1000 | ||
| 10 | Creepage distance | mm | 3150-3900 |
| 11 | Mechanical life | operations | 2000 |
| 12 | Manual operating mechanism | Without earthing | CS11(F) |
| With earthing | CS8-6D(F) / main blade CS14G(F), earthing blade CS11(F) | ||
| 13 | Motorized operating mechanism | Model / motor voltage | CJ6 / AC380 |
| Opening/closing time | 6±1 s | ||
| 14 | Product weight | Without earthing kg | 700 |
| Single earthing kg | 800 | ||
| Double earthing kg | 900 |
Outline & Installation Dimensions
Product photo and installation drawing of the GW4-126 (DW) outdoor high-voltage disconnector
Structure: 1 base, 2 post insulator, 3 terminal, 4 fixed conductive tube, 5 waterproof cover, 6 moving conductive tube. The GW4-126/3150A outdoor double-column horizontal-opening high-voltage disconnector consists of the above base, post insulators, fixed and moving conductive tubes and other parts, simple in structure and easy to maintain.
Service Conditions
① Ambient temperature: upper limit +40℃, lower limit -30℃ (special order for frigid regions); ② Altitude: not exceeding 1000 m (above 1000 m the insulation level may be corrected per GB311.1); ③ Wind speed: not more than 35 m/s; ④ Ice thickness: not more than 10 mm; ⑤ Seismic intensity: not exceeding degree 8; ⑥ The site shall be free of flammable, explosive, heavy dust, chemical corrosion and violent vibration. The GW4-126/3150A outdoor double-column horizontal-opening high-voltage disconnector maintains flexible operation and reliable isolation for a long time under the above normal service conditions.
Related Products
High-voltage disconnectors of the same series and other types available:
- GW4-40.5/630A outdoor double-column horizontal-opening high-voltage disconnector
- GW4-72.5/1250A outdoor double-column horizontal-opening high-voltage disconnector
- GW4-110/1250A outdoor double-column horizontal-opening high-voltage disconnector
- GW5 series V-type outdoor high-voltage disconnector
- GW9-12 single-phase outdoor high-voltage disconnector
- GW13 series neutral-point outdoor high-voltage disconnector
