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All across the Great Western territory => Across the West => Topic started by: broadgage on January 09, 2019, 03:12:30



Title: Station lighting fails at Paddington.
Post by: broadgage on January 09, 2019, 03:12:30
Media reports state complete failure of station lighting last night.
The only illumination was from the lighting in the many retail units.

Does not look like a general failure of the public electricity supply since said retail units still had power.

Have network rail not heard of standby generators ? Or a secondary electricity supply derived from the traction current? or even of dividing station lighting between two different supplies on different substations ?

https://www.bbc.co.uk/news/uk-46804914 (https://www.bbc.co.uk/news/uk-46804914)


Title: Re: Station lighting fails at Paddington.
Post by: JayMac on January 09, 2019, 03:15:19
Have network rail not heard of standby generators? Or a secondary electricity supply derived from the traction current? Or even of dividing station lighting between two different supplies on different substations?

Or putting 50p in the meter?


Title: Re: Station lighting fails at Paddington.
Post by: TaplowGreen on January 09, 2019, 05:05:30
Have network rail not heard of standby generators? Or a secondary electricity supply derived from the traction current? Or even of dividing station lighting between two different supplies on different substations?

Or putting 50p in the meter?

The railways always keep everyone in the dark when there are problems, perhaps this is a new strategy?  (........or was M Hopwood travelling through Paddington and wished to stay incognito?)


Title: Re: Station lighting fails at Paddington.
Post by: nickswift99 on January 09, 2019, 08:29:04
Not quite on the same scale but a complete power failure at Goring & Streatley yesterday morning. Meant that the station was in complete darkness from 0300 until daylight, the emergency lighting having been completely depleted before any services started.

No announcement on JourneyCheck so anyone travelling in the down direction hoping to use the lifts would have been stranded.

I'm not sure how well DOO works in complete darkness on 165s and 387s but at least services were still stopping.


Title: Re: Station lighting fails at Paddington.
Post by: stuving on January 09, 2019, 09:33:23
Media reports state complete failure of station lighting last night.
The only illumination was from the lighting in the many retail units.

Does not look like a general failure of the public electricity supply since said retail units still had power.

Have network rail not heard of standby generators ? Or a secondary electricity supply derived from the traction current? or even of dividing station lighting between two different supplies on different substations ?

https://www.bbc.co.uk/news/uk-46804914 (https://www.bbc.co.uk/news/uk-46804914)

From the reports, it sounds more like a switchgear failure within the station. For example, a breaker protecting part of the roof lighting trips, and can't be reset. Electricians come and prod it, and conclude it needs replacing, but that means removing power from its input - which feeds all the lights in the whole station. Thus the station is in darkness (reported as from 23:20) until the replacement is finished. There might be some scope for splitting circuits so a single failure leaves more lighting still on, though there are limits on that both as to remaining single points of failure and, I suspect, also from the need for safe working.

I would ask instead why there appears to be no emergency back-up lighting, even a limited amount of it, which would probably be best fitted on the platforms.


Title: Re: Station lighting fails at Paddington.
Post by: Electric train on January 09, 2019, 10:40:53
Paddington station has its own high Voltage network derived from 3 dedicated in feeds from the DNO, the main substation is located outside the main train shed (I know where but will not say)

The main station lights are controlled by a substation under the booking office on platform 1 it also has a feed from an adjacent substation also there was a generator (not sure if this has been kept)

I used to be part of the station maintenance back in BR days

The weaknes with all electrical change over system is the change over panel 99.9% reliable but like all things there will be a once in 30 years a total failure built into the desing risk.


Title: Re: Station lighting fails at Paddington.
Post by: Dispatch Box on January 09, 2019, 11:56:11
Paddington station has its own high Voltage network derived from 3 dedicated in feeds from the DNO, the main substation is located outside the main train shed (I know where but will not say)

The main station lights are controlled by a substation under the booking office on platform 1 it also has a feed from an adjacent substation also there was a generator (not sure if this has been kept)

I used to be part of the station maintenance back in BR days

The weaknes with all electrical change over system is the change over panel 99.9% reliable but like all things there will be a once in 30 years a total failure built into the design risk.


