Azuma Power Sockets - no power through neutral sections

AM9

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Its not the graphics card but the screen, many will change to a 50hz when plugged in (50hz is the frequency for mains sockets) but 60hz (what most monitors usually are) when on battery, this is what is causing the black screen for a couple seconds and is to be expected, every screen goes black a couple seconds when changing frequency. Others will stay at 50 or 60hz all the time and may convert the 50hz mains to 60hz although the software will auto dim the screen, it really just depends on how the laptop has been designed but both are normal behaviour and to be expected. ...
Every laptop/Notebook that I've ever used has been fed smooth DC from and external power unit. Thus the laptop doesn't know what a 50 or 60Hz supply is. Most computer screens have a 60Hz frame rate unless they are specialist games platforms where much higher refresh rates can be provided. The screen dimming is a function of the laptop's power 'plan', i.e. whether it is optimised for battery economy or performance.
 
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Bletchleyite

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Its not the graphics card but the screen, many will change to a 50hz when plugged in (50hz is the frequency for mains sockets) but 60hz (what most monitors usually are) when on battery, this is what is causing the black screen for a couple seconds and is to be expected, every screen goes black a couple seconds when changing frequency. Others will stay at 50 or 60hz all the time and may convert the 50hz mains to 60hz although the software will auto dim the screen, it really just depends on how the laptop has been designed but both are normal behaviour and to be expected.
The refresh frequency of the screen has no bearing on the power supply, as the mains power supplied to a laptop is fully rectified DC and has been for years, even on laptops in the 90s that had the PSU internally to the box.

I've not come across a laptop where the screen blacks out when you plug/unplug the power supply in years. Mine certainly doesn't (and it's a dirt cheap consumer HP), I have it set to the same settings regardless of the presence or otherwise of the power supply, it only dims when the battery runs low.
 

MotCO

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tell people not to use a high wattage appliance like a toaster on the train as they consume a lot of power.
I just have this vision of someone boarding a train with their Russell Hobbs toaster under one arm and a bag of Hovis under the other :D :D .

Although there was a picture in the papers a little while back of someone using a deskfan on the train - but presumably the electricity usage is minimal. Mind you, it sounds as though it will stop and start up to 44 times on the trip!
 

CrispyUK

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Some laptops have both a dedicated GPU and integrated graphics options, if the power plan is configured to use the dedicated GPU when plugged in for better performance, but integrated graphics on battery power for longer runtime, that would explain a momentary black screen whilst it switches between them.
 

AM9

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Some laptops have both a dedicated GPU and integrated graphics options, if the power plan is configured to use the dedicated GPU when plugged in for better performance, but integrated graphics on battery power for longer runtime, that would explain a momentary black screen whilst it switches between them.
Not seen one of them, but either way, the local ac supply frequency is independent of the screen refresh speed.
 

Energy

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I just have this vision of someone boarding a train with their Russell Hobbs toaster under one arm and a bag of Hovis under the other :D :D .

Although there was a picture in the papers a little while back of someone using a deskfan on the train - but presumably the electricity usage is minimal. Mind you, it sounds as though it will stop and start up to 44 times on the trip!
Far less, a 4 slot toaster is listed at 1500w, a desk fan is only 30w :)
Every laptop/Notebook that I've ever used has been fed smooth DC from and external power unit. Thus the laptop doesn't know what a 50 or 60Hz supply is. Most computer screens have a 60Hz frame rate unless they are specialist games platforms where much higher refresh rates can be provided. The screen dimming is a function of the laptop's power 'plan', i.e. whether it is optimised for battery economy or performance.
The refresh frequency of the screen has no bearing on the power supply, as the mains power supplied to a laptop is fully rectified DC and has been for years, even on laptops in the 90s that had the PSU internally to the box.

I've not come across a laptop where the screen blacks out when you plug/unplug the power supply in years. Mine certainly doesn't (and it's a dirt cheap consumer HP), I have it set to the same settings regardless of the presence or otherwise of the power supply, it only dims when the battery runs low.
Yeah, most get transformed to 12v DC by the external power brick and then lower to any other voltages required. However some electronics do get affected by the frequency, some will run a little slower on 50hz power although this will never happen on a laptop.
 

