Signalbox diagrams - signal meanings

[Islineclear3_1]

I wondered if someone could remind me what a red semaphore arm with the end shaded black means on a signal box diagram. My memory tells me it is electrically operated (by the corresponding lever in the signal box) but the memory does play tricks on you as you get older.

Is there an on-line encyclopaedia I can refer to?

 

[Gloster]

I wondered if someone could remind me what a red semaphore arm with the end shaded black means on a signal box diagram. My memory tells me it is electrically operated (by the corresponding lever in the signal box) but the memory does play tricks on you as you get older.

Is there an on-line encyclopaedia I can refer to?

Yes, if the outer end is black then the signal is motor worked. At least, I presume that is standard as that is what is shown on a crib sheet for a long running series of articles in the Journal of the Cumbrian Railways Association on the resignalling over Shap fifty years ago. I believe the writer was a professional signal engineer.

 

[Islineclear3_1]

Thank you @Gloster for your (speedy) reply - the ol' brain cells are still working.

 

[zwk500]

Is there an on-line encyclopaedia I can refer to?

Openraildata wiki has the following PDF that might be of help (beware, it's comprehensive): https://wiki.openraildata.com/images/0/08/Signalling_symbols_2011.pdf

It's a copy of Network Rail's standard for the symbols to be used on plans and sketches used in signalling applications, the 2011 version. So note that things may have changed over the years, although it is largely consistent as the very nature of such drawings being safety-critical means that changes to existing symbols are generally avoided where possible to prevent misreading of older plans. This standard is primarily for the engineering drawings, rather than box diagrams above the frame/panel, so there may be differences there as well.

 

[matchmaker]

I've taken a look at an old photo of the diagram at Dalmeny Junction from the early 1970s. There were motor worked IBs between there and Saughton Junction. It's not particularly clear from the photo, but it looks as if the distant arm is simply yellow, with an annotation below "Electrically Operated". Unfortunately the stop signal isn't shown on the photo.

== Doublepost prevention - post automatically merged: 23 Sep 2025 ==

Just out of interest, here's a photo of the lever for the IB home and distant. My photo - sorry about the poor quality, but the negative is 50+ years old and developed by me. The lever was shortened, painted red and yellow, wth a black band.