Air-Insulated Ring Main Unit
General Description:
- The Air-insulated Ring Main Unit is a factory built, metal-encapsulated switchgear, prewired and tested, eliminating technical coordination problems and ensuring short delivery time and simple erection.
- Local work is limited to the connection of external power cables.
- The Ring Main Unit is designed for either indoor or outdoor installation.
- The Ring Main Unit is mainly used in secondary distribution.
- It integrates from 1 to 4 load-break switches for cable or transformer, an earth fault indicator and an arc extinguishing device.
- The Ring Main Unit also has the option for installing Metering devices.
Main Features:
– High operating reliability
– Simple maintenance and inspection
– No isolating partitions
– High dynamic and thermal strength
– Encapsulated extinguishing device
– Current interruption without visible arc
– High number of operation, simple mechanism
– Easy cable connection
– Possible to be connected with any SCADA system
Approval:
12 & 24 KV Ring Main Units passed all necessary tests carried out in The Egyptian Electricity
Authority Pyramids High Voltage Research Center and approved from The Egyptian Electricity
Holding Company.
Standards:
The Ring Main Unit is designed, manufactured and tested in conformity to the latest standards
– IEC 60271-200
– IEC 60694
– IEC 60271-102
– IEC 62271-105
– DIN VDE 0670
Compact Design
Modular Design
| TECHNICAL DATA | |||
|---|---|---|---|
| Rated Voltage | 12 KV | 17.5 KV | 24 KV |
| Rated Frequency | 50/60 HZ | 50/60 HZ | 50/60 HZ |
| Rated Current | |||
| Ring Switch | 630 A | 630 A | 630 A |
| Transformer Switch | 630 A | 630 A | 630 A |
| Busbars | 630 A | 630 A | 630 A |
| Power Frequency Test Voltage | 28 KV | 38 KV | 50 KV |
| Impulse Withstand Test Voltage | 75 KV | 95 KV | 125 KV |