The KRUN K-59 outdoor switchgear is intended for the reception and distribution of three-phase AC power at 50 Hz with rated voltages of 6 and 10 kV. It is used in auxiliary power switchboards of power plants, at electrical substations of utilities and industrial facilities, for power supply of agricultural sites, as well as in the oil & gas sector.
KRUN K-59 is built from individual modules coupled by demountable joints. Each module is a steel structure consisting of a block of cubicles, a walk-in service aisle, and relay cabinets mounted on a common steel base with fully completed primary and secondary wiring.

Depending on function, cubicles within the module include:
– incoming/feeder cubicle;
– bus section circuit-breaker cubicle;
– bus section disconnector cubicle;
– voltage transformer (VT) cubicle;
– auxiliary services transformer (AST) cubicle;
– combined-equipment cubicle.

KRUN K-59 cubicles are split into mutually isolated compartments, each equipped with its own pressure-relief channel to localize the effects of internal arc faults and protect personnel.

Operational safety is ensured by built-in mechanical and electromechanical interlocks in line with IEC practice and applicable national electrical codes.

Ease of assembly, installation and commissioning is achieved by convenient access to KRUN K-59 cabinet fixing points and to cable and busbar connections.

Secondary circuits are routed in segregated metallic cable ducts providing protection and high electromagnetic immunity.

Extensive unification of KRUN K-59 subassemblies enables adaptation and upgrades in accordance with project documentation requirements.

Technical data

Purpose and application

KRUN K-59 is a modular outdoor air-insulated switchgear (AIS) for medium-voltage networks 6–10 kV. Core functions: power reception and distribution, busbar sectioning and transfer, protection and switching of feeders, supply of power transformers and auxiliary services, measurement and metering, selectivity and fast operation of protections. The equipment is designed for use in open-air switchyards and modular block substations with a 6(10) kV side, as well as at sites requiring rapid deployment and high maintainability. The design supports operation across a wide range of climatic zones, including far-northern areas, coastal regions, and industrial sites with increased dust or humidity.

Typical applications: auxiliary substations of thermal and hydro power plants; distribution points of industrial facilities (metallurgy, chemical, cement); oil & gas production and transport (well pads, pumping stations); mines and processing plants; municipal power (boiler houses, district heating substations, water/wastewater pumping); transport infrastructure (metro, rail, airports); renewable plants at the MV side of wind/PV with interconnection to grid substations. High unification and the use of withdrawable apparatus minimize outage time for maintenance, which is crucial where continuity of supply is critical.

The delivery set and cubicle mix are tailored to the project: incoming and section cubicles with vacuum circuit-breakers; feeder cubicles with cable and overhead connections; VT and AST cubicles; metering, communications, and auxiliary circuits. Integration with SCADA/DCS, AMI/AMR and telemeasure systems is available; standardized ports and interfaces allow modernization without affecting the primary circuits.

Service conditions

KRUN K-59 is intended for outdoor installation at open sites in line with EN/IEC 60721-3-4 (outdoor). Temperature ranges and climatic factors are selected per site: for temperate climates-splash-proof execution with protection against rain and wind-driven precipitation; for cold climates-enhanced thermal insulation, heaters, and higher enclosure ingress protection. The structure is designed for wind, icing and snow loads according to regional maps. Installation is permitted up to 1000 m a.s.l. without derating; at higher altitudes, insulation and thermal ratings are adjusted. The equipment tolerates long-term relative humidity up to 95% without condensation when ventilation and heating regimes are observed, and withstands vibration typical near process equipment.

Ingress protection of the outer enclosure is selected to site conditions: IP34 is sufficient for most regions; IP54 is recommended for dusty, coastal and northern sites. Internally, zoned protection is implemented: partitions and cable routing channels segregate secondary circuits from the MV section and localize potential faults. To prevent condensation, thermostats, heaters and ventilation elements are provided; at sub-zero ambient temperatures, the specified temperature regime is maintained in relay cabinets and compartments with moving drive mechanisms.

Electromagnetic compatibility is addressed at the design stage: cabinets and cable ducts provide shielding, secondary circuits are segregated by function and laid in metallic trays, and separate grounding bars are provided for power and control sections. All conductive parts are bonded to the substation ground grid; provisions are made for portable earthing when performing switching under work permits.

Layout and design solutions

KRUN K-59 is a row of standardized cabinets mounted on a common base frame and enclosed by a single housing with a service aisle. Each cabinet has clearly separated compartments: apparatus (with withdrawable element), busbar, cable, and relay/control. Metal partitions between compartments provide both mechanical and electrical barriers and ensure internal-arc segregation. In the roof area, pressure-relief flaps and ducts direct hot gases upwards and/or away from personnel zones. Doors feature sealing gaskets, concealed hinges and viewing windows (on request).

