Simulated mains failure to test correct functionality of standby power systems - Woking Data Hall, Kestrel Way, Goldsworth Park Trading Estate, Woking, London High voltage incoming supply B to be switched to 'Off' at DNO sub-station to simulate loss of mains . High voltage incoming supply A will not be affected by these works. • Supply 'B' to be switched to 'Off', correct functionality of power stream 'B' standby power systems to be confirmed this will also encompass DNO HV sub-station remote switching confirmation • Systems are to be monitored, checking correct functionality. Following reinstatement of HV supply 'B', all systems checked and monitored • Digital Realty has made every effort to minimise disruption to customers, however this is a mandatory exercise required by UK Power Networks