Metal-Clad Medium Voltage Switchgear
Fully compartmented, draw-out vacuum circuit breaker (VCB) lineups for medium-voltage power distribution. Arc-resistant type (ARST) options and SCADA integration available from 5 kV to 29 kV.
Draw-Out VCBs with Full Bus Compartmentalization
Metal-clad switchgear is the most robust MV switchgear classification — every functional element (bus, breaker, cables, instruments) is in a separate grounded compartment. Our lineups meet IEC 62271-200 and IEEE C37.20.2 with full three-position (connected/test/disconnected) isolation.
- Voltage range: 5 kV, 15 kV, 27.6 kV, and 29 kV classes
- Vacuum circuit breakers (VCBs) with draw-out chassis
- Grounded barriers between all functional compartments
- Arc-resistant type A, B, or C construction (optional)
- Digital protection relays: 50/51, 27/59, 67, 87T, 87B
- Front and rear cable entry; top or bottom bus options
What's Included
- Withdrawable VCBs with three-position isolation
- Full compartmentalization (bus, breaker, cable, instrument)
- Interlocked safety shutters — breaker cannot close out of position
- Protection relays: 50/51, 27/59, 67N, 87 bus differential
- Front-accessible control panel with local/remote selector
- Voltage indicator lights per NFPA 70E safe work practice
- Grounded metal barriers between all compartments
- Standard steel or stainless steel enclosure options
- +Arc-resistant (ARST) type construction with pressure relief ducts
- +Motor-operated racking mechanism for remote breaker positioning
- +PT cubicle with revenue-grade metering (class 0.2S)
- +Partial discharge monitoring system (on-line PD)
- +Battery-backed DC control power supply
- +SCADA / IEC 61850 communication gateway
- +Witnessed factory acceptance testing (FAT)
- +Arc-flash study and labelling
Full Specifications
| Parameter | Value |
|---|---|
| Voltage Class | 5 kV, 15 kV, 27.6 kV, 29 kV |
| Main Bus Rating | 600 A, 1200 A, 2000 A, 3000 A, 4000 A |
| Interrupting Rating | Up to 40 kA symmetrical (class dependent) |
| Breaker Technology | Vacuum Circuit Breaker (VCB) — draw-out |
| Compartmentalization | Metal-clad: bus, breaker, cable, instrument — grounded barriers |
| Bus Material | Copper, silver-plated contact surfaces |
| Protection Relays | ANSI 50/51, 27/59, 67/67N, 87T, 87B, 81 |
| Communication | Modbus RTU/TCP, IEC 61850, DNP3 (optional) |
| Arc-Resistant Option | ARST type A, B, or C per IEEE C37.20.7 |
| Enclosure | NEMA 1 indoor; outdoor weatherproof housing available |
| Standards | IEC 62271-200, IEEE C37.20.2, CSA C22.2 |
| Lead Time | 8–16 weeks typical; expedited available |
Built to Standard
Where It's Used
- Utility distribution and substation feeder switching
- Mining primary distribution centres (PDC)
- Industrial plant main medium-voltage distribution
- Oil & gas upstream and midstream power systems
- Data centre utility service entrance at 13.8 kV
- Renewable energy generation interconnects
- Transit traction power substations
- University and hospital main campus substations
From design and specification through factory testing, commissioning, and ongoing maintenance — Candron delivers at every phase.
- Engineering drawings and coordination studies
- Factory acceptance testing (FAT) with full reports
- Site commissioning and protection settings
- Spare parts, training, and maintenance support
Common Questions
Metal-clad (IEEE C37.20.2) has individual grounded metal barriers between all functional compartments — bus, breaker, cables, and instruments — with draw-out breakers and interlocked shutters. Metal-enclosed is a broader term covering assemblies where not all compartments are individually separated; load-interrupter switchgear is a common example.
Yes. We offer ARST type A, B, and C construction per IEEE C37.20.7, including pressure relief ducts routed to safe discharge zones. Arc-resistant designs are validated through internal arcing fault testing.
We work with most major relay manufacturers (Schweitzer, GE/Multilin, ABB, Beckwith, Basler). Standard packages include overcurrent (50/51), voltage (27/59), directional (67), and differential (87). IEC 61850 and DNP3 gateways are available.
Ready to Spec
Your Project?
Our engineering team responds with specs, lead times, and pricing the same day. Tell us what you need:
- Nominal voltage and number of feeders
- Main bus and feeder current ratings
- Available fault current (kA) at the bus
- Protection relay functions and SCADA protocol
- Arc-resistant classification required (if any)
- Indoor or outdoor; single-ended or double-ended
Send us your project details and we'll respond with a price, lead time, and any clarifying questions — typically within a few hours.
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