NR TI 139 ISSUE 1 PDF

This TI applies to the campaign change programme for MSLs that is being managed by Infrastructure Investment Group and shall not be used for any other changes. The Sites that this and the supporting technical instructions can be applied to have been identified within the campaign change remits / investment papers.

Purpose

This Technical Instruction supports the Process for Campaign Change TI 137 where LED MSL units are fitted in place of the existing incandescent lamp units. This TI allows the change of the MSL to LED by using the campaign change Test Plan contained within this TI. This work will replace the MSL head for an LED type and any changes to the circuitry that are required in the illumination of the LEDs and NOT in the controls. Therefore this work is deemed as non conceptual design. All MSL units at a crossing shall be changed at the same time and mixing of LED and incandescent lamp types is prohibited.

Where changes to batteries are necessary a simple design is required and can be achieved it is authorised as part of the campaign change, so long as the competency criteria has been met.