Aysan Elektrik

Ring Main Unit FBX

Ring Main Unit (RMU) FBX

Ring main unit for secondary distribution applications

FBX is an indoor, compact sulphur hexafluoride (SF6) insulated ring main unit for secondary distribution
applications with a service voltage up to 24kV / 630A.
FBX range includes a number of compact and modular functional units for secondary distribution needs.

FBX-C Version (compact)
• 2, 3 or 4 functions

FBX-C Version (extensible)
• 1, 2, 3 or 4 functions

Functional units
• C - feeder with switch disconnector
• T1 - feeder with switch disconnector and fuses
• T2 - feeder with vacuum circuit breaker
• R - direct incoming
• Sb - busbar switch disconnector
• RE - busbar riser with Earthing switch
• CB - outgoing feeder with vacuum circuit breaker
• M - metering panel

Main characteristics

Internal arc withstand
• 3 side protection: 20kA/1s, A-FL
In accordance with AS 62271-200
Protection index
• Gas insulated switchgear (GIS)
• Class: PM (metalic partition)
• Tank: IP67
• Switchboard: IP3X (option: IP33)
• Between compartments: IP2X


• Commercial, industrial, mining and public distribution.
• Prefabricated MV/LV substations
• Remote management and monitoring (Easergy T200)

Simple erection and assembly

The extension is a very simple process thanks to:
• The A-link device used to connect the busbars of two cubicles.
Variations in positioning are compensated by fixed, spherical
contacts and mobile coupling that can be adjusted axially and radially.
• Highly secure dielectric seals made with silicone insulating conical
connectors adapted to the electrical voltage. The assembly of the
insulating connectors is maintained by a mechanical force generated
• Integrated guiding pins for the correct alignment of the cubicles
• An assembly by bolts secured by mechanical stops.
During the assembly of an extension cubicle, an additional space of
at least 450 mm is necessary to allow for handling.