A Ring Main Unit (RMU) is a compact, sealed switchgear assembly used in medium-voltage power distribution networks. It enables the creation of ring-configured electrical grids — where power can flow in multiple directions — dramatically improving supply reliability and fault tolerance.
If you're planning a distribution network, here's what you need to know about RMUs.
How Does an RMU Work?
In a traditional radial network, a single fault cuts off power to every downstream user. In a ring configuration, power can flow from an alternative direction, so only the faulted section is isolated. The RMU is the device that makes this possible — it houses load break switches, circuit breakers, and fuses in a compact, SF₆-insulated enclosure.
Where Are RMUs Used?
RMUs are standard equipment in:
Key Specifications to Define Before Purchasing
Parameter | Typical Range |
Rated Voltage | 12kV, 24kV, 40.5kV |
Rated Current | 400A – 1250A |
Short-Circuit Withstand | 16kA – 25kA |
Insulation Medium | SF₆ gas or solid insulation |
Configurations | 2-way, 3-way, 4-way, or custom |
Pro tip: Define your voltage level, fault current requirements, and bay configuration before reaching out to suppliers. It saves everyone time.
SF₆ or Solid Insulation?
SF₆-insulated RMUs are compact, reliable, and cost-effective — the most widely used type globally. However, SF₆ is a potent greenhouse gas, and some regions are transitioning to solid-insulated (dry-type) RMUs for environmental compliance. Tuoxin Electric supplies both options.
What to Look for in an RMU Supplier
Tuoxin Electric RMU Solutions
We manufacture SF₆-insulated and solid-insulated RMUs rated 12kV-40.5kV, with customizable bay configurations. ISO 9001 certified, CCC approved, and backed by 16+ years of manufacturing experience.
sale@tuoxinelectric.com | WhatsApp: +86 158 6188 2821