I always thought Paddington also had a backup system to power the lighting and platform screens, but I suspect this did not come in,as the fault was not outside in the Paddington area of London.

In Gloucester they were all in one box, that at one time the chargeman used to flick up all the breakers then the lights came on. Now are controlled from a shields box with a red light on. Some of the platform lights now have photocells.


Title: Re: Station lighting fails at Paddington.
Post by: patch38 on January 09, 2019, 12:19:36
The weaknes with all electrical change over system is the change over panel 99.9% reliable but like all things there will be a once in 30 years a total failure built into the desing risk.

And it sometimes takes a really bizarre set of circumstances to stress test the system as the BBC discovered in 2007 when they lost the entire national FM network (Radios 1 - 4) one Saturday afternoon. Even though there was a fully redundant backup distribution system in place nobody was aware that both signal paths ran through a single building at one point (which they shouldn't have done, but nobody had spotted it). The air conditioning failed in that building and took out both paths with the resulting loss of feed to the entire network of FM transmitters. Chaos for a while until the backup to the backup kicked in.

Nothing in this world is 100% reliable!


Title: Re: Station lighting fails at Paddington.
Post by: Dispatch Box on January 09, 2019, 13:13:40
Have network rail not heard of standby generators? Or a secondary electricity supply derived from the traction current? Or even of dividing station lighting between two different supplies on different substations?

Or putting 50p in the meter?


Or GWR have not paid the bill.


Title: Re: Station lighting fails at Paddington.
Post by: ellendune on January 09, 2019, 13:48:48
Have network rail not heard of standby generators? Or a secondary electricity supply derived from the traction current? Or even of dividing station lighting between two different supplies on different substations?

Or putting 50p in the meter?


Or GWR have not paid the bill.

Paddington is run by NR so presumably GWR is not responsible for paying the bill. 


Title: Re: Station lighting fails at Paddington.
Post by: broadgage on January 09, 2019, 16:23:22
Changeover controls are indeed themselves a potential point of failure, and should IMHO be avoided when possible for lighting.

A better approach for large stations is to connect roughly alternate lamps to different supplies, without any changeover panel. Failure of either supply would still leave half the lights lit.

If changeover controls are needed, these should be duplicated with each set supplying half the lamps.

For example "odd numbered lamps" are normally supplied from substation #1 but change over to substation #2, if #1 fails
"even numbered lamps" are normally supplied from substation #3 but changeover to substation #4, if #3 fails. These two sets of changeover switchgear should be in different locations, to protect against fire or other accident affecting both.

Failure of any one supply leaves 100% lighting. Failure of either set of changeover switchgear leaves 50% lighting.

If BOTH sets of lights go out, for example due to a large scale external power cut, then a third set of lamps that are normally unlit should come into operation.
These would be of much reduced power, about 2% of normal lighting levels will suffice in an emergency, possibly less.
A rule of thumb for emergency lighting in large open plan areas is about one tenth of a watt per square meter.
That relatively modest loading may be obtained from a generator.


Title: Re: Station lighting fails at Paddington.
Post by: Electric train on January 09, 2019, 18:17:37
Changeover controls are indeed themselves a potential point of failure, and should IMHO be avoided when possible for lighting.

A better approach for large stations is to connect roughly alternate lamps to different supplies, without any changeover panel. Failure of either supply would still leave half the lights lit.

If changeover controls are needed, these should be duplicated with each set supplying half the lamps.

For example "odd numbered lamps" are normally supplied from substation #1 but change over to substation #2, if #1 fails
"even numbered lamps" are normally supplied from substation #3 but changeover to substation #4, if #3 fails. These two sets of changeover switchgear should be in different locations, to protect against fire or other accident affecting both.

Failure of any one supply leaves 100% lighting. Failure of either set of changeover switchgear leaves 50% lighting.

