The answer to your SIN119 and power enclosure issues.

A new power annex and bender unit housing has been approved by Network Rail. Henry Williams are proud to unveil their new SafeBox Legacy Connect range of power annex and insulation monitoring housings. This range has been developed in response to NR’s requirement for civils free enclosures to house class II switchgear and equipment; to meet with the requirements of their SIN119 programme.

This versatile box takes into account all of the issues associated with retrofitting enclosures on site, and complements Henry Williams existing FSP and Legacy ranges. It incorporates:



  • Easy and non-intrusive fixing to existing infrastructure and enclosures including location cases.
  • Usable space: the annex has a volume of 0.3m3 and can accommodate any approved transformer up to and including 3KVA.
  • New SafeBox class II switchgear to accept up to 120mm 4 core cable, with oversized termination chambers easing cable preparation in the terminal chamber.
  • Sliding gland plates for ease of fixing terminals.
  • Optional removable sill and sliding base for flexible cable installation.
  • Lightweight aluminium construction for strength and lightness.
    40 year lifespan.
  • No after care in the form of inspections or surveys – maintenance free.
  • No drilling or detrimental work required to the existing case, case remains structurally and environmentally intact.
  • No additional civil work required.

The whole ethos of this enclosure is to make things as quick and easy for the installers as possible. As an engineering company with both design capabilities and state of the art production facilities we are able to manufacture any size or shape of enclosure that is specified.

This durable and versatile enclosure has been given a full and unfettered Product Acceptance. There is no requirement to carry out inspections after installation as there is with GRP or composite alternatives. Fitting this annex does not cause damage to the existing enclosure or compromise the coating. By incorporating Highways grade ventilation our annex is also free of the condensation issues associated with other enclosures. This unit offers an install and walk away solution; simple, high quality: just how it should be.


For more information please see SafeBox Legacy Connect Box.