The page presents RELF 2S type medium voltage switchgear:
- air insulated,
- double busbar,
- with rated voltage 12 kV,
- for indoor use.
RELF 2S is a modular, withdrawable, metal-clad, air insulated switchgear for primary distribution. It was equipped with double busbar system, which enable the creation of state of the art, complex supplying systems in distribution stations for industry and for generation and distribution sector. The use of interlocks system and an arc-proof design ensures highest possible operational safety and switchgear maintenance. It is intended for operation in normal conditions, as specified by the (PN-EN) IEC 62271-1 standard.
Types of bays
The switchgear may be composed of various functional units:
- feeder bays with a circuit breaker and with optional voltage measurement,
- transverse bus coupler bay,
- longitudinal, double cubicle bus coupler bay with a circuit breaker and sectionalizer,
- metering bay,
- feeder bay with switch disconnector.
The withdrawable module of the switchgear may be equipped with a circuit breaker, contactor, sectionalizer, set of fused voltage transformers. It may be placed in the positions of: service, test/disconnection and separation.
Characteristics and advantages
- visual inspection of the state of switches - disconnectors, circuit breaker and earthing switch
- doors in the rear of the switchgear - excellent access to cables and instrument transformers
- removable inspection plates - easy access to disconnectors
- advanced gas blow-out system - specially designed pressure relief duct discharges pressure from inside the bay
- optional gas exhausting duct - discharges gases outside of the switching room
- remote control - optional electrical drives for all switches
- possibility of equipping with current and voltage sensors
- bay with a fused switch disconnector - auxiliary transformer feeder
- air insulated,
- frame-less, self-supporting design constructed with zinc-coated riveted steel sheets,
- double busbar system,
- IAC AFLR internal arc classification,
- interlocks and protections against performing incorrect switching operations,
- free-standing with access to cable connections from the rear of the cabinet,
- ease of operation,
- versions with manual drives or electrical drives of main switches and withdrawable module are available, depending on requirements and configuration of switchgear bays,
- high operational safety.
The switchgear is designed in a manner that ensures that normal operation, inspections and maintenance operations may be performed in a safe manner.
High operational safety is achieved through:
- internal arc resistance of the switchgear enclosure,
- interlocks between switching operations and opening of doors,
- racking the withdrawable module with doors closed,
- controlling the switches remotely or locally,
- the use of internal compartments and partitions,
- the possibility of visual control of switching operations through inspection windows,
- bay voltage indication system.
Basic technical data
Compliance with standards:
The RELF 2S type switchgear meets the requirements of the following standards:
- (PN-EN) IEC 62271-1 - “High-voltage switchgear and controlgear. Common specifications”,
- (PN-EN) IEC 62271-200 - “High-voltage switchgear and controlgear. AC metal-enclosed switchgear and controlgear for rated voltages above 1 kV and up to and including 52 kV”,
The switchgear is certified by appropriate accredited bodies.
|Basic technical data|
|Main busbars and incoming feeder
rated continuous current
|Rated power-frequency withstand voltage||[kV]||28|
|Rated lightning impulse withstand voltage||[kV]||75|
|Rated short-time withstand current||[kA/3s]||31,5|
|Rated peak withstand current||[kA]||80|
|Withstand for internal arcing fault||[kA/1s]||31,5|
|Degree of protection||up to IP4X|
|Cubicle width||[mm]||650||8001)||800 (650)||800||1100||1100|
|Compliance with standards||(PN-EN) IEC 62271-200; (PN-EN) IEC 62271-1; (PN-EN) IEC 60529|
|1) Width of bay with a switch disconnector
2) Height of the cubicle without the gas exhausting “I” (gas exhausting duct as optional equipment)
The RELF 2S switchgear bay is designed as a cubicle with separate functional compartments:
Functional compartments of a feeder bay with circuit breaker:
- busbar compartment of system I
- busbar compartment of system II
- disconnector compartment of system I
- disconnector compartment of system II
- internal pressure relief and blow-out duct
- auxiliary circuits LV compartment
- main device compartment
- cable compartment
- gas exhausting duct (optional)
Feeder bay with a circuit breaker (option with voltage measurement)
Longitudinal bus coupler bay with circuit breaker
Transverse bus coupler bay
Longitudinal coupler bay with sectionalizer
Metering bay – SYSTEM I and II
Metering bay – SYSTEM II
Metering bay – SYSTEM I
Bay with switch disconnector
|Designations of devices used in the switchgear bays|
Other types of bays on arrangement with the manufacturer.
Bay equipment may be adapted to special requirements on arrangement with the manufacturer.