What are these details?

[CaptOblivious]

What are these displays for, and what (and in what color) do they display? These are located near the outbound end of a platform (i.e., the driver will see them just as the train comes to a stop) serving Yamanote and Keihin-Tohoku lines.

 

From gmat's photographs of Akihabara Station:

[quashlo]

These are 出発時機表示器 (shuppatsu jiki hyōjiki).

When things are operating according to schedule, you won't see them in service at all. But when the schedule goes out the door (grade crossing incident, platform fall, etc.) and the train flow needs to be adjusted, these displays are used to instruct operators on what to do.

 

They have several different settings:

 

延発 (enpatsu): Depart later than usual

出発 (shuppatsu): Depart

抑止 (yokushi): Stop

通知 (tsūchi): Hold

etc.

 

There's a good explanation with pictures here:

http://kifpict.jakou.com/sghyouji.html

[bikkuri bahn]

They are departure indicators connected with JR East's ATOS traffic control system.  They are utilized when a disruption in the operating schedule occurs, and serve as an additional system (in addition to radio and direct staff to staff communication) to indicate whether a train can depart or not.  The (led?) color is orange, and are capable of displaying kanji and departure times.

 

This indication is "enpatsu", which indicates an extension of the departure to the indicated time (i.e. :28 15 seconds)

source: http://ja.wikipedia.org/wiki/%E6%9D%B1%E4%BA%AC%E5%9C%8F%E8%BC%B8%E9%80%81%E7%AE%A1%E7%90%86%E3%82%B7%E3%82%B9%E3%83%86%E3%83%A0

[CaptOblivious]

Great, thanks you two! Very helpful indeed.