NR TI 079 ISSUE 2 PDF

Applies to Permanent Speed Restrictions covered by the ORR exemption and also where the circuitry is basically covered by the TPWS typical circuit "Control Circuits for Retro Fitment of TPWS to Buffer Stops and PSRs" (Drawing T34025). This TI is only to be used where specifically authorised for specific PSRs.

Purpose of TI

An exemption to the TPWS regulations has been granted by ORR. This allows Network Rail to decommission TPWS equipment at selected PSRs. In order to facilitate this work, the TPWS equipment at the selected PSRs will initially be electrically isolated. This Technical Instruction allows that isolation to be undertaken using the Signalling Maintenance Testing Handbook (SMTH).