There's a lot of fairly speculative discussion going on around here at present.
Firstly, "thinking outside the box".
The operating rules and regulations of the railways are there to ensure the safety of staff, passengers, trains and infrastructure. Therefore they are all there for a very good reason. Flexing, circumventing or just plain ignoring them increases risk to the extent that safety becomes compromised. When normal operating procedures go out the window, e.g. as a consequence of signal failure, other rules kick in to permit continued operation with the same degree of safety even under degraded conditions.
While it's quite nice to think that you're doing everyone a favour by keeping the job moving, it's a very fine line to tread. The moment you start ignoring the rules and regulations you have impaired safety and have started out on a tightrope. If all goes well then so much the better, but if it goes wrong then you're properly in the mire.
As an example, if I get to my break point late and don't have time to take the full 40 minutes I'm entitled to, I can either opt to take a spoilt break and be compensated in my pay or I can run my next service late. I know which option most members of the travelling public and the company would like me to take, but in doing so I am ignoring the rules and impairing safety. If I take the spoilt break I am potentially introducing a greater degree of risk. If I happen to SPAD a signal following a spoilt break the fact that I have agreed to take the shorter break "as a favour" would not count for me. The SPAD would go down against my name and the major factor would be that I failed to take my break. If I happen to collide with another train and kill lots of people I could be personally liable under law for criminal proceedings against me on the basis that I needlessly introduced risk.
Consequently, rules are there for a reason. You can't just try one thing and, if it doesn't work, try something else. The rules and procedures are intended to ensure safety.
Secondly, Eurostar's emergency procedures.
I have already said in this thread that the failure of 5 sets in "the pipe" at the same time is about the same odds as winning the lottery. The fact that it has happened only once in 15 years highlights just how unusual this is. Consequently, how do you plan for what must have been considered "the impossible"?
Thirdly, Eurostar on-train power.
I am not familiar with the workings of the Eurostar, but as most know I do at least "sign" electric traction.
I would imagine that snow ingress would have caused a flashover somewhere which would have tripped an overload relay and opened the VCB, thereby protecting the train. Depending on precisely what the fault was, putting the VCB back in would probably have resulted in a second flashover and the VCB tripping again. With new stock like the Eurostar I would imagine that these functions would have been under the control of the TMS which would no doubt limit the number of VCB resets attempted.
What happens next would depend on precisely what and where the fault was. I know that often times you get a motor or earth fault that only manifests itself when you open the power controller so, provided you don't attempt to draw power you can sit there with the VCB in quite happily. However, if the fault is elsewhere, particularly with the transformer or other "stationary" systems, you won't get the VCB back in no matter what you do. Again, on Eurostar, I suppose it all depends on what the TMS permits, whether the affected systems can seperately isolated and whether or not the flashover on the train was sufficiently severe to cause an overload on the traction supply and trip out the overheads as well.
Eurostar will have their own fault-finding procedures that would have been followed. There is a fair chance that damage to the pan may have been suspected (especially if the driver saw a bright flash) and so they were lowered as a precaution.
Fourthly, "winterisation" of the sets.
I have no reason to doubt Eurostar's statements on this front. Even proven designs that had been in service for a number of years can suddenly succumb to unexpected, or at least unexpectedly bad, weather conditions. We blew quite a few traction motors on Cl317's last winter when it snowed, and these units have been in continuous service somewhere between 25 and 30 years.
Now that Eurostar know that the existing snow screens are not adequate for all winter conditions they will be changed.
Fifthly, the blame game.
Everyone loves to play this whenever something bad happens. Quite frankly I'm not going to join in because I find it tiresome and those who seem to want to take the lead seem to know the least. What should or shouldn't happen as a result of this incident will be looked at when these failures are investigated and recommendations made were necessary.
Re: pans and VCBs; the detail is gibberish to me, but I think I understand the overall picture: it is possible for a fault with the traction system to disable the non-traction supply. If the traction supply is utilised to supply non-traction life safety services eg lighting, then there is an element of value engineering here. The belt and braces approach would be to fully separate traction and non-traction supplies.
If the detail is gibberish to you I don't see how you can comment on whether or not the engineering is good, bad or indifferent. Clearly you have no understanding of how electric trains operate, so perhaps you ought to either withdraw from this part of the discussion, go away and do some reading or be willing to ask someone with a bit of knowledge to explain it to you.
With respect...
O L Leigh
