Flashing blue lights

[programmes1]

At Victoria there was flashing blue lights north and south of the station don't know any dates I'm afraid, anyone know what these were for?

[Tom]

The simple answer is no. I know they were installed around 1974 and lasted until about 1978 (and some of the wiring is still present in Victoria IMR), but they were never commissioned.

The original designer for the circuits is still around, if I run into him I'll ask.

[tubeprune]

According to the plan I have, the flashing blue lights were added in September 1978 (not commissioned) and removed July 1979. It doesn't say where they were.

[Tom]

I'll have a look at the original of that plan - I'm sure it's possible to see where they were.

[Deleted]

Forgive me for sounding thick, but what were the flashing blue lights actually for?

[Deleted]

Aug 18, 2008 0:32:56 GMT @theonekea said:

Forgive me for sounding thick, but what were the flashing blue lights actually for?

Yes, I was wondering that!

[Tom]

I'm sure we'd all like to know. See reply #1 - if/when I run into the person who designed the circuits I'll ask.

[mrfs42]

I have a hunch; and bear in mind that this is *just* a hunch that the lights were along the lines of a very early 'route proving' trial.

Possibly between VF3 and VF23 and vice versa, perhaps?

Whatever they were it'd be interesting to see what they were indicating.

[mrfs42]

BUMP! Any progress on this bit of esoterica-within-a-niche?

(Before anyone thinks this is a random bump, I've been searching through a lot of operating paperwork to no conclusive avail)

[railtechnician]

ISTR flashing blue lights being installed at Bank as part of the enabling works for DLR. IIRC they were installed in the Northern and Central tunnels and non-passenger areas of the station complex as indcators associated with movement detectors. There were a number of civil engineering issues at Bank, one of which was the concern that Monument station could break up as the DLR tunnel was bored. The answer, as explained to me at the time I was there diverting comms cabling, was to cut vertically through Monument station prior to commencement of DLR tunnelling to allow some flexibility and movement to occur. Movement detectors were strategically located to detect excessive or unwanted movement.
I am wondering if movement, subsidence etc was ever an issue at Victoria and if the flashing blue lights were there to indicate it.

[JR 15secs]

Sept 6, 2008 5:53:35 GMT railtechnician said:

ISTR flashing blue lights being installed at Bank as part of the enabling works for DLR. IIRC they were installed in the Northern and Central tunnels and non-passenger areas of the station complex as indcators associated with movement detectors. There were a number of civil engineering issues at Bank, one of which was the concern that Monument station could break up as the DLR tunnel was bored. The answer, as explained to me at the time I was there diverting comms cabling, was to cut vertically through Monument station prior to commencement of DLR tunnelling to allow some flexibility and movement to occur. Movement detectors were strategically located to detect excessive or unwanted movement.
I am wondering if movement, subsidence etc was ever an issue at Victoria and if the flashing blue lights were there to indicate it.

The flashing lights you refer to were installed at a number of stations for the reasons you stated but when operated following the alarm sent pre recorded messages and on the Central at least put or maintained certain signals at danger.