Coming Soon:

CurrentSense

I have been giving a lot of thought to specific problems we ran into when implementing the Automatic Block Signal System.

The BIGGEST problems we ran into was how to sense trains in the Trestle and the Tunnel modules.

The Trestle module is in full light, but the construction is so delicate that we didn't want to touch the track on the actual trestle.

The Tunnel modules have the problem of being DARK so light sensors can't see light without adding lights or IR emitters in the tunnels.

Lights make the tunnel look weird and IR emitters require a bit of accuracy and pretty much one emitter for each sensor.

My solution is to use current sensing in every block you design. Now, before you start screaming that you want to go photo based so you don't have to add resistors to each car in your fleet, here is my solution:

Use a pair of normal photo sensors at the beginning and end of the block and then use the current sense board to only sense the ENGINE which requires no additional modification to the rolling stock. The current sense board sees the ENGINE while it is in the block and the photo sensors will handle seeing the cars after the engine has left the block which will keep the block signal accurate. We need to add two sensors at the beginning of the block to counter the flicker caused when the engine switches from one current source (block) to the other (there is a brief period where the engine is powered by BOTH blocks and that causes fluctuations in the signal).

I have a DC based layout using this solution and will be testing a DCC version soon.

Although this is an in-line detector, I am working on a less intrusive solution using coils to detect the current draw. This will eliminate any problems with shorts or engine speeds that could cause the trains to perform below expectations.

I will offer both detectors as DUAL CurrentSense Boards since it is almost the same price as a single and a lot of you have multiple tracks in one block. You can always use it for adjoining blocks in the event of single track layouts.

The board is 3.2" x 1.5"