• Dutco Tennant LLC, PO Box 233, Dubai, U.A.E.
Insulect Transmission

Insulect manufacture a comprehensive range of fully-tested stainless steel link boxes for high voltage underground cables.

Insulect link box designs use various earthing practices to minimise sheath currents and provide sheath voltage protection.

Direct Earthing or SVL Earthing through sheath voltage limiter surge arrester.

Cross Bonding with insulation withstand between phases.

Cable Sheath Protection using metal oxide sheath voltage surge limiters (SVLs).


The Insulect range of Link Boxes includes two models - Ultra and Lite - and numerous variants to suit all underground cable applications and network requirements.

Our link boxes ensure a weatherproof environment for connecting links, whether for earthing or cross-bonding high voltage cables.

Link Boxes are part of our wider Switchgear product range, which includes switchgear for substations, overhead distribution and underground cable applications.

Available in two models


ULTRA is our original Link Box design, built for demanding conditions and highest performance:

  • Material 316 Stainless Steel
  • Short Circuit 63 kA/1s
  • Enclosure rating IP68
  • Internal power arc 40 kA/0.12s
  • Pressure test meter 10M


The LITE is designed for for less arduous applications and where ease of handling and install is important.

  • Material 304 Stainless Steel
  • Short Circuit 40 kA/1s
  • Enclosure rating IP68
  • Internal power arc 20 kA/0.12s
  • Pressure test meter 2M


COMPREHENSIVE RANGELink boxes of all types for single core and concentric bonding cables

ABOVE OR BELOW GROUND: Universal design to suit indoor, outdoor and in-pit installation UP TO IP68 ENCLOSURES Fully tested and fully sealed stainless steel enclosures, rated at a minimum of IP68 AUSTRALIAN DESIGN AND MANUFACTURE Our link boxes have been designed, manufactured and tested in Australia for over twenty years ALL EARTHING PRACTICES Direct earthing, SVL earthing, cross bonding, cable sheath protection


LINKS Extruded copper in hard drawn high conductivity 300mm2 minimum BODY Stainless Steel 316 or 204 INSULATORS High tension porcelain, stainless steel hardware PLATING All conductors plated with ≥8μm of tin. STRESS CONES Polyurethane elastomer SVLs Zinc oxide sheath voltage limiters