To use the ABC technology with BM1, BM2 and BM3 block section modules, you will need locomotive decoders of the GOLD series or other decoders that support the ABC technology.
How does the ABC technology work?
With little effort, ABC manages to accomplish just what model railway enthusiasts crave: precise on-the-spot stopping in front of signals, slow approach and passage in the opposite direction.
By means of simple modules, which supply the braking section in front of a signal, an asymmetry is created in the otherwise symmetrical digital track voltage. Naturally, this occurs only if the signal is at "Stop" or "Slow approach". This asymmetry informs the locomotive decoder about the signal status: