This signaling device detects the metal flanges of wheels passing a specific point on the rail. By comparing the count at the entry point of a block with the count at the exit, the system confirms the entire train has passed. If the numbers do not match, the block remains occupied and signals stay red to prevent collisions.
Heard on the job
We've a mismatch on the axle counter at milepost 42, so the dispatcher is holding the eastbound local until we walk the track.
Insider tip
Axle counters replace traditional track circuits because they are less affected by wet ballast, rust, or poor electrical shunting.