Summary
Rooq's ring main units (RMU) can be adapted to meet all Medium Voltage power distribution needs,up to 24 kV.
The RM6 is a compact unit combining all MV functional units to enable connection, supply and protection of transformers on an open ring or radial network:
* by a fuse-switch combination, up to 2000 kVA
* by a circuit breaker with protection unit, up to 8000 kVA.
The switchgear and busbars are enclosed in a gas-tight chamber, fi lled with SF6 and sealed for life.
Operating a distribution network sometimes requires switching oints in addition to the HV/MV substations, in order to limit the effect of a fault on the network.
The RM6 offers a choice of solutions to make 2, 3 or 4 directional connections:
* with line protection by 630 A circuit breakers
* with network switching by switch-disconnectors
* with integrated power supply telecontrol devices.
Standard
Rooq's RMU is designed in accordance with the following standards:
General operation conditions for indoor switchgears
IEC 62271-1 (common specifi cations for high voltage switchgear and controlgear)
Ambient temperature: class -25°C indoor
Altitude : lower than or equal to 2000 m
IEC 62271-200 (A.C. metal enclosed switchgear and controlgear for rated voltage above 1 kV and up to and including 52 kV)
Switch-disconnectors
IEC 62271-103 (high voltage switches for rated voltage above 1 kV and less than 52 kV)
Circuit breakers: 200 A feeder or 630 A line protection
IEC 62271-100 (high voltage alternating current circuit breakers)
Other applicable standards
* Switch-fuse combinations: IEC 62271-105:
alternating current switch-fuse combination
* Earthing switch: IEC 62271-102:
alternating current disconnectors and earthing switches
* Electrical relays: IEC 60255.
Features
RM6 switchgear comprises 1 to 4 integrated, low dimension functional units.
This self-contained, totally insulated unit comprises:
* a stainless steel, gas-tight metal enclosure, sealed for life, which groups together the live parts, switch-disconnector, earthing switch, fuse switch or the circuit breaker.
* one to four cable compartments with interfaces for connection to the network or to the transformer
* a low voltage cabinet
* an electrical operating mechanism cabinet
* a fuse chamber compartment for fused switch-disconnectors or fuse switches.
The performance characteristics obtained by the RM6 meet the defi nition of a "sealed pressure system" laid down in the IEC ecommendations.
The switch-disconnector and the earthing switch offer the operator all necessary usage guarantees:
Tightness
The enclosure is filled with SF6 at a 0.2 bar gauge pressure. It is sealed for life after filling. Its tightness, which is systematically checked at the factory, gives the switchgear an expected lifetime of 30 years. No maintenance of live parts is necessary with the RM6 breaking.
Switch-disconnector
Electrical arc extinction is obtained using the SF6 puffer technique.
Circuit breaker
Electrical arc extinction is obtained using the rotating arc technique plus SF6 auto-expansion, allowing breaking of all currents up to the short-circuit current.
.
As per IEC /BSEN 60076 standards these are
set in accordance with the highest voltage for the material,
being the level immediately above the rated voltage.
| Rated voltage |
12kV |
17,5kV |
24kV |
| Frequency |
50 or 60 Hz |
| Insulation level |
|
| Industrial frequency 50Hz 1 min. insulation Ud (kv rms) |
28 |
38 |
50 |
| isolation Ud (kv rms) |
32 |
45 |
60 |
| Impulse 1.2/50us insulation Ud (kv rms) |
75 |
95 |
125 |
| isolation Ud (kv rms) |
85 |
110 |
145 |
| Tank interal arc withstand |
20kA 1s |
Construction details
Global options
* Manometer or pressure switch
* Additional earth busbar in cable compartment
* Internal arc cable box 20 kA 1 s for I, D or B functions.
Option for operation
Voltage indicator
Accessories
* Raising plinth
* Set of 3 MV fuses Fusarc CF
* Phase comparator
* Test box for circuit breaker relay (VAP6)
* Additional operating handle.
Additional instructions:
Installation and civil Engineering instructions.
Connectors and adaptaters for RM6
* Connectors for 630 A (1 set = 1 function)
* Connectors for 400 A (1 set = 1 function)
* Connectors for 250 A (1 set = 1 function).
Protection index
* Tank with HV parts: IP67
* Low voltage control compartment: IP3X
* Front face + mechanism: IP3X
* Cable compartment: IP2X
* Protection against mechanical impact: IK07.
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