The "No Right Turn" sign illuminates when any train passes Division St., activating the RR X-ing signal & gate. All other lights at the interchange also remain red during this cycle except for the right-turns away from the RR X-ing. 12 commuter trains and 1 freight train activate this system on a daily (weekday) basis.
This cycle is also what is causing the peak-hour gridlock 1 block west at the intersection of Division St. & Atwater/Clifton Aves. We are attempting to tie that signal into the Pershing signal to avoid that issue as well but they are completely separate systems; one owned by Ansonia and the other by the DOT and there is no conduit connecting them.
As for adding a second lane to Division St. (East) from Pershing to the RR X-ing, there are no plans at this time although striping into and out of the former Eblens Plaza might provide for more effective capacity. The taking of private property to accomplish a full second lane is not justified by the minimal increase in capacity. Division St IS currently two lanes in both directions from the RR X-ing to Route 115 on the other side of the Naugatuck River.

Okay, now that you've confirmed why/when it illuminates - does that come on only when the Pershing traffic has the red? (to permit west bound Division to clear out in the event someone was silly enough to stop on the tracks)....

If so, that basically means my interpretation was correct - that it means "no right turn on red" since the sign only lights up when the signal next to it is red.

Thank you for the quick response.

Now if we can remove the shrubs that block the view pulling out of the division street entrance from the shopping center. Yesterday, they seemed to be trimmed back, but that is often not the case. Difficultly getting in and out may be at least part of the reason that shopping center is almost completely unoccupied now.

Purpose of the sign makes sense