scope:

The contents give detailed guidance on all aspects of testing telecommunications systems where there is a risk of introducing a safety related failure whilst performing maintenance, faulting and renewals. The test plans included in this Code of Practice shall be used unless an equivalent or better alternative has been approved by a competent engineer nominated by Railtrack.

Maintenance Testing shall be used to test equipment replaced into a previously working and commissioned system during maintenance, renewals and faulting. The replacement shall be like for like and any new item shall be operationally equivalent to the original item which it replaces. The design of the system shall remain unchanged.

The scope includes all equipment and systems provided solely for operational purposes and any equipment or systems which are indirectly used for safety related purposes. This includes all network bearer services utilising Railtrack owned infrastructure, including Grant of Use services carried over Finance Lease assets.

The replacement of consumables such as lamps, dry cells, and fuses along with items such as extension bells, keyboards and other simple tasks such as the re-termination of one end of a jumper wire (without reallocation or replacement ) shall not normally require a test plan. The disconnection and reconnection of cables and wires associated with such items must take place in a controlled manner. Checks should be made for cable insulation and general damage when carrying out this work.

A Maintenance Test Plan shall not be required for adjustment activities where electrical circuits are designed to be adjusted eg. transformer tappings, potentiometers, patching panels, uniselectors and Post Office relays.

Care shall, however, be taken to ensure that adjustment straps are correctly terminated, all screw and nuts are tightened and no stray connections are possible.

PURPOSE

This Code of Practice sets out the requirements for compliance with Railtrack Specification RT/E/S/31001 which mandates the maintenance testing arrangements for operational telecommunications equipment following repair or replacement.