FZW28-12F outdoor Boundary Vacuum Circuit Breaker

1. Product Overview

The FZW28F-12 Outdoor Boundary Vacuum Load Break Switch is designed for pole-mounted applications on 10kV distribution lines. It supports both manual and motorized operations, integrating fault detection, protection, control, and communication in one compact design.
This model incorporates Toshiba’s VSP5-12 maintenance-free vacuum switch technology, using vacuum arc extinction and SF₆ gas insulation for superior reliability and safety.

When installed on distribution feeders, the FZW28F-12 can automatically isolate single-phase grounding faults and cut off phase-to-phase short-circuit faults, improving system automation and reducing power outage areas.
It’s ideal for T-connections, branch lines, and terminal sections in medium-voltage distribution networks that demand fast fault isolation and high supply reliability.

2. Compliance with International Standards

The FZW28F-12 conforms to both IEC and GB international standards, ensuring full compatibility with modern distribution systems:

3. Key Technical Parameters

(1) Switch Body Parameters

Note:

• For altitudes above 1000m, insulation levels must be corrected.

• When an internal PT is used, interphase withstand voltage tests are prohibited.

(2) Controller Technical Specifications

(3) Current Transformer (CT)

• Built-in zero-sequence CT (20/1 ratio), linear range 0.2A–6A, accuracy error <3%.

• Secondary output ≥6A when primary current = 400A.

• Two single-phase CTs (A and C phase) for current protection, ratio 600/1.

• The entire CT is encapsulated in epoxy resin for high mechanical strength and insulation.

(4) Voltage Transformer (PT)

• Ratio: 10,000V / 220V, rated capacity 50VA

• Partial discharge: <10pC

• Provides control power for relays and automation circuits.

4. Structure and Design

The FZW28F-12 consists of two major parts:

• VSP5-12 Vacuum Load Break Switch (Toshiba technology)

• Fault Detection Controller

These are connected via sealed outdoor-grade aviation connectors for secure and moisture-proof performance.

Key Components:

• Arc extinction & insulation: Vacuum interrupter + SF₆ gas chamber ensures long insulation life.

• Operation mechanism: Enhanced electromagnetic actuator enables both manual and motorized control.

• Safety design: Equipped with a pressure relief zone, mechanical “flip-flag” position indicator, and internal CT/PT protection.

• Maintenance-free: Fully enclosed, factory-sealed system minimizes field servicing.

5. Performance Advantages

• Fully Sealed Protection (IP67):
Conforms to IEC 60529, ensuring resistance to dust, water, and corrosion. Operates reliably in coastal, humid, or dusty environments.

• Visible Isolation Point:
Clearly visible break gap ensures safe maintenance and visual confirmation of disconnection.

• Smart Fault Segmentation:
Automatically detects and isolates faults, limiting outage areas and enhancing grid resilience.

• Reliable Vacuum Interruption:
Adopts vacuum arc suppression and SF₆ insulation for fast fault clearing and long service life.

• Low Maintenance Costs:
Maintenance-free design reduces operational expenses by over 60% compared with traditional air-insulated switches.

6. Environmental Conditions

7. Application Scenarios

• 10kV distribution line feeders (T-connections, terminals, and branch circuits)

• Urban and rural grid automation projects for fault isolation

• Industrial zones and commercial complexes require high supply reliability

• Renewable energy systems such as solar and wind power are distributed in networks

8. Quality & Maintenance Assurance

Each FZW28F-12 unit undergoes strict pressure, dielectric, mechanical, and sealing tests before shipment.
Built on Toshiba’s long-proven vacuum switch technology, it offers exceptional reliability and lifespan.

Key Quality Features:

• Vacuum interrupter and SF₆ insulation tested for >30 years of service life.

• 100% factory testing under IEC 62271 protocols.

• Minimal maintenance—visual inspection only required periodically.

Customer Feedback

“After replacing legacy air-insulated switches with FZW28F-12 units, our rural feeders’ fault response time dropped by 70%. Remarkably stable even in monsoon conditions.”
— David Clarkson, Network Engineer, Ausgrid (Australia)

“The motorized operation and remote control integration with SCADA exceeded our expectations.”
— Thomas Reed, Distribution Manager, UK Power Networks

“Reliable, low-maintenance, and fully compliant with IEC standards—perfect for renewable energy substations.”
— Emily Warren, Grid Systems Specialist, Vestas Wind Systems

“Its visible isolation point makes it easier and safer for on-site maintenance crews.”
— Mark Doyle, Operations Supervisor, Pacific Gas & Electric, USA

“We’ve used over 50 sets across our solar substations since 2021—zero SF₆ leakage incidents reported.”
— Patrick O’Connor, EPC Project Lead, Ireland

FAQ – Common Questions

• What voltage level does the FZW28F-12 support?
It’s rated for 12kV systems, suitable for 10kV distribution networks.

• Is it compatible with remote SCADA systems?
Yes. The controller supports RS-485/Modbus and optional wireless modules for integration.

• Can it operate in coastal or high-humidity environments?
Absolutely. The IP67 enclosure ensures long-term reliability even in salt-laden atmospheres.

• What’s the difference between FZW28F-12 and conventional air load switches?
It uses vacuum interruption and SF₆ insulation, which greatly extends lifespan and reduces arc energy loss.

• What maintenance is required?
Only routine external inspections; no internal servicing or gas refilling is needed.

Contact Our Engineer

For detailed technical consultation or system integration advice, contact Thor, Electrical Engineer at Wei Shoe Elec:
📞 Tel: +86-0577-62788197
📱 WhatsApp: +86 159 5777 0984
📧 Email: thor@weishoelec.com