Hi there. I’m currently in the process of creating some upgrades/enhancements to make the AHS Channel Tunnel route enjoyable. So far I have replaced all the TVM markers for DTG ones and have replaced the majority of SNCF signals too. One of my recent focuses now is correcting inaccurate speed limits there are some areas where the limit is either too low or too high vs the prototypical route/data taken from OpenRailwayMap. I know how to edit speed limits but there is a problem when you are working with high speed lines, by default any speed limit over 200 will show the same “undefined” texture which is not helpful when the majority of your route is above 200. Like you can’t tell the difference between 230, 300 or 320 sections. If anyone else here have route building experience with high speed lines then let me know.
Maybe have a look at what DTG use on the LGV Med - it should be the same being an SNCF route Did you use the TVM markers from the HS1 or a French Route? I noticed although UK trains like the Class 92 and the 395 see the TVM on the LGV-Med the SNCF locos from SimExpress don't.
I used a mixture in order to be prototypical for each operator's standards for TVM. I used markers from LGVMedSouth for the LGV Nord, the tunnel itself and the surrounding area on the UK side. For the rest of HS1 I used the ones from KentHighSpeed. Biggest difference between UK and French TVM markers is the plates that denote if the signal is permissive or not. France uses "F" and "Nf" while UK uses "P" and "N" on their markers, along with a slightly different calling on signal head. I don't own any SimExpress locos but my only guess is that like AHS, they decided to come up with their own TVM system rather than adopting DTG's standards. Edit: Checked LGV Med "Marseille - Avignon" iirc, same default behaviour. I think it is possible as I was poking around in some track rule bin files and there is a line "<TrackSpeedLimitColours/>" but it contains no table or anything else so I don't know how to populate that.
SimExpress adopted the DTG standard that was used on LGV Med - the BB 22200 TVM have that for he Tunnel to Dollands Moor prior to the 92s being introduced https://www.simexpress.fr/produit/locomotives-bb22200-tvm/
Found this in one of my track rules. Not sure if it works in TS since I never use this function. Code: <TrackSpeedLimitColours> <iTrackRulesBlueprint-sTrackSpeedLimitColours d:id="971"> <Colour> <cHcColour> <Red d:type="sFloat32">0.3825726</Red> <Green d:type="sFloat32">0.6</Green> <Blue d:type="sFloat32">0.8</Blue> <Alpha d:type="sFloat32">1</Alpha> </cHcColour> </Colour> <Speed d:type="sInt32">120</Speed> </iTrackRulesBlueprint-sTrackSpeedLimitColours> <iTrackRulesBlueprint-sTrackSpeedLimitColours d:id="978"> <Colour> <cHcColour> <Red d:type="sFloat32">0.8000001</Red> <Green d:type="sFloat32">0.7302905</Green> <Blue d:type="sFloat32">0.8672199</Blue> <Alpha d:type="sFloat32">1</Alpha> </cHcColour> </Colour> <Speed d:type="sInt32">110</Speed> </iTrackRulesBlueprint-sTrackSpeedLimitColours> <iTrackRulesBlueprint-sTrackSpeedLimitColours d:id="985"> <Colour> <cHcColour> <Red d:type="sFloat32">0.5278009</Red> <Green d:type="sFloat32">0.2448133</Green> <Blue d:type="sFloat32">0</Blue> <Alpha d:type="sFloat32">1</Alpha> </cHcColour> </Colour> <Speed d:type="sInt32">100</Speed> </iTrackRulesBlueprint-sTrackSpeedLimitColours> </TrackSpeedLimitColours>
That actually sounds like a really solid improvement project for AHS. The incorrect speed limits are one of those small details that completely break immersion once you notice them, especially on high speed routes where the difference between 230 and 320 km/h matters a lot operationally. The “undefined” texture issue above 200 is unfortunately something a lot of route builders run into because the default assets were never really designed around extensive LGV-style operations. You may need to create custom speed board textures or additional marker assets if the game only references generic IDs beyond 200. OpenRailwayMap is definitely a good reference source though, especially combined with cab ride footage and line documentation to verify transition points. Curious to see how the finished route turns out because the Channel Tunnel route has huge potential with more accurate signaling and speed profiles.