detection, brake and stop blocks

Automatic control of a DCC layout controlled by Railroad and Co demands that the system knows were the trains are at key points and that messages can be passed to the locos to slow down and stop/start.

These are achieved by a block system.

Detection blocks are provided in a similar manner and will read once a locomotive enters it. It is also possible to detect that the last vehicle has entered the block by placing a small resistor between the last pair of wheels. Due to the small size, this has not been done on County Gate and we rely on the integrity of our Greenwich couplings.

The cut rails for blocks must always be on the same rail (control rail). Once the first current collection wheel passes onto a block, the message to slow down, stop or start is received.  Positioning of the stop block is critical to ensure that all trains stop in the correct positions. With conventional locomotive hauled trains, this is not difficult. Our railcars on the other hand did present a problem as the current collection is from the central motor car. To solve this problem, the bogies on the passenger cars had to be modified so that there was current collection from the control rail.