Compact, highly conductive isolators designed for integration into medium-voltage metal-enclosed switchgear. Providing an undeniable visible isolation gap for safe panel maintenance.
An Indoor Disconnector Switch (or Isolator) is a mechanical switching device installed exclusively inside metal-enclosed switchgear cabinets. Its primary function is to physically isolate downstream equipment from the power source, creating a visible isolation gap that operators can verify with their own eyes before commencing maintenance.
Safety Warning: Indoor disconnectors are “No-Load” switches. They do not possess arc-quenching chambers. They must only be operated (opened or closed) after the main circuit breaker has safely interrupted the load or fault current. Operating an isolator under load will cause a catastrophic electrical arc inside the cabinet.
The conductive blades are mounted on premium APG epoxy resin post insulators. These insulators offer high dielectric strength, excellent resistance to condensation, and prevent tracking within the confined space of a switchgear cabinet.
To handle high continuous currents (up to 4000A) without overheating, the stationary and moving contacts are forged from T2 pure copper and heavily silver-plated to ensure minimal contact resistance and prevent oxidation.
Most indoor disconnectors (like the GN30 series) can be equipped with a built-in earthing switch on the load side. This compacts the overall footprint and allows for seamless mechanical interlocking between the main switch and ground.
The mechanical linkage locks the disconnector handle. It cannot be pulled open until the main circuit breaker confirms a successful trip.
Once the breaker is open, the operator manually rotates the disconnector blades, creating a safe, highly visible isolation gap.
Only after the main disconnector is fully open can the earthing switch be closed to ground the circuit. This final action unlocks the switchgear cabinet door for safe maintenance.
| Parameter | Unit | 12kV Indoor Series | 24kV Indoor Series | 36kV Indoor Series |
|---|---|---|---|---|
| Rated Voltage | kV | 12 | 24 | 40.5 |
| Rated Current (Max) | A | 400 / 630 / 1250 / 3150 | 630 / 1250 | 630 / 1250 / 2000 |
| Rated Short-Time Withstand Current (3s) | kA | 20 / 31.5 / 40 | 20 / 31.5 | 25 / 31.5 |
| Rated Peak Withstand Current | kA | 50 / 80 / 100 | 50 / 80 | 63 / 80 |
| Phase-to-Phase Distance | mm | 150 / 210 / 250 | 210 / 275 | 300 / 400 |
| Integrated Earthing Switch | - | Optional (Mounted on Load side or Busbar side) | ||
| Operating Mechanism | - | Manual CS6 Type / CS11 Type / Motorized Drive Available | ||
Linear (GN19) isolators have blades that open vertically or horizontally like a knife, requiring more vertical/horizontal clearance inside the cabinet. Rotary (GN30) isolators feature blades that rotate on a central post. This rotary action significantly reduces the physical depth and height required, making it the preferred choice for modern, ultra-compact switchgear.
Yes. Because switchgear layouts vary, the operating shaft can be customized to extend from either the left or right side of the disconnector frame, allowing panel builders to mount the CS operating mechanism handle exactly where it aligns with the cabinet door slot.
Yes. Certain models feature resin cast base plates that act as wall bushings. This allows the disconnector to be mounted through a metal partition within the switchgear, physically separating the busbar compartment from the cable compartment while providing isolation.
Submit your requirements on a business day, and our engineers will provide an initial OEM proposal within 24 hours.
We supply complete medium & high voltage solutions, including:
• Air Insulation Series
• Gas Insulation Series
• Switching Devices
• Instrument Transformers
