so this means it will be very easy for passengers to tell when the train is ready to depart?
on another note, will the current acceleration rate increase once the new signalling is active? (like on the jubilee/victoria/central lines)
Yes I expect some passengers will learn the meaning of the white lights, just as they learn the meaning of the current starter signal or the platform repeater of it, and indeed some passengers learn the meaning of the platform RTDI lights on the Jubilee and Northern lines. The RTDI lights will come on about 10 seconds before timetabled departure time.
On accelerating rates, there is more acceleration capability on the S stock trains in ATC modes. ATC Auto may not use all of it all the time. It may use more like the present rates in areas subject to lower adhesion. The settings are programmable and also adjustable at 'central'.
The blue light takes the place of the white light when de-icing fluid is being sprayed, in the upper quadrant. I'll try and upload a photo later on.
To revisit the white lights... I've asked around and the understanding is that white lights still behave as I originally posted even on ATC-modified trains - that is, a solid white light appears when a PEA is pulled and the flashing behaviours currently inhibited. The change won't actually take place - as originally posted - until the first ATC sections start to go live and the train is operating under CBTC. I am seeking further clarification on this (and a little annoyed I didn't think of those earlier this week when I had the opportunity to test the operation of a PEA on an ATC-modified train!).
It occurs to me that blue and yellow are mutually exclusive; Blue is extinguished when the doors are unlocked and yellow illuminates. If a PEA is activated on a train spraying fluid and in motion, does the white illuminate (and blue extinguish)? Or does that only happen once the train has stopped? It seems odd that the two colours that could illuminate together are in the same cluster and require some switching and the two colours that are mutually exclusive are in separate clusters?
A fair bit of work has gone into deciding the precedence of the various indications. There's not really an issue with the blue and white. The blue indication is only significant to anyone between stations and the white (flashing or steady) at stations.
I know this is going to sound unbelievably sad but are the white/blue indications colour changing LEDs or two types arranged alternately? Also is every unit deicer fitted or only select units?
It would be quite unusual to get blue/white colour changing LED's as blue can be produced naturally but white is either a mixed or fluorescent effect. (And although mixing is technically possible, it would yield a blue light much dimmer than the white.)
All 'colour changing' LED's are actually multiple LED's in the same package - the required colours being energised as required, so there is no logical difference between, say, a red/green colour changer and having two separate components, although the former is often neater in various ways. (i.e. wiring/mounting/more even coverage.)