China Outdoor High Voltage Vacuum Circuit Breaker Manufacturer, Supplier, Factory

Kexun Electric Co., Ltd. builds the Outdoor High Voltage Vacuum Circuit Breaker as a sheet-metal enclosure with bushings on top of the box, an operating mechanism inside and a mounting frame underneath, all delivered as one rigid assembly. The box is miniaturised stainless steel rather than painted carbon sheet, which is what keeps the unit clean on coastal and industrial sites. At 600 kg for the complete three-phase body, it is light enough to set on a pre-welded steel structure with a small crane, yet stiff enough to withstand wind speed up to 34 m/s. As a factory with in-house laser cutting, CNC machining, robotic welding and stamping, Kexun controls the enclosure geometry from the first cut to the last weld.

Box, Bushings and Frame

The stainless steel box encloses the integrated magnetic pole assembly, the optional current transformer and the operating mechanism. Three outgoing bushings pass through the top of the enclosure, and the unit is set on the customer's steel structure. Because the box and the mounting points are cut, formed and welded in the same shop, the dimensions stay consistent without on-site adjustment. This Outdoor High Voltage Vacuum Circuit Breaker leaves the factory with the installation drawing, so the civil crew can prepare the steelwork in parallel with the order.

What the Frame Carries

Setting on a Steel Structure

The 600 kg unit is erected on a steel structure, and the installation drawing shows the mounting arrangement. A small crane or a pole-mounted winch handles the lift, and the crew levels the frame before fixing it. Wind load up to 34 m/s is taken by the structure, so the steelwork must be designed for the full face area of the unit.

Erection Sequence

The drawing arrives with the shipment, the steel structure goes up in parallel with the factory build, and the unit is lifted only when the structure is accepted. Once the bolts are torqued, the crew checks that the phase-to-phase distance of 700±2 mm is still true, because a twisted frame is the most common cause of timing problems on a new installation.

Cable and Control Wiring

Power cables land on the line terminals behind the bushings, and the control cable enters the enclosure. The secondary wiring is kept inside the same protected volume as the mechanism, with closing, tripping, motor charging and auxiliary circuits kept apart. Control voltage is AC/DC 220 V, and the secondary circuit passes a 2 kV one-minute power-frequency test, which is the figure that matters when the control cable runs alongside the power cable.

The published ratings behind these clearances and the wiring are listed below; the distances in this section are set by the rated insulation values.

Clearances Around the Unit

Phase-to-phase distance on the pole line is 700±2 mm, and the working clearances around the energised bushings must match the 40.5 kV insulation level, with 90 kV dry and 80 kV wet power-frequency withstand between phases and to earth, and 95 kV across the open break. The installation drawing marks the minimum approach distance for maintenance personnel, and a fence or a walkway must respect that line. Keeping the bushing line clear also matters for the 185 kV lightning impulse level, which assumes the gaps are not bridged by ladders or tools. This Outdoor High Voltage Vacuum Circuit Breaker is supplied with the drawing that fixes those distances.

The mechanical settings the crew checks after erection are listed below.

Sealing and Corrosion Details

The box is stainless steel, so the unit handles pollution grade IV and ambient from −30 to 60 °C without an extra hood. Storage before erection is covered from −40 to 85 °C, which means a unit left on site over a cold winter does not need a separate drying cycle. The laser-cut sheet and robot-welded seams are what keep the enclosure sound across 10,000 mechanical operations, on a site where external vibration or ground motion is disregarded in the design. This Outdoor High Voltage Vacuum Circuit Breaker is therefore a long-life enclosure rather than a painted cabinet that needs repainting.

Shop Control Over the Box

Laser cutting sets the blank sizes, CNC machining fixes the hole positions, robotic welding runs the long seams, and stamping forms the panels. Because all four steps happen in the Yueqing plant, the box and the mounting points come off the same drawing and stay consistent across batches.

Frequently Asked Questions

Q: How heavy is the unit and what lift is needed?

A: The complete three-phase body weighs 600 kg, so a small crane or a pole-mounted winch is enough for the lift. The installation drawing shows the mounting arrangement, and the crew levels the frame before fixing it.

Q: What does the installation drawing fix?

A: The drawing fixes the mounting arrangement, the phase-to-phase distance of 700±2 mm and the space needed around the bushings. It is sent with the shipment so the civil crew can prepare the steelwork in parallel with the factory build.

Q: How is the control cable brought into the box?

A: The control cable enters the enclosure and lands on the secondary terminals, with closing, tripping, motor charging and auxiliary circuits kept apart. Control voltage is AC/DC 220 V, and the secondary circuit passes a 2 kV one-minute power-frequency test.

Q: What clearances must be kept around the bushings?

A: The insulation level is 40.5 kV, with 90 kV dry and 80 kV wet power-frequency withstand between phases and to earth, 95 kV across the open break, and 185 kV lightning impulse peak. The installation drawing marks the minimum approach distance, and a fence or walkway must respect that line.

Q: Is the stainless steel box suitable for coastal sites?

A: Yes. The enclosure is stainless steel rather than painted carbon sheet, and the unit is rated for pollution grade IV and ambient from −30 to 60 °C. Storage before erection is covered from −40 to 85 °C.

Q: What wind load is the frame designed for?

A: The unit itself is rated for wind speed up to 34 m/s, but the wind load is taken by the customer's steel structure. The structure must be designed for the full face area of the unit, and the drawing fixes the mounting arrangement the steelwork must match.

Q: Can you supply the steel structure as well?

A: The steel structure is normally supplied by the customer's civil contractor to the installation drawing. Kexun supplies the breaker, the drawing and the test record, and the export sales managers discuss the interface with the civil engineer in English.

Q: What is the minimum order and payment terms?

A: The minimum order is one set. Standard models are held in stock, which keeps the delivery period short, and payment is by T/T or L/C. Custom work to customer drawings or samples is accepted, with a detailed discussion before production and a start only after the buyer confirms the drawing.