Zooty

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I went North from Kings Cross last week on an Azuma (June2020). Neutral sections seem to occur every 5 minutes at full speed on the train. That's approx 44 neutral sections between KX and the Scottish Border. Too bad if the battery in your equipment isn't working. 44 resets.
44? That seems awfully high. There's nowhere near that many on the WCML, although my knowledge is based entirely on listening to VCBs banging in and out on Pendos.
 

Bletchleyite

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Yeah, most get transformed to 12v DC by the external power brick and then lower to any other voltages required. However some electronics do get affected by the frequency, some will run a little slower on 50hz power although this will never happen on a laptop.
It is indeed possible to use the 50Hz frequency as a "timer" on cheap electronics, but as you say it's not applicable to laptops which have their own electronics for that purpose. A laptop is effectively isolated from mains variances (unless your battery is knackered).
 

stuu

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I've not come across a laptop where the screen blacks out when you plug/unplug the power supply in years. Mine certainly doesn't (and it's a dirt cheap consumer HP), I have it set to the same settings regardless of the presence or otherwise of the power supply, it only dims when the battery runs low.
My quite expensive Lenovo work one does, as does my cheap personal one, it hadn't even occurred to me that you could buy ones that didn't do that!
 

samuelmorris

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The way my surface is programmed is that if you disconnect power and then don't continue operating the screen, it assumes it's being taken with and blanks the screen after about 5 seconds, but you can wake it up instantly by pressing anything. If you were still typing when power went off it would carry on uninterrupted.
 

Domh245

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44? That seems awfully high. There's nowhere near that many on the WCML, although my knowledge is based entirely on listening to VCBs banging in and out on Pendos.
Based on the list on the railwaycodes website, I made it somewhere just north of 30 on the ECML. The WCML works out at around 30 as well, although with the WCML is helped in that regards by the (generally) more modern power supply, meaning fewer Neutral Sections as a result. ECML has lost a few recently as a result of power supply upgrades
 

AM9

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Far less, a 4 slot toaster is listed at 1500w, a desk fan is only 30w :)


Yeah, most get transformed to 12v DC by the external power brick and then lower to any other voltages required. However some electronics do get affected by the frequency, some will run a little slower on 50hz power although this will never happen on a laptop.
Laptop power supplies are designed for global use, and will usually guarantee the same DC power out over their stated input range of nominal voltages and frequencies, typically 100 to 240v ac and 50 to 60 Hz. In addition to those spreads, they will be type approved over the range specified by all the utility suppliers in those various countries, e.g., most of the low voltages have a +/- 10% range and those complying with the EU harmonised limits for 230v ac are +/-10% which covers both the standard 220v mainland and the Uk/Eire/ex British colonies and dependencies which were nominal 240v.
 

Roast Veg

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Some laptops have both a dedicated GPU and integrated graphics options, if the power plan is configured to use the dedicated GPU when plugged in for better performance, but integrated graphics on battery power for longer runtime, that would explain a momentary black screen whilst it switches between them.
This is the primary cause of screen blackout on modern laptops. For example, my Dell XPS 15 9550 has two GPUs: the Intel HD 530 iGPU and the NVIDIA GTX 960M dGPU. I have my system set up to use the dGPU exclusively for 2D and 3D high performance rendering (video and 3D modelling), and my displays are all connected to the iGPU.

Some laptops come preconfigured to switch between the high performance dGPU which consumes a lot more power and the iGPU when switching between battery and plugged in. On Windows 7 and above* you can create power profiles that control display settings, so creating a "on the train" profile with the options set appropriately to not turn off the dGPU would solve the issue.

*I do not use Windows anymore, having switched to Linux many years ago. I don't know where these options are any more, but I know that they exist.
 

Bald Rick

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I went North from Kings Cross last week on an Azuma (June2020). Neutral sections seem to occur every 5 minutes at full speed on the train. That's approx 44 neutral sections between KX and the Scottish Border. Too bad if the battery in your equipment isn't working. 44 resets.
There’s 30 between Kings Cross and the Scottish Border, including one at the border itself. In busy sections they can be quite close together due to power demand.
 

