Good day folks,
For signal logic, my understanding is that, if one uses the NO input, if a circuit is closed, then the signal drops to red. This is good for ABS/occupancy detection. If one uses NC, then if the circuit opens, the signal drops to red. This is good for showing if a turnout is lined against the movement.
I would like to incorporate two separate block detectors, and a detector for switch position, onto the same signal. To that end, if I wire the detection circuit in parallel (as opposed to series), would closing one ladder of the parallel close the circuit, and cause the signal to change aspects (if using NO)? Basically, I want to create a logic such that, if there's a car in either of the two blocks, or if the switch is not lined for the CTC-controlled mainline, it drops to red.
Context:
I'm planning a shelf layout for a back room. I have plans to make a light rail line that uses ABS/CTC, which interacts with a Rule 171/unsignaled secondary line and spurs. The light rail line runs from the tunnel/staging at left middle to a planned platform in the bottom right. The heavy rail switcher would enter the CTC-controlled lines to work the various sidings or run around cars, so they might leave cars in the block, enter the non-CTC line that crosses the diamond, then reenter the block.
I'm planning for four very short blocks: light rail staging (B5), from the tunnel mouth to the diamond (B4), from the diamond to the lower right tail track (B2) and the platform itself (B1). The red arrows show the position of signals protecting movements along the CTC route, with the blue line representing the two blocks I'd like displayed by one head at the diamond for EB moves. This is partially aesthetics, since I don't want one signal right after another, and partly practicality, since there's not enough room for a trolley between the diamond and the next block, and it wouldn't make sense to have the trolley stop on the diamond, when the heavy rail switcher might need to move across it to clear the block.
