scope:

This standard applies to LU and LU Suppliers for new 22kV/433V and 11kV/433V, 50 Hz, three phase auxiliary transformers, associated equipment and documentation, to be installed on LU Power Network. The equipment shall provide protection against electric shock in accordance with BS EN 61140.

Purpose

This standard states the technical requirements for the design, manufacture and testing of 22kV/433V and 11kV/433V, 50 Hz, 3 phase auxiliary transformers, associated equipment and documentation for use on the London Underground (LU) Power Network to provide power for signalling, substation, station and depot services, and other authorised uses.

The transformers are used, typically, to provide supplies to signalling equipment, substation, station and depot services including drive systems for pumps, lifts and ventilation plant.