Next-generation High Capacity Signalling technology is being installed on the Metro Tunnel and on the Cranbourne, Pakenham and Sunbury lines to deliver more trains, more often during peak times.

This is first rollout of High Capacity Signalling on an existing network anywhere in Australia. It will revolutionise Melbourne’s train network as we move towards a reliable ‘turn-up-and-go’ network, similar to those in London, Singapore or Hong Kong.

The bigger, more modern trains running on this new network will provide capacity for 121,000 passengers every week on the Cranbourne and Pakenham lines during peak periods – that’s 45% more peak capacity.

Existing signals used along these lines are also being be updated so trains that use High Capacity Signalling and those that use conventional signalling – such as freight and regional passenger services – can safely and efficiently operate on the one system.

Moving block signalling

High Capacity Signalling is the hi-tech 'moving block' signalling system used around the world that enables trains to automatically adjust their speed to maintain a safe distance from the train in front.

The new technology is more advanced than Melbourne's current 'fixed block' system, which uses coloured signals to indicate when it is safe for a train to proceed.

To visualise how High Capacity Signalling works, imagine driving on a freeway. Adaptive cruise control adjusts the vehicle speed according to the distance from the car ahead, to help the driver travel more safely.

Under the control of train drivers, High Capacity Signalling works in a similar way by communicating this information wirelessly between trains, the railway line and the signal control centres.