High-voltage ring main units (HV RMUs) are compact and expandable metal-enclosed switchgear that use sulfur hexafluoride (SF₆) load switches as main switches, adopt air insulation for the entire cabinet, support power distribution automation, and are also suitable for box-type substations. HV RMUs feature a simple structure, flexible operation, and reliable interlocking. They can provide satisfactory technical solutions for various application scenarioses and different user requirements. The adoption of sensing technology and the latest protective relays, combined with advanced technical performance and lightweight, flexible assembly solutions, can fully meet the ever-changing market demands.
Main Uses and Scope of Application of High-Voltage Ring Main Units
HV RMUs are suitable for indoor power distribution equipment with three-phase AC 50Hz and a rated voltage of 12(24)kV. They are widely used in industrial and civil cable ring networks and power supply terminals. They are applied in power systems such as small secondary distribution stations, switching stations, industrial and mining enterprises, urban residential districts, airports, railways, tunnels, and high-rise buildings for receiving and distributing electrical energy.
Structural Features of High-Voltage Ring Main Units
1
、The load switch used is an independent unit, filled with SF₆ gas as the insulation medium inside, featuring long service life, high parameters, no pollution, and low maintenance requirements.
2

、The cabinet shell is made of high-quality steel plates or aluminum-zinc coated steel plates (as per user requirements), with advantages including corrosion resistance, oxidation resistance, a novel and attractive external structure.
3、It adopts spring energy storage operation; three phases can trip automatically. The five-prevention interlock is integrated with the operating mechanism, ensuring safe and reliable linkage.
4
、The switchgear can be easily configured into a ring network power supply unit or other wiring modes, and can be extended infinitely.
5、With SF₆ load switches, it has safe and reliable comprehensive performance, is oil-free and non-toxic, and poses no risk of fire or explosion.
6
、The cabinet has a simple structure, convenient operation, small size, light weight, and an attractive appearance.
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