Isle of Wight Signalling Insight

Here is an insight into how RSDL have done the signalling on the Isle of Wight addon, that features predominately signal line operation. One thing to bear in mind is that although a computer simulation is a replication of real world operation, it is not necessarily setup in the same manner as the real world.

Although the Isle of Wight Addon features functionality soon to be released in Upgrade Mk2, the signalling system has been designed as stand alone and does not use any of the scripts used on the default routes. This is to demonstrate that although Rail Simulator comes with a signalling system already in the box, it does not need to be the one and only system used for all eternity. You can develop new systems that operate entirely on their own and are custom built per route. Due to the small size and isolation of the Isle of Wight railway network, we decided to script each signal as close to real world functionality as neccessary for the most accurate experience possible.

To facilitate the operation of trains from Smallbrook Junction where the largest portion of single line begins, down to Shanklin at the southern of the line, with Sandown station acting as a passing loop in the middle, there are five signals on the Rail Simulator route. One of these signals does not feature in real life and one signal has been moved to accomodate the connection we have made between the Preserved Line and the Island Line (a connection that does not exist on the real route). On the approach to Sandown from both north and south, there are two point indicators. One directly before the loops at Sandown (PI) and one repeating this indicator (PR). These are only present to tell the driver the state of the junction ahead.

Signals (using the real numbers from the route)

• No. 28 located on the approach to Smallbrook having left Ryde St Johns. This controls trains entering the single line section heading south, and will not allow trains onto the signal line section unless the down platform at Sandown is clear. Effectively token block.
• No. 50 located at the southern end of Sandown on the down platform. This controls trains heading out to Shanklin and will not clear unless the track all the way to Shanklin is clear. Effectively single train working.

• No. 51 located at the northern end of Sandown on the up platform. This controls trains heading north to Ryde, and will not clear unless there is en empty path all the way to beyond the split to double track beyond Smallbrook. This is the opposite of Signal #28.
  • There are signals between this point and on the approach to Ryde St Johns that mean a platform at Ryde St Johns does not need to be clear in order to leave Sandown.
• No. 455 located at the north end of Smallbrook station. This signal has been moved from its real location which WOULD have been to control trains on the approach to Ryde St Johns. This signal in the Rail Simulator route now controls whether it is safe to leave Smallbrook heading north. This is because on the Up line there is the Preserved Line trailing connection, and on the Down line there is a sandtrap trailing connection.

• No. 60 located at the north end of Shanklin for trains heading back to Sandown.This signal will only clear if the Up platform at Sandown is clear.
  • This signal does not exist in real life, but is a requirement in Rail Simulator because we do not handle Token Block or One Train working in the true sense of these functions. Therefore in order to tell the signalling system that a train is now heading back towards Sandown and alert signal 51 to the approach of a train, signal 60 has been installed that tracks trains departing from Shanklin.

Signal Link Functions

• Signal 28
  • 1 = Intermediate link to cope with trains passing into Smallbrook and then heading back north on the Up Line.
  • 2 = Single line exit link. Once the train has passed this link Signal #51 will know the junction at the end of Sandown Loop is clear.
  • 3&4 = If the train passes completely over one of these links, the signal will no longer be concerned about the train unless it is told by another signal that one is coming back.
• Signal 50
  • 1 = Junction clear link. This indicates to the signal that the junction is set correctly for the train to depart south from the Down platform. The signal will remain at danger unless one of two things occurs:
    • The train comes back into the down platform at clears the trigger point of signal 50.
    • The train passes into the Up platform, crossing link 1 while the junction is set against signal 50.
• Signal 60
  • 1 = This indicates that the junction at Sandown is set correctly for the train to enter the Up platform.
  • 2 = If the train passes this link completely it will have entered the domain of signal #50. If this occurs signal 60 will not return to danger unless a train is still sat in the Up Platform, or another train passes south over the junction from the down platform.
• Signal 51
  • 1 = Intermediate link to cope with trains passing beyond it, but not crossing into the single line section, instead reversing into the sidings at Sandown
  • 2 = Intermediate link to cope with trains passing beyond the last junction at Sandown and potentially reversing back into the Down platform. If a train does this, once it has entirely passed over link two into the down platform, Signal 51 will clear again only if all requirements to get beyond Smallbrook are met.
• Signal 455
  • 1&2 = Junction indicator links that confirm if it is safe to traverse from Smallbrook onward to the next signal. Fully crossing link 2 will result in the train passing into the domain of the Ryde St John Starter Signal, and beyond Signal 28 controlling the approach to Smallbrook from the down line.

I hope that helps to explain the setup we have used as well as how you can develop your own scripts, signals, and setups to cover your own routes in Rail Simulator.

RSadam