RMSYS switchboard (Ring Main Unit - RMU) is composed by a stainless steel tank containing all the switching device and live parts: three position on-load switches (closed, open and earthed), vacuum circuit breaker or fuses for the protection of the transformer and/or outgoing lines. A relief valve ensures the safety in the event of overpressure inside the container, in accordance with the standards IEC 62271-1. A manometer placed on the front constantly monitors the internal pressure. The switchboard is completed with a supporting metal structure divided into separate operating units.
|Rated power-frequency withstand voltage 50Hz 1min||kV (r.m.s.)||28 (42)*||50 (75*)|
|Rated lightning impulse withstand voltage||kV (peak)||75 (95)*||125 (150)*|
|Rated current main bus bars up to||A||630|
|Rated current functional units||A||630|
|Short-time withstand current||kA||20 - 3s|
|Withstand internal arc||kA||20 - 1s|
|Protection degree stainless steel tank||IP||67|