Vacuum circuit breakers and load-break switches are matched to the host switchgear, operating duty, interlocking scheme and protection requirements. Exact mounting dimensions, mechanism, auxiliary contacts and ratings require drawing confirmation.
Available product families



Technical information required
| Electrical system | Rated voltage, frequency, neutral/earthing method and applicable standard |
|---|---|
| Continuous duty | Busbar and feeder current, load type, diversity and future expansion |
| Fault duty | Prospective short-circuit current and required duration |
| Protection & control | Relay functions, CT/VT data, metering, communication and remote operation |
| Mechanical interface | Single-line diagram, panel lineup, cable size/entry, room dimensions and access |
| Service conditions | Indoor/outdoor, altitude, ambient temperature, humidity, pollution and seismic duty |
Engineering and quality control
Each quotation is based on a technical review. Final electrical ratings, components, dimensions, interlocks, accessories and documentation are stated in the approved technical agreement and drawings. Images on this page illustrate relevant product families and must not be used as final construction drawings.
Product Selection Guide
| Switchgear switching and protection | QCDL indoor vacuum circuit breaker, selected by voltage, current, fault level, installation type and switchgear interface. |
|---|---|
| RMU incoming or outgoing feeder | FLN36 load-break switch with manual or motorized mechanism. |
| Transformer feeder protection | FLN36 switch-fuse combination, with fuse selection coordinated to transformer rating and protection requirements. |
| Outdoor feeder protection | Outdoor vacuum circuit breaker selected by network duty, control and environmental conditions. |
Engineering Deliverables
Mounting, pole pitch, contact arm, chassis, control voltage and secondary plug are checked against the host switchgear.
Datasheet, outline drawing, wiring information, accessory schedule and agreed inspection records.
SLD review, model selection, technical clarification, OEM coordination, FAT and export packing support.
Frequently Asked Questions
How do I select between a VCB and load-break switch?
A VCB is normally selected where fault-current interruption and protection duties are required. A load-break switch is used for load switching and isolation; transformer feeders may use a coordinated switch-fuse combination.
What information is needed to match a replacement breaker?
Provide nameplate data, voltage, current, breaking current, control voltage, installation type, pole pitch, contact dimensions, mechanism and clear photos or drawings of the existing interface.
Can the operating mechanism be motorized?
Motorized operation and auxiliary contacts can be evaluated according to the control philosophy and approved interface.
Can Qiangchi support OEM, panel-builder and EPC requirements?
Yes. Project-specific interface coordination, drawings, technical submittals, branding and inspection requirements can be discussed for the confirmed scope.
Send your project data
Attach the single-line diagram and specification for a configuration review and quotation.