Raychem Separable Connectors (42kV)

RSTI-6853 Screened Separable Connector (Raychem 42 kV)

The RSTI-6853 is a Raychem screened separable connector from the TE Connectivity RSTI range, used to connect single-core polymeric MV cables to transformer and switchgear bushings on the 42 kV class. Powerpoint Engineering supplies the RSTI-6853 to Irish utilities, electrical contractors, and renewable site installers terminating MV cable into bushing-type C interfaces, where a separable connector is preferred over a fixed termination for maintenance, fault response, and operational flexibility.

Separable connectors are the difference between an outage that needs a jointer and a hot trench, and an outage that just needs the connector unplugged at the bushing. On networks where uptime matters, that is a major operational saving.

What the RSTI-6853 is and what it does

• Screened separable connector: shielded outer surface for safe touch operation when correctly earthed.
• 42 kV class rated: covers 36 / 42 kV system voltage on Irish and continental MV networks.
• 1250 A continuous current rating: suitable for the higher-current MV applications where 630 A separable connectors are not enough.
• Interface C bushing: mates with bushing-type C interfaces specified by IEC EN 50181 on transformers, switchgear, and other MV equipment.
• Single-core polymeric cable: designed for screened single-core XLPE / EPR cable; for three-core cable, the appropriate Raychem three-core terminations are the right product.
• Modular system: works with the wider Raychem RSTI screened separable family, including coupling connectors, T-connectors, and tap-off variants.

Compatibility: cables and systems

Compatibility for separable connectors is a careful match between cable, connector, and bushing. For the RSTI-6853, confirm:

• System voltage class: 36 / 42 kV.
• Current rating: 1250 A continuous; for lower-current installations, the 630 A RSTI variants may be the better fit.
• Cable construction: single-core screened polymeric (XLPE / EPR) MV cable.
• Conductor cross-section: within the connector's stated size range; choose the kit to match the cable being terminated.
• Bushing interface: Interface C per IEC EN 50181 on the equipment side.
• Lug compatibility: confirm the connector body is matched to the lug or compression fitting on the cable.

For three-core polymeric cables that need separable connection, the system uses single-core breakouts plus three RSTI connectors per cable end, one per phase.

Specifications: what to confirm before you order

Target users and applications

• Utilities and DNO contractors connecting MV cable into transformers, switchgear, and ring main units
• Renewable site installers terminating collector cable into wind, solar, and BESS substations
• Industrial electrical contractors carrying out MV cable connection into plant transformers and primary switchgear
• Cable jointing teams replacing legacy fixed terminations with separable connectors for future maintainability

Typical applications include MV cable connection into transformer bushings, primary and secondary switchgear, ring main unit interfaces, and any installation where future disconnection or replacement of the cable is part of the asset management plan.

Powerpoint Engineering supplies the full Raychem RSTI screened separable connector range alongside Klauke crimping tools and lugs and the cable preparation kit needed to install them correctly first time.

FAQs

What is the difference between a separable connector and a heat-shrink termination?

A heat-shrink termination is a permanent cable end that connects to a fixed equipment terminal. A separable connector is a plug-and-socket arrangement that mates to a bushing on the equipment, allowing the cable to be disconnected and reconnected without rebuilding the termination. For maintenance-heavy networks, separable connectors are usually the right choice.

Can the RSTI-6853 be used on three-core cable?

The RSTI-6853 is a single-core connector. For three-core polymeric cable, the standard approach is a three-core breakout plus three RSTI connectors per cable end, one per phase. We can supply the matched breakout kit.

What is Interface C?

Interface C is the standardised MV bushing interface defined in IEC EN 50181, designed to accept screened separable connectors at higher voltage and current ratings. It is used widely on European MV switchgear and transformers above 24 kV.

To match the right RSTI-6853 to your cable, bushing interface, and lug type, request a quote or speak to our team for compatibility advice.