
1. Solution Overview
- Product: KYN28 Indoor Metal-Clad Withdrawable Switchgear
 
- Voltage: 3.6kV, 7.2kV, 12kV, or 24kV (Select based on system voltage)
 
- Application: Power plant distribution, substation receiving/transmission, industrial plant power distribution, large HV motor starting.
 
- Key Advantage: Centralized draw-out design for partial de-energization during maintenance, minimizing downtime.
 
2. Core Technical Specifications
| 
 Parameter 
 | 
 Value 
 | 
| 
 Rated Voltage (kV) 
 | 
 3.6 / 7.2 / 12 / 24 
 | 
| 
 Rated Frequency (Hz) 
 | 
 50 / 60 
 | 
| 
 Rated Current (A) 
 | 
 630 / 1250 / 1600 / 2000 / 2500 / 3150 / 4000 
 | 
| 
 Rated Short-Circuit Breaking Current (kA) 
 | 
 20 / 25 / 31.5 / 40 
 | 
| 
 Rated Short-Time Withstand Current (4s) (kA) 
 | 
 20 / 25 / 31.5 / 40 
 | 
| 
 Power Frequency Withstand (1 min) 
 | 
 Dry: 34-65kV (varies by voltage) Wet: 28-50kV (varies by voltage) 
 | 
| 
 Lightning Impulse Withstand (kV) 
 | 
 75-125kV (varies by voltage) 
 | 
| 
 Protection Class (Housing) 
 | 
 IP4X 
 | 
| 
 Ambient Temperature 
 | 
 -15°C to +40°C 
 | 
| 
 Max. Installation Altitude 
 | 
 1000m 
 | 
| 
 Mechanical Life (Circuit Breaker) 
 | 
 VS1/VD4: 10,000 ops VSM: 100,000 ops 
 | 
3. Key Design Features
- Armored Compartmentalization: Four fully segregated metal compartments (Busbar, Breaker, Cable, Instrumentation) for enhanced safety (IEC 298 / GB 3906-91 compliant).
 
- Centralized Draw-Out: Breaker (e.g., VD4, VS1, 3AH3) mounted on a withdrawable truck. Enables "hot" busbar maintenance without full system shutdown.
 
- Modular & Flexible: Standard widths (800mm/1000mm) allow easy combination of functional units (incomer, feeder, metering, PT).
 
- Special CT Design: Facilitates front-end wall-mounting and maintenance access.
 
- High-Performance Components: Superior insulating materials & conductive elements ensure stability under fault conditions.
 
- Compatibility: Supports major vacuum breakers (VS1, ABB VD4, Siemens 3AH3, GE VB2, ROCKWILL VSM).
 
4. Physical Layout & Dimensions
(Select based on Rated Current & Configuration)
| 
 Cabinet Width (A) 
 | 
 Depth (B) (mm) 
 | 
 Height (mm) 
 | 
 Typical Weight (kg) 
 | 
 Recommended Use Case 
 | 
| 
 650 mm 
 | 
 1400 mm 
 | 
 2200 mm 
 | 
 700 
 | 
 <1250A, Compound Insulation, Front Cable Access 
 | 
| 
 800 mm 
 | 
 1500 mm 
 | 
 2200 mm 
 | 
 800 
 | 
 <1250A, Air Insulation, Front Cable Access 
 | 
| 
 800 mm 
 | 
 1600 mm 
 | 
 2200 mm 
 | 
 900 
 | 
 <1250A, Rear Overhead Line 
 | 
| 
 1000 mm 
 | 
 1500 mm 
 | 
 2200 mm 
 | 
 1100 
 | 
 **>1250A, Front Cable Access** 
 | 
| 
 1000 mm 
 | 
 1600 mm 
 | 
 2200 mm 
 | 
 1200 
 | 
 **>1250A, Rear Overhead Line** 
 | 
| 
 900 mm 
 | 
 1700 mm 
 | 
 2200 mm 
 | 
 1000 
 | 
 Specific config (e.g., with Siemens 3AH5) 
 | 
Note: Height may reduce to 1660mm for 1000mm wide cabinets with rear overhead lines >1600A.
5. Component Selection
- Circuit Breaker Options:
 
- VS1/VD4/3AH3: Standard choice (10k ops).
 
- VSM Magnetic Actuator: Ultra-long life (100k ops) for frequent switching.
 
- Instrumentation: Special CTs for front access, VTs, surge arresters, relay protection devices (overload, short-circuit, earth fault).
 
- Busbars: Main & branch busbars rated equal to circuit current.
 
- Earthing: Integral earthing switch.
 
6. Implementation & Service
- Specification: Define voltage, current, SC rating, breaker type, and layout (front/rear cable access).
 
- Customization: ROCKWILL provides tailored solutions (design, assembly, testing).
 
- Installation: Requires stable environment (<1000m, -15°C to +40°C, <95% humidity). No corrosive gases/vibration.
 
- Commissioning: Functional & safety checks per IEC/GB standards.
 
- Maintenance: Utilize draw-out feature for partial de-energization. Minimal maintenance due to robust design.
 
- After-Sales Support:
 
- Technical guidance via: Tel: +86 (577) 27869969
 
- Email support: support@rockwill.com
 
- Resources: https://www.cnrockwill.com
 
7. Why Choose This Solution?
- Safety: Segregated compartments, front-access CTs, compliance with IEC/GB/DL standards.
 
- Reliability: High-quality components, proven design, comprehensive testing.
 
- Minimal Downtime: Draw-out breaker enables partial maintenance without shutdown.
 
- Flexibility: Modular design simplifies expansion/modification.
 
- Global Support: ROCKWILL’s 20+ years of expertise and direct technical support