What is a Medium Voltage (MV) Switchgear? Metal-Clad and RMU Switchgear.
Medium voltage (MV) switchgear is a metal-enclosed switching equipment that provides distribution, switching, and protection of electrical energy, typically between 1 kV and 36 kV. It plays a critical role at the entry points of power distribution networks and large facilities.
Types of Medium Voltage Switches
- Metal-Clad Enclosures: These enclosures offer the highest level of security, with circuit breakers, busbars, and cable compartments separated by metal partitions. Their pull-out circuit breaker design facilitates easy maintenance.
- Gas insulated modular switchgear (RMUs): These are compact, typically SF6 or solid insulated cubicles used for supplying power to individual rings in distribution networks.
Insulation Technologies
Medium voltage (MV) switchgear offers both air-insulated (AIS) and gas-insulated (GIS) solutions. GIS switchgear occupies less space and is more resistant to environmental conditions; AIS switchgear, on the other hand, can provide advantages in terms of maintenance and cost.
Relevant Standard: IEC 62271
Medium voltage switchgear is designed according to the IEC 62271-200 standard and its internal arc classification (IAC) is tested. This is a critical performance indicator for personnel safety.
Devpan’s medium-voltage switchgear , with metal-clad and RMU options, offers reliable solutions for energy distribution projects.
Frequently Asked Questions
In what voltage range does a medium-voltage switch operate?
Medium voltage switchgear is generally used for the distribution of electrical energy between 1 kV and 36 kV.
What is the difference between metal-clad and RMU cubicles?
Metal-clad enclosures have compartments separated by metal partitions and contain a withdrawable circuit breaker; an RMU, on the other hand, is a compact, gas or solid-insulated enclosure typically used for ring network supply.
What is internal arc resistance (IAC)?
Internal arc resistance is a safety classification tested under IEC 62271-200 that indicates the level of protection for personnel in the event of an arc fault occurring inside the enclosure.
