33kV Three Core Oil to 3 Single Core XLPE Transition Joint: CTM11

The CTM11 joint provides an efficient method of connecting three core oil filled cables to three single core extruded cables.

The CTM11 is recognised as the standard joint within the UK Utilities and rail network industries for 33kV cable repairs or cable re-routing. This enviable position has been achieved due to the joint’s compact size and fast installation time, supported by an exemplary performance and reliability record covering over 500 joints in service since it was qualified nearly 30 years ago. The joint is in demand because it is cost-effective, quick to assemble and requires reduced civil works – this is a significant advantage, particularly in congested cities and sites.

The CTM11 joint is typically specified for 33kV oil cable repairs and diversions allowing a quick assembly of three core oil cable to three XLPE cables. For extra security and protection, the joint is typically placed inside a GRP coffin which is then filled with a re-enterable compound before burial.

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  • Exemplary in-service history
  • Cost-effective
  • Typical 16 hour installation time
  • Most compact joint available requiring reduced civil works
  • Surface-mount or re-enterable direct buried GRP coffin
  • Competitive products have to be installed using their jointer
  • CTM11 installed by independent jointers, saving cost and providing flexibility

Key Features

  • Range taking ability:
    • Three core oil: 34-507 mm², extendable to 630 mm² (assuming concentric cable)
    • Single core XLPE: 95-630 mm²
  • Separable 700 Series Type-E elbows
    • 700 Series elbows can accommodate copper or aluminium conductors
  • Meets ANSI, IEEE 386 specification
  • Also qualified for use with NKT 33kV flat oil cable

The optional direct-buried GRP coffin, which can be supplied with a re-enterable filling compound, offers additional protection, security and flexibility.

The CTM11 transition joint product range is supported by full stock availability at Groove.