If BOTH sets of lights go out, for example due to a large scale external power cut, then a third set of lamps that are normally unlit should come into operation.
These would be of much reduced power, about 2% of normal lighting levels will suffice in an emergency, possibly less.
A rule of thumb for emergency lighting in large open plan areas is about one tenth of a watt per square meter.
That relatively modest loading may be obtained from a generator.

The lighting at all major stations has emergency lighting, however this is only sufficient to allow the evacuation of the station, it is not sufficient to operate the train service.   The lighting switches at Paddington in the days I was involved in the maintenance, and these were manual switches which station staff turned on and off as required.  The switches were arranged such that the station staff naturally had alternate platform rows of lights fed from two different substations, the HV network was normally arranged such that these substations were fed as separately practical.

I don't know the current control system which is automatic with manual overrides, but I suspect it was designed with supply integrity in mind.  The integrity of the supply, control system or switchgear may have been compromised by accident or due a project or fault.


Title: Re: Station lighting fails at Paddington.
Post by: bobm on January 09, 2019, 20:10:25
Also had an effect on train running as the red lamps on the stop blocks at the head of platforms 1-8 failed.  That was solved by placing Bardic lamps on the buffers to guide trains in under caution.


Title: Re: Station lighting fails at Paddington.
Post by: lordgoata on January 10, 2019, 10:43:08
I'm not sure how well DOO works in complete darkness on 165s and 387s but at least services were still stopping.

Ollie was frustrated, SSE had said the power would be back on by 6am, but was still off at 645am when I left. He wanted to be on both platforms at once to assist the drivers in leaving.

Interestingly enough, the lift on platform 2/3 had its light still on, whilst everything else was off. I am surprised it was not closed for 'elf & safety, it was pretty sketchy wandering along the platforms in the pitch black!

PS. I tried to upload the photo I took (295KB) but when I click Post I just get a blank screen and nothing happens, will PM grahame


Title: Re: Station lighting fails at Paddington.
Post by: broadgage on January 10, 2019, 10:48:09
Also had an effect on train running as the red lamps on the stop blocks at the head of platforms 1-8 failed.  That was solved by placing Bardic lamps on the buffers to guide trains in under caution.

Back in the good old days, such lamps would have been duplicated, one oil lamp in case of power failure, and one electric light in case the someone forgot to fill the oil lamp.


Title: Re: Station lighting fails at Paddington.
Post by: Dispatch Box on January 10, 2019, 11:54:42
Also had an effect on train running as the red lamps on the stop blocks at the head of platforms 1-8 failed.  That was solved by placing Bardic lamps on the buffers to guide trains in under caution.

Back in the good old days, such lamps would have been duplicated, one oil lamp in case of power failure, and one electric light in case the someone forgot to fill the oil lamp.

Stop lamps today like the ones in Gloucester seem to be L.E.D. type emergency fittings with just red covers on. And set to be maintained, I.E on all the time.


Title: Re: Station lighting fails at Paddington.
Post by: nickswift99 on January 10, 2019, 14:07:22
I'm not sure how well DOO works in complete darkness on 165s and 387s but at least services were still stopping.

Ollie was frustrated, SSE had said the power would be back on by 6am, but was still off at 645am when I left. He wanted to be on both platforms at once to assist the drivers in leaving.

Interestingly enough, the lift on platform 2/3 had its light still on, whilst everything else was off. I am surprised it was not closed for 'elf & safety, it was pretty sketchy wandering along the platforms in the pitch black!

PS. I tried to upload the photo I took (295KB) but when I click Post I just get a blank screen and nothing happens, will PM grahame

We were probably on the same train. Ollie definitely shows the value of having a staffed station.


Title: Re: Station lighting fails at Paddington.
Post by: Dispatch Box on January 10, 2019, 16:02:20
I have thought of something, that happened in 2017 in June, The power went in Gloucester station knocking out the lights, and the cis screens, anyway someone said, 'HAS ANYBODY GOT A SHILLING FOR THE METER', Everyone laughed.



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