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0 pointsmschuster911y ago0 comments

> And, yes, twenty five years ago SelTrac was cutting edge. Moving block systems were basically unheard of back then.

Meanwhile in Germany, we have had moving blocks from the late 80s, based on a technology developed from the mid-60's and production-ready by the 70s [1]. Incredibly, the LZB technology never had an actual accident happen in all the time, only three "bare misses" (one of which was pretty spectacular in that it caused a train to pass over a switch rated for 80 km/h with around 185 km/h without derailing).

[1] https://de.wikipedia.org/wiki/Linienf%C3%B6rmige_Zugbeeinflu...

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rexpress1y ago

SelTrac has been around since the mid 80s, and was originally a German developed product (Standard Elektrik Lorenz) based on LZB technology.

My understanding of LZB is limited, but it appears to be a fixed block system with wayside detection of trains, albeit with shorter blocks than lineside signals would usually have. This is different to SelTrac which is moving block.

mschuster91OP1y ago

Yeah, LZB internally is based on fixed blocks - but on a system with block lengths down to 50 meters (as in the Stammstrecke München [1]), the difference is negligible.

Crazy to see that SelTrac was actually developed in Berlin, failed there, but is still in widespread use across the world.

[1] https://de.wikipedia.org/wiki/Stammstrecke_(S-Bahn_M%C3%BCnc...

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