There is a large brick built relay room for the signalling interlocking equipment together with a local power supply and a backup generator at the Exeter end of the station. This has an emergency operations panel within so an operator can be dispatched from Exeter to help manage local operations in the event of a control link failure. There is a similar smaller facility at Totnes, built at the same time in the mid 1980s. The latter site may have been switched to and left unattended in automatic 'through routes' which in that case would route everything through the platforms automatically. Emergency panels are not fully equipped signalboxes and typically don't have ancillary systems such as train describers, or a switchboard to answer signal telephones or radio systems, so the remote operator has to work in conjunction with the signaller for the appropriate area back at Exeter, being his hands and eyes effectively. The black signals at Dawlish Warren are a result of local power loss, not loss of the control link which would cause all controlled signals to return to their most restrictive aspect. Power may have tripped out during the incident but more likely the lineside 650v cables have been isolated for safety whilst heavy machinery and workers are busy given there is no requirement to run rail traffic except possibly engineering trains within the possession.