Whilst enroute, the crew experienced a number of cautions and warnings on the Central warning Panel (CWP). The number of these increased, and cabin and cockpit lights also started to fail. The aircraft diverted to Manchester, where an uneventful landing was made. It is suspected that there had been a failure of the right starter/generator or its Generator Control Unit (GCU) and that a further latent failure of a contactor had prevented automatic connection of the right DC bus to the left DC bus. The services normally powered by the right DC bus would now be powered by the main aircraft battery, which would progressively discharge.