59CosG95

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There’s 30 between Kings Cross and the Scottish Border, including one at the border itself. In busy sections they can be quite close together due to power demand.
If any of you are lucky enough to have access to the ECML's isolation diagrams, this is essentially every feeder & mid-point track sectioning cabin between King's X & Marshall Meadows, with the exception of Potteric Carr Independent Feeder.
 

gallafent

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Yeah, most get transformed to 12v DC by the external power brick and then lower to any other voltages required. However some electronics do get affected by the frequency, some will run a little slower on 50hz power although this will never happen on a laptop.
I thought it was closer to 20V usually (Apple MagSafe2 goes up to 20V, for example, I remember seeing 18.5 and 19.5 maybe on older Windows notebooks) … and USB also goes to 20V too these days … but yes, it's definitely generally plain old DC down the wire from the power brick (and edit: maybe some signalling too, to configure the PSU to provide what the client device wants! edit: (I thought MagSafe did this but having started reading I'm not sure, perhaps the signalling from the computer is only to control the colour / activity of the LED in the plug!))
 
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Energy

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I thought it was closer to 20V usually (Apple MagSafe2 goes up to 20V, for example, I remember seeing 18.5 and 19.5 maybe on older Windows notebooks) … and USB also goes to 20V too these days … but yes, it's definitely generally plain old DC down the wire from the power brick (and some signalling too, to configure the PSU to provide what the client device wants!)
It varies but I think it is closer to ~18v looking it up, I put 12V as desktop PSUs have a 12V rail and then convert the voltage down for lower voltages.
 

AM9

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It varies but I think it is closer to ~18v looking it up, I put 12V as desktop PSUs have a 12V rail and then convert the voltage down for lower voltages.
Actually, the voltage that a notebook (or any lithium battery powered device) is determined by the voltage per cell (nominally 3.6V) and the number of series-connected cells. Most notebooks now have 5 series connected cells in the battery giving about 18V to drive the electronics. The ac adaptors usually give 1-2V higher than the battery voltage drive, so 19VDC is the most popular input voltage.
 

_toommm_

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This is the primary cause of screen blackout on modern laptops. For example, my Dell XPS 15 9550 has two GPUs: the Intel HD 530 iGPU and the NVIDIA GTX 960M dGPU. I have my system set up to use the dGPU exclusively for 2D and 3D high performance rendering (video and 3D modelling), and my displays are all connected to the iGPU.

Some laptops come preconfigured to switch between the high performance dGPU which consumes a lot more power and the iGPU when switching between battery and plugged in. On Windows 7 and above* you can create power profiles that control display settings, so creating a "on the train" profile with the options set appropriately to not turn off the dGPU would solve the issue.

*I do not use Windows anymore, having switched to Linux many years ago. I don't know where these options are any more, but I know that they exist.
Same with mine, although I have a MacBook Pro so I’ve got a dedicated AMD GPU and an Intel Iris something-or-other iGPU. I only really use the dedicated GPU for gaming or for Photoshop/Premiere; the iGPU can drive the 1600p screen for day-to-day stuff.

Ive got Windows 10 on it aswell as MacOS. The power options are available through the settings app, or it’s slightly quicker to go through the battery icon in the taskbar and viewing the different profiles.
 

Inthewest

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I recall many years ago (I think it was 2008 or 2009) I went to London with my family and my Dad took a rather old portable CD player. He didn't put any batteries in it and powered it from the 230V socket.
A portable cd player that gets plugged in?
Seems rather pointless.
 

AM9

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A portable cd player that gets plugged in?
Seems rather pointless.
They were really launched too early as the power needed was much more than cassette players and too much for primary cells to be cost effective, and a rechargeable technology to give sufficient power density wasn't available at consumer electronics prices. Thus charging secondary cells, which really only took off once GSM mobiles started to flood the market, wasn't in vogue in time for things like portable CD players.
 

jon0844

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I remember having a portable CD player and the battery life was pretty awful, so I also ran mine off mains power wherever possible. I even did so with a MiniDisc player for the same reason, and my Atari Lynx and Sega Gamegear also chomped through batteries. Heck, even my Casio pocket TV was on the mains power whenever possible.

Modern electronics and modern battery technology now means my tiny phone can give me 7-8 hours of screen on time and last from dawn to, well, dawn. I carry a power bank and/or mains charger but only as an emergency, or to keep a battery topped up during travel because I can then 'restart' the clock at the destination.
 

Tetchytyke

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A portable cd player that gets plugged in?
Seems rather pointless.
Nah, my Walkman used to eat AA batteries, so if I could plug it in to use it it was much better.

Battery technology has moved on so far in just a few years, thanks to smartphones pushing the tech along.
 

AM9

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Nah, my Walkman used to eat AA batteries, so if I could plug it in to use it it was much better.

Battery technology has moved on so far in just a few years, thanks to smartphