scope:

This specification defines the electrical and mechanical requirements for a DITA. A DITA may be used in signalling power distribution systems, where the nominal supply voltage is up to and including 650 V a.c. and where the electrical systems are either TN or IT, for power ratings up to and including 20 kVA. The specification also outlines the configurations within which DITAs may be used to create a complete assembly.

For reference, Figure 1 shows a schematic representation of a DITA.

Purpose

This specification defines the requirements for the design, installation, integration and testing of distribution interface transformer assemblies (DITA) into Network Rail managed infrastructure.

The purpose of this specification is to clearly define to manufacturers the performance requirements of a complete DITA and its modules, and to inform power distribution designers who wish to use the design topology of a DITA, and potentially some equipment that already exists, but need to verify that the existing equipment meets the requirements for incorporation into a DITA arrangement.