Case Study: Disaster Recovery Server Room Protected for Leading Retail Group

The SRE power projects team were tasked with replacing a legacy UPS system protecting the disaster recovery server room of a leading UK retailer, requiring an out of hours, weekday installation with all works completed before the stores reopened at 9am the next day.

The Power Problem

The server room had several server cabinets housing IT servers that would require an out of hours power down. During this period the existing uninterruptible power supply was to be removed a new modular UPS installed along with additional 32A commando sockets above the server racks to ensure the power distribution units (PDUs) were powered by the UPS. The new UPS system and battery provides N+1 redundancy for the site and is more energy efficient.

Site Challenges

The server room sits on the first floor with access via stairs and a small lift. The lift was large enough for the UPS which was delivered on a pallet along with the batteries. The battery cabinet was dismantled to move into the server room.

The IT systems could not be shutdown till after hours opening of stores across the UK. During the afternoon the UPS and batteries were moved into position, the battery cabinet built-up and DC cables connected. At 18:00 the IT systems were to be shut down, in preparation for the new UPS connection.

The existing UPS maintenance bypass and distribution board were to be used (with uprated breakers) for the new UPS system. The distribution board powered the local area electrical circuits including the air conditioning systems.

The server room floor is solid and there is no raised access floor. This means that all power and network cable routes are top-down, through the ceiling void. As part of the electrical installation, the existing UPS maintenance bypass and Schneider Electric switchboard were reused and additional 32A PDU sockets installed above the server cabinets.

The UPS installation had to be completed during the night and the IT systems brough back online before the stores opened on the next day.

The UPS Solution

A Legrand TRIMOD MCS 40kVA modular uninterruptible power supply was installed to provide 20kVA N+1 resilience and over 30minutes battery runtime. The UPS has a 10year design life lead acid battery in an external battery cabinet. For remote monitoring, the TRIMOD UPS was installed with an SNMP interface card. This give allows the UPS to be given an IP address on the local IT network for browser monitoring and SNMP communications.