The withdrawable element with a vacuum circuit-breaker travels on guides and locks in three positions: “service”, “test/isolated”, and “disconnected/maintenance”. Transfer between positions is via a removable handle or built-in racking drive; movement is only possible with interlocks satisfied. Main-circuit contacts use spring-loaded plug-in bus and line interfaces ensuring stable contact pressure and low resistance. For testing, plug-in test connectors and sockets are provided together with test blocks in secondary circuits.

The busbar system uses copper bars sized to the selected continuous current (1250…3150 A) and short-time withstand rating. Joints are bolted with controlled torque; tinned contact surfaces may be applied where needed. The cable compartment supports three-core and single-core shielded cables; cable stools, lugs platforms and brackets are provided, as well as terminations space. Connection options-bottom or top entry; for overhead lines, wall bushings and bus take-offs with guards are used.

The relay/control compartment houses microprocessor-based protection and control IEDs, meters, control panels, I/O modules, and schemes for AR, ATS and fast transfer. Interfaces for DCS/SCADA, telecontrol and AMI include Modbus RTU/TCP, IEC 60870-5-104, and IEC 61850 (incl. GOOSE for high-speed interlocking). Secondary circuits are segregated into power, measurement, DC control and signaling; routes are in metallic ducts avoiding crossings and induced coupling.

Serviceability and ergonomics are emphasized: the aisle provides access to apparatus, instrument transformers, terminal blocks and drives without removing large parts. Maintenance-prone units are positioned for easy reach; windows or removable covers allow thermographic inspection. In cold-climate versions, door and relay-cabinet heaters with thermostats and moisture protection are installed, along with additional cable-gland sealing.

Safety and interlocks

Safety is engineered into both construction and interlocking logic. Key features: interlock preventing movement of the withdrawable element with breaker closed; prohibition of breaker closing in intermediate trolley positions; interlock preventing earthing switch closing with potential present on the feeder; controlled access to the cable compartment (door opening only with earthed feeder and breaker open). Exchange keys and solenoid locks are applied for critical operations. Position indicators, limit switches and duplicate signals in the protection/control circuits are provided.

Internal-arc effects are localized by the enclosure and exhaust flaps: in case of an internal arc fault, hot gases are directed to a safe zone via pressure-relief ducts, protecting personnel in the service aisle. Optional optical/light-sensing arc-flash detection with dedicated high-speed trip logic can be applied for faster clearing. The cabinet and partition layout maintains supply to adjacent feeders during maintenance or failure of one cubicle (LSC2B service-continuity category), important for process loads.

Protection against direct contact with live parts is at least IP2X inside compartments with doors closed. Warning labels, mimic schemes and instructions are placed on doors and guards; provisions exist for portable earthing and for absence-of-voltage checks. All hardware is vibration-resistant; controls are protected against accidental operation and racking mechanisms are force-limited.

Variants and options

• Climatic executions: outdoor per EN/IEC 60721-3-4 for temperate climates; cold-climate version with insulation, heaters and higher IP ratings. Optional enhanced anti-corrosion coating for coastal areas.
• Connection types: cable (bottom/top entry), overhead (through wall bushings), bus take-offs; metering and transformer cubicles; connections to AST and power-line carrier (PLC).
• Switchgear apparatus: 6–10 kV vacuum circuit-breakers on withdrawable trolleys, load break/disconnectors, earthing switches, MOV surge arresters, CTs and VTs per project.
• Protection & communications: feeder/transformer/busbar protection IEDs; automatic reclosing (AR), automatic transfer (ATS), interlocking schemes; integration via Modbus, IEC 60870-5-104, IEC 61850/GOOSE.
• Condition monitoring: busbar/contact temperature sensors, partial-discharge monitoring, breaker operation counters, remote-access modems.
• Mechanics & ergonomics: shutter mechanisms, removable panels, service platforms, snow guards/canopies, condensate drainage, reinforced locks and hinges.
• Environment: low-noise drives, acoustic panels, UV- and chemical-resistant coatings.

Typical configurations

KRUN K-59 supports a wide range of substation layouts. Base configurations:

• Two-incoming section with bus-section circuit-breaker. Input redundancy, automatic transfer, power-quality monitoring and remote control.
• Section with bypass bus. Enables feeder maintenance without process outage, simplifies breaker overhauls and protection testing.
• Industrial section with AST and VT. Includes built-in or stand-alone auxiliary services transformer, metering circuits, automation and communications.
• RES (renewables) MV switchgear. 6–10 kV sections on the MV side of wind/PV plants: cabinets with enhanced measurements, reverse-power protections and interfaces to the grid-substation IEDs.
• Compact distribution point. Several feeder cubicles with a single incoming for local distribution at an industrial site or settlement; lineup can be extended later.

