GW4-27.5/1250D Earthing Switch (27.5kV)
GW4-27.5/1250D outdoor HV disconnector with integrated earthing blade, 27.5kV 1250A, per GB 1985-2014.
Specifications
| Model | GW4-27.5/1250D |
|---|---|
| Standard | GB 1985-2014 HV AC disconnectors and earthing switches; TB/T railway industry standards |
| Rated Voltage | 27.5kV |
| Design Speed | N/A (fixed installation equipment) |
| Operating Temperature | -40°C to +70°C |
| Altitude | ≤ 4,000 m |
| Materials | Hot-dip galvanized steel frame; copper alloy contacts; high-strength post insulators |
| Installation | Pole-side or independent foundation mounting; manual / motorized / hand-crank operating mechanisms |
The GW4-27.5/1250D is an outdoor high-voltage disconnector rated 27.5kV with an integrated earthing blade. It is designed for maintenance earthing scenarios on electrified railway catenary and substations: after isolating the circuit, the earthing blade grounds the dead side so crews can work safely.
Mechanical interlocking between the main blade and the earthing blade prevents incorrect operating sequences, raising on-site safety. The switch is built per GB 1985-2014 and TB/T railway industry standards with a hot-dip galvanized steel frame, copper alloy contacts and high-strength post insulators, rated for -40°C to +70°C and altitudes up to 4,000 m.
Installation is pole-side or on independent foundations, with manual, motorized or hand-crank operating mechanisms available.
Contact Henan Chuangwit Railway Equipment Co., Ltd. for datasheets and project support.
Frequently Asked Questions
What is the earthing blade for?
After the main blade isolates the circuit, the earthing blade grounds the de-energized side, protecting maintenance crews against induced voltage and accidental re-energization.
How is wrong operation prevented?
A mechanical interlock between main and earthing blades enforces the correct operating sequence — the earthing blade cannot close while the main blade is closed, and vice versa.
Which standard applies?
GB 1985-2014 (HV AC disconnectors and earthing switches) plus TB/T railway industry standards.
Performance
Operating Conditions
Outdoor traction power service from -40°C to +70°C, altitudes to 4,000 m, including polluted and humid environments.
Mechanical Performance
GW4 platform with integrated earthing blade and mechanical interlock enforcing safe operating sequences.
Electrical Performance
27.5kV isolation with maintenance earthing capability per GB 1985-2014 for railway catenary and substations.
Applications
Maintenance Earthing
Ground the dead side before crew access.
Catenary Isolation
Section isolation with integrated earthing.
Outdoor Service
Galvanized structure for open-air duty.
Cold Regions
Operation down to -40°C.
