DC Enabling Works
Core Node is a principal site in the FTN/GSM-R Network where essential equipment requiring DC distribution has to be backed up with a dual feed arrangement. A previous investigation by Network Rail had determined that the cabling between the DC UPS and the DC distribution boards feeding the essential equipment did not have autonomous A + B feeds.
Network Rail appointed ADUK to provide a solution for the provision of a dual feed from the existing DC PSU to the Power distribution racks that gave full autonomy to the A + B feeds to the essential equipment. This included the replacement of faulty battery back up systems.
Description of Works Carried Out
The initial solution suggested by NR was to re arrange the existing equipment into 2 autonomous systems and then re arrange the cabling to each of the PDU cabinets. After an initial survey and investigation by ADUK it was found that the original equipment provided was old generation and no longer in production with the supplier and sourcing of key components to upgrade the expansion cabinet to a Master cabinet was not possible.
The solution offered by ADUK was to replace the old system with 2 new Eltek Flatpack2 DC UPS systems each dimensioned at 54Kw of rectification with a growth capacity to 72Kw per system. All work had to be carried out under live conditions with all connections being tested and made live before commencing with the relocation of the partner feed.
A procedure was developed by ADUK that maintained the integrity of the equipment during the “live cut over” which was carried out under ”At Risk” notification taking suitable precautions that ensured that no interruption or interference was caused to safety critical essential circuits.
The activity commenced with delivery of the equipment to site and the preparation of the work area and was completed when the B feed PSU and associated cabling where switched live 10 working days later.
ADUK undertook the Procurement of the following materials:
- DC UPS system and Batteries
- 300mm2 LS0H cable
- 150mm2 LS0H cable
And provided the following service and deliverables:
- Installation and Commissioning of the DC UPS systems and batteries
- Live cable re arrangement to give full autonomy on A + B feeds
- Live switch over of the new DC UPS system without loss of essential service
- AS Built documentation
- Operation and Maintenance/Health and Safety File
- Work Package Plans
- Site specific Task Briefing sheets & SOPP packs
- Progress reports to client