Standards compliance

Design and test regimes for KRUN K-59 follow relevant international standards:

1. IEC 62271-200 - metal-enclosed medium-voltage switchgear: design requirements, Loss of Service Continuity (LSC), partition classes (PM/PI), internal-arc classification (IAC).
2. IEC 62271-1 - common specifications for high-voltage switchgear and controlgear: climatic/mechanical requirements, electrical tests, marking.
3. IEC 62271-102 - disconnectors and earthing switches: drives, interlocks, access control and safety.
4. IEC 61936-1 - power installations exceeding 1 kV AC: substation layout, clearances, evacuation, grounding and lightning protection.
5. IEC 60529 - degrees of protection provided by enclosures (IP Code) for outer and inner enclosures and service areas.
6. EN/IEC 60721-3-4 - environmental classification for stationary use at non-weather-protected locations (outdoor).

Engaging EPCs, manufacturers and investors

We invite EPC/EPCM contractors, electrical installation and commissioning firms, regional manufacturing partners and investors interested in medium-voltage switchgear. We provide a full design package, process sheets, bills of materials, and critical tolerances and QA instructions. Cooperation models include contract assembly to our drawings, supply of semi-finished assemblies (enclosures, trolleys, wall bushings), or localized manufacturing with staff training and joint FAT/SAT.

For engineering companies we offer a library of typical solutions: 3D cabinet models for BIM, templates of single-line diagrams and layout plans, standard specifications, and recommendations for cable routing and service-aisle organization. For investors we prepare TEAs, production ramp-up schedules and localization roadmaps.

Offered documentation (CAD/3D)

We supply and update a complete documentation set for design, manufacturing and operation of KRUN K-59. For CAD/PLM the following formats are available: DWG/DXF (AutoCAD), SLDPRT/SLDASM (SolidWorks), STEP, Parasolid (*.x_t), plus outline drawings, parts lists and questionnaires. The O&M package includes:
- Product datasheet and forms;
- Installation, commissioning and operating manual;
- Main and secondary wiring diagrams;
- Cable specifications and recommended spare parts list;
- Factory and site test programs and procedures.

Recommendations for design, installation and operation

For site design we recommend placing KRUN K-59 on concrete sleepers, leveled and anchored. Plan racking paths for withdrawable trolleys in advance, providing straight access and vertical clearances for apparatus replacement. The service aisle should be continuous, with code-compliant width and lighting. Grounding grid, lightning protection, drainage and segregated cable routes for power and control should be incorporated at the design stage.

Installation stages: receipt of blocks, visual inspection, de-preservation, assembly of sections, checking bolted bus and grounding joints, cable laying and terminations, secondary wiring connection, protection/automation setup, insulation tests and functional checks. Special attention to interlock setting and arc-flash protection verification. Before energization, check trolley racking forces, smooth travel, proper latching in “test” and “service” positions, and conformity of the actual scope to the project documentation.

Operation includes periodic inspections, dust cleaning, torque checks on bolted joints, thermography of live parts under load, and verification of heaters and thermostats in cold seasons. Intervals depend on local conditions; recommended periodicity is at least annually with seasonal checks before winter peak loads. For work-permit tasks, mandatory steps include absence-of-voltage checks, application of portable earthing, restricted access to adjacent compartments, and use of PPE and insulating mats.

Benefits of adopting K-59

• High personnel safety thanks to internal-arc withstand, inter-compartment partitions and a robust interlocking system.
• Maintainability and minimal downtime: withdrawable apparatus, accessible inspection points, advanced diagnostics and monitoring.
• Modularity and scalability: from compact distribution points to sectioned switchyards of large substations.
• Ready for “digital” substations: modern communication protocols and seamless SCADA/AMI integration.
• Climate-ready: EN/IEC 60721-3-4 outdoor execution, IP34/IP54, thermal insulation and heaters, anti-corrosion coatings.
• Lifecycle economy: unified modules, typical solutions, reduced time for commissioning and maintenance.

Why work with us

– No need to maintain a large team of senior engineers - you receive a complete documentation set enabling an engineer of average seniority to manufacture the product.
– No need to build prototypes - our experience allows immediate start of serial production.
– Working to our documentation, your specialists receive consulting on all nuances of KRUN K-59 manufacturing.

For more information on KRUN K-59 please contact: inbox@proekt-energo.com

…and, as is well known, an error made at the design stage results in ten-fold costs in manufacturing and one hundred-fold in operation…

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