High Breaking Capacity Solid-Sealed Vacuum Load Break Switch 12kV

Overview

• Adopts solid-sealed pole technology
• Modular product with a frame structure, compact in design, integrating disconnectors, vacuum load break switches, fuses, and earthing switches into a high-performance, miniaturized high-voltage electrical appliance
• High breaking capacity type load break switches can directly interrupt 20kA short-circuit current
• Combination units can be matched with 200A fuses
• Rotary disconnector with a visible break after opening
• Load break switches can be optionally equipped with a motor mechanism, supporting both manual and electric operation for remote control
• Incoming line disconnector is interlocked with the earthing switch; when the earthing switch opens, the incoming line disconnector closes in the same operation
• Mechanical interlock between the vacuum load break switch and the disconnector (earthing switch) prevents misoperation, ensuring that the vacuum load break switch can be opened/closed only after the disconnector is closed, and the disconnector can be opened only after the vacuum load break switch is opened
• Optional auxiliary switches, shunt trip, and overcurrent release
• Opening and closing speed of the vacuum load break switch is not affected by the force of manual operation
• Anti-misoperation mechanism meets the "five prevention" requirements for complete high-voltage equipment

Operating Environment Conditions

Normal Operating Conditions:

• Ambient temperature: -25℃ ~ +40℃
• Relative humidity: daily average ≤95%, monthly average ≤90%
• Altitude: not exceeding 1000m
• Seismic intensity: not exceeding 8 degrees
• Application site: free from explosion hazards, chemical corrosion, severe vibration, and pollution

Conditions for Altitudes Above 1000m:

Technical Features

• Excellent Safety Solid-Sealed Poles：High reliability, stable insulation performance, more robust structure, miniaturization, maintenance-free, more environmentally friendly, and high resistance to mechanical stress.
• Visible Isolation Break：Rotary disconnector with a visible break after opening.
• 60° Fuse Holder：More convenient and easier to replace fuses compared to 90° fuse holders.
• Reliable Arc Interruption Performance：Adopts a vacuum interrupter with contacts designed to generate a transverse magnetic field. In the transverse magnetic field contact, when the instantaneous current reaches 10kA, the arc is diffused; at higher currents, a concentrated arc is formed.
• Low Chopping Current：When the current drops below a certain minimum value, the metal vapor arc is interrupted before the normal current zero-crossing, causing overvoltage. Therefore, in inductive circuits, the chopping current should be minimized to prevent high overvoltage. The chopping current mainly depends on the contact material; optimized copper-chromium material can achieve an average chopping current of 3A.
• Low Contact Burning：Due to the excellent conductivity of the metal vapor plasma in the vacuum interrupter, the arc voltage is low (20~200V) during interruption, with low arc energy and short arcing time, resulting in low contact burning and long service life.
• Low Contact Resistance：The contact surface in a vacuum is free from impurities and contamination. Using contact materials with good conductivity ensures minimal contact resistance, resulting in correspondingly lower temperature rise.

Technical parameter

Application

• Urban & industrial power distribution networks
• Ring main units (RMUs) & compact substations
• Distribution transformer protection
• Factories, mines, and railway electrification
• Solar & wind farm grid connection
• Critical infrastructure (hospitals, data centers)