RLK disconnectors for 10 kV are intended for making and breaking de-energized sections of an electrical circuit under voltage, for earthing the disconnected sections by means of earthing switches (when fitted and interlocked as part of the disconnector), as well as for switching transformer magnetizing (no-load) currents and the charging currents of overhead and cable lines. The disconnectors are used in 6–10 kV distribution networks, in outdoor switchgear (AIS) of substations, on OHL approaches to substations and distribution points, at OHL sectioning nodes, on tapping structures and portals. Using RLK provides a clearly visible isolating gap and safe operational separation of network sections for maintenance and operational switching.

Disconnectors are manufactured for outdoor service in installation category 1 with environmental classification aligned to EN/IEC 60721-3-4 (stationary use at non-weather-protected locations). The following service conditions apply:
- altitude above sea level not exceeding 1000 m;
- upper ambient air temperature +40 °C;
- lower ambient air temperature -60 °C;
- wind speed up to 40 m/s without icing and up to 15 m/s with icing up to 20 mm;
The surrounding atmosphere is non-explosive; the content of corrosive agents corresponds to atmosphere category II as per GOST 15150-69. In terms of resistance to mechanical influences the disconnectors comply with mechanical execution group (M13+DT13) according to GOST 17516.1-90.

The RLK disconnector is a three-pole rocking-type apparatus. Each pole has two fixed columns mounted on the frame and one moving column on a pivot bracket; the moving column performs a rocking motion along the longitudinal axis of the disconnector, ensuring reliable make/break of the main circuit and forming a visible isolating gap. The design targets long-term service in severe climates, including wind and icing loads, with minimal maintenance.

Technical data

Application and use

RLK-10 is used for:

• operational sectioning of 6–10 kV overhead lines (OHL), creating temporary jumpers and bypasses;
• isolating network sections from the power source without load current, with a visible isolating gap ensured;
• earthing disconnected feeders by built-in or add-on earthing switches for safe work procedures;
• interrupting no-load currents of small/medium-power transformers and charging currents of distribution cable lines and OHL;
• arranging test and measurement points, including applying test voltage to a locally isolated network section;
• providing back-up paths and rapid supply transfer for consumers under contingency and post-fault switching in municipal and industrial distribution networks.

Typical installation sites include substation outdoor switchyards (AIS), distribution points (DP), OHL branching nodes, package substations at industrial facilities, open-pit and haul networks, oil & gas and mining & metallurgical sites, as well as rural distribution networks. The RLK design is convenient for mounting on portals, reinforced-concrete or steel poles, in-span or at anchor locations, allowing “line–line”, “line–bus” and “bus–bus” layouts.

Service conditions

Designed for long-term outdoor operation under ambient impacts including temperature swings, wind loads, icing and insulator pollution. Support (or post) insulators are selected by pollution class (typically Class IV for dusty, industrial and coastal areas) to minimize leakage currents and flashover probability. Use of corrosion-resistant materials (galvanized steel, stainless steel for shafts/fasteners, current-carrying parts of electrolytic copper/aluminium with plated or silvered surfaces) ensures atmospheric corrosion resistance and stable contact resistance. Bearing assemblies and supports of moving columns are rated for lifetime operation without relubrication, subject to scheduled seasonal inspections. The kinematics allow operation with snow/frost accretion; in icing beyond the specified thickness, operations are carried out after mechanical cleaning of the contact zone and hangers according to the operating manual.

With respect to vibration and dynamic effects, RLK withstands repeated operations, short gust loads and electrodynamic forces from short-circuit currents in accordance with the nameplate thermal and dynamic withstand values. Permissible installation tolerances for alignment, mounting height and skew are compensated by the design of the hinged joints and adjustable drive links on site.

Layout and design features

Baseline configuration includes:

• Reinforced frame with anti-corrosion coating, designed for wind, icing and installation/operating loads. The frame allows left/right drive mounting, mirrored link arrangement and rotation of the pole assembly within installation tolerances.
• Two fixed columns per pole carrying fixed contact beams and terminals for cable/busbar connection. Flat or channel-type pads can be supplied for flexible connectors, lugs and bus links.
• One rocking (moving) column with a pivot on a support bracket; kinematics ensure pole synchronization via a longitudinal linkage and an equalizing shaft. Bearing friction is reduced by wear-resistant polymer bushings.
• Multilam (finger) contact system with spring pressure and automatic wear compensation. Silver-plated or tinned contact surfaces lower transition resistance and enhance corrosion resistance. Counter-contact geometry provides “self-drawing” of the blade and a stable closed position.
• Earthing switches (option), single-ended or double-ended, mechanically and electrically interlocked with the main blade, with independent latching in “ON/OFF”.
• Operating mechanism - manual three-position (closed/open/earthed) or motorized with remote control, limit switches and SCADA integration (dry contacts for position signalling, reed switches, angle sensors).
• Insulators porcelain or polymer with silicone sheds, selected by pollution class, withstand level and mechanical strength; polymer insulation offers hydrophobicity and UV resistance.
• Terminals for aluminium/copper conductors and busbars (bolted clamps, cable lugs, bus joints), with optional flexible links to accommodate thermal expansion and vibration.

