The primary difference is voltage class. KYN28-12 is rated for 12kV (10kV systems) while KYN61-40.5 is rated for 40.5kV (35kV systems). They serve different voltage levels in the distribution network: KYN28-12 is the workhorse of secondary distribution — used in 10kV/12kV substations, building MV services, industrial plant distribution, and EV charging stations. KYN61-40.5 handles the higher 35kV/40.5kV level — used in primary substations, large power plants, and the collection side of utility-scale wind and solar farms. Both share similar metal-clad architecture with withdrawable breakers and arc-resistant design, but the 40.5kV version has larger insulation clearances, bigger busbars, and different breaker types (ZN85 vs VD4/VS1). Choose based on your system nominal voltage — 10-12kV → KYN28-12, 35-40.5kV → KYN61-40.5.

KYN28-12 uses a center-mounted (mid-position) breaker truck design where the vacuum circuit breaker is positioned approximately in the middle of the cabinet height. This offers several advantages: balanced weight distribution means the handcar rolls smoothly with minimal effort; the breaker aligns naturally with both the top busbar connections and bottom cable connections; and maintenance access to both primary and secondary connections is ergonomic. Compared to bottom-mounted designs, center-mounting provides better weight balance and easier breaker handling. Compared to top-mounted designs, it keeps the center of gravity lower for stability and provides better cable compartment access below. The center-mount design is one reason KYN28 has become the dominant withdrawable switchgear platform — it strikes the optimal balance between compactness, safety, and maintainability.

Yes, the KYN28-12 platform is compatible with multiple VCB brands. Standard options include VD4 (ABB design), VS1 (Chinese standard), and ZN63 series circuit breakers. The handcar dimensions and primary contact spacing are standardized across these breaker types, so the cabinet itself doesn't need to change. We can supply the switchgear with your preferred breaker brand or recommend the best option based on your application requirements and budget. All breakers use spring operating mechanisms with both manual and motor-charged options. If you have a specific breaker brand in mind, just let us know and we'll verify compatibility and provide a custom quote. We also offer GOHO-branded VCBs that are fully interchangeable with major brands at a more competitive price point.

The low-voltage compartment accommodates a wide range of protection relays. Standard offerings include: numerical microprocessor-based multifunction relays from major brands (or our GOHO range); electromechanical relays for basic schemes; and application-specific relay packages for feeder protection, transformer protection, motor protection, generator protection, capacitor bank protection, and more. The relay panel can be custom-configured with meters, indicators, control switches, selector switches, and SCADA communication modules (IEC 61850, Modbus RTU/TCP, DNP3). For EV charging stations, we offer dedicated protection schemes with metering and load management integration. Provide us your protection philosophy or single-line diagram and we'll design and build a complete protection and control package fully tested at the factory.

One of the biggest advantages of withdrawable switchgear is the speed of breaker replacement. With a spare breaker truck on hand, a faulty breaker can be swapped out in 15-30 minutes — compared to several hours or even days for fixed-type switchgear where you'd need to work inside the energized panel. The procedure is: open the breaker and rack it out to the disconnected position (following proper safety and lockout/tagout procedures), release the secondary plug, roll the breaker truck out on its guide rails, roll in the spare breaker, connect the secondary plug, rack it in to the test position for verification, then rack to connected position and close. Because all handcars of the same specification are fully interchangeable, one spare breaker can serve as backup for an entire switchgear lineup — saving both downtime and spare parts cost.

Absolutely — KYN28-12 is the standard MV switchgear choice for large DC fast charging stations with 10+ chargers. In a typical EV charging hub configuration, the KYN28-12 serves as the 10kV/12kV main switchgear, receiving power from the grid and distributing it to multiple charging station transformers. The arc-resistant design (IAC AFLR 40kA) protects maintenance technicians working in the charging station's electrical room. The withdrawable breaker design means if a breaker needs service, you can swap it quickly and get chargers back online fast — critical for revenue-critical charging infrastructure. With the 4000A high-current variant, a single switchgear lineup can support a 10MW+ charging hub. KYN28-12 is also commonly integrated into our EV charging prefabricated substations as the MV section of a complete MV-LV pre-assembled package.