nyc subway signal identification

[rail10]

How can I tell if the signal is automatic or an interlocking one?

[RearOfSignal]

Home signals (signals with multiple heads) are interlocking signals. These govern the entrance to interlockings. These are easy to distinguish because of the multiple heads.

Approach signals however, usually have only one signal head, and operate in a similar manner to automatic signals. They are usually seen before or when approaching interlockings or terminals. The condition of approach signals are affected by the conditions set by the tower at interlockings, but are not absolute (they can be set to show 'Stop' but they can be passed at slow speed or 'keyed by'). Approach signals are controlled off the same lever and can the control length can span over multiple signal blocks.

Basically, if you ride from the head-head enough you can tell which ones approach signals; usually by seeing two or three consecutive stop signals, very close together when there is no train inside the signal block.

Check out www.nycsubway.org/tech/signals it explains it all pretty thoroughly.

[DaveBarraza]

NYCT controlled signals have a plate with the letter "X" and the lever number of the signal.

2 head interlocking (home) signals have this plate on the front.
1 head interlocking (approach) signals have this plate on the side.

[pdtrains]

I seem to remember that some of the old signals on the IRT and BMT had 1 head interlocking signals. Usually protecting a trailing point switch, where there is no "diverging route". These signals may all be gone by now.

Does anyone (besides me) remember the lower quadrant semaphores on the Jerome Ave and New Lots lines???

[Crabman1130]

I seem to remember that some of the old signals on the IRT and BMT had 1 head interlocking signals. Usually protecting a trailing point switch, where there is no "diverging route". These signals may all be gone by now.

Does anyone (besides me) remember the lower quadrant semaphores on the Jerome Ave and New Lots lines???

When I used to ride down Linden Blvd I could see the semaphores. I never knew why they were different from the other subway signals.

[RearOfSignal]

I seem to remember that some of the old signals on the IRT and BMT had 1 head interlocking signals. Usually protecting a trailing point switch, where there is no "diverging route". These signals may all be gone by now.

On the IRT Dyre line I think they still have a 1 head interlocking signal protecting a trailing point switch just south of Morris Park, downtown track.

[DaveBarraza]

seem to remember that some of the old signals on the IRT and BMT had 1 head interlocking signals. Usually protecting a trailing point switch, where there is no "diverging route". These signals may all be gone by now.

There was one at Fisk that was removed from service in the last year. There may be one or two at E180th which are in the process of being replaced now.