A datacentre facility is quite simply a managed and controlled environment in which to run file severs to store, process and deliver information to connected users. A datacentre may be an enterprise facility serving the needs of the organisation or a colocation one that sells space and service to multiple clients. In terms of the management and control of this environment we are concerned with critical power and cooling within the facility. Servers generate heat and the white space needs to be cooled to prevent over-heating and a fire risk. The critical path, from the mains income to the server AC power inputs also requires power protection in order to maintain the service(s).