Kinematics are optimized: fewer rocking joints and unified links minimize backlash and ensure repeatable contact pressure across all poles. Moving parts are locked for transport. Drip shields and splash guards in the contact zone reduce the effect of precipitation and dust.

Safety and interlocking

• Mechanical interlocking prevents closing the earthing switch with the main circuit closed and, conversely, closing the main blade with the earthing switch engaged.
• The operating mechanism includes end-position latches and holes for padlocks/tags to support Lockout/Tagout procedures.
• Optional limit switches for “CLOSED”, “OPEN”, “EARTHED” positions for dispatching systems and permissive/blocking schemes.
• The visible isolating gap with open blades provides direct visual confirmation and enhances maintenance safety.
• Declared thermal/electrodynamic withstand values confirm the ability to endure fault current shocks for the specified time without residual deformation affecting future closing performance.

Configurations and options

The RLK-10 family covers 400 A and 630 A ratings; versions without earthing switch, with single-ended (on fixed or moving side) or double-ended earthing switches; manual or motor drive; porcelain or polymer insulation; mounting and linkage orientation variants. Options include contact plating choices, terminal types, flexible links, shunts and measurement taps. A “winter” package with increased drive torque and anti-adhesive coatings is available.

Standards compliance

RLK-10 disconnectors are designed and manufactured in accordance with applicable norms and rules. Key standards and documents:

• EN/IEC 62271-102 - High-voltage switchgear and controlgear - Part 102: Alternating-current disconnectors and earthing switches.
• EN/IEC 62271-1 - High-voltage switchgear and controlgear - Part 1: Common specifications.
• EN/IEC 60721-3-4 (outdoor, non-weather-protected) and, where applicable, EN/IEC 60721-3-3 (weather-protected) - Classification of environmental conditions.
• EN 50110-1 - Operation of electrical installations (requirements for safe operation and work).
• EN/IEC 61936-1 - Power installations exceeding 1 kV AC - Part 1: AC (substation/site design fundamentals).
• IEEE C37.30.1 - Requirements for AC air switches rated above 1 kV (application reference for disconnect switches, where applicable).
• GOST 17516.1 - General requirements for resistance to mechanical influences (mechanical group M13+DT13).

Benefits of RLK-10

• Reliable visible isolating gap and high contact stability under dynamic loads.
• Simple, rigid mechanics with minimal maintenance; 2000 CO operating cycles.
• Flexible options for layout, drives, insulation and accessories.
• Resistance to pollution and weather impacts in the specified outdoor service class.
• Optional remote control and integration into SCADA/telecontrol systems.

Engagement with contractors, electrical equipment manufacturers and investors

We welcome cooperation with mechanical engineering companies, assembly plants, foundries and machining shops, suppliers of polymer insulation and plating, as well as drive integrators and telecontrol system vendors. We can organize the full cooperation chain: from frame cutting and welding to machining of shafts and links, manufacturing of contacts, assembly, routine testing and serial shipment. For investors, we offer participation in localization of parts and assemblies, including busbar stamping and milling, fabrication of insulating parts, and fastener kits. For electrical OEMs, we will prepare an adaptation package tailored to your manufacturing capabilities, support industrialization and perform quality audits at acceptance stages.

Documentation offered (drawings, 3D models, AutoCAD, SolidWorks, DXF, DWG, Parasolid)

On request we provide a complete set of design and production documentation for serial manufacture of RLK-10 disconnectors at your facility:

• 3D CAD models of units and assemblies in STEP/Parasolid, solid models in SolidWorks, and visualizations for production planning.
• Working drawings DWG/DXF (AutoCAD), BOMs, purchased-parts lists, coating/tolerance charts, adjustment parameter lists.
• Wiring diagrams, kinematic schemes, drive mounting drawings, adjustment charts and jigs for link alignment.
• Technical specifications, operating manual, test program & procedure, passport/forms, shortage lists.
• Layout album (portal, pole, restricted spaces), preservation/transport instructions, maintenance recommendations.

All documentation can be aligned with project requirements, regulatory framework and your manufacturing capabilities (equipment range, CNC/welding, fits & tolerances, plating and painting). We provide author supervision during pilot batch manufacture and validation of the assembly process.

We offer documentation for manufacturing RLK disconnectors:

- Preliminary technical documentation for tenders to manufacture RLK disconnectors. We will prepare the information required to assess manufacturability against tender requirements and data sheets.
- Working drawings, 3D models and other documentation for RLK-10 manufacture at your plant. If you do not plan to produce parts in-house, we can place orders at partner facilities; your plant will perform final assembly and installation.
- All documentation can be adjusted to your project requirements and your plant’s process capabilities.
- If equipment from another manufacturer is installed at the substation, we will prepare documentation for compatible equipment to complement the existing installation.

Why work with us

• No need to maintain a large staff of high-level instrumentation and process engineers: you receive a documentation set that an engineer of average qualification can use under our guidance.
• Our implemented projects allow serial launch without costly prototypes, cutting time-to-market.
• We advise on all aspects of RLK-10 assembly, adjustment and testing, and help you build stocks of materials and spares.
• We flexibly adapt the design for import substitution and local component ranges.

For additional information on RLK disconnectors please contact: inbox@proekt-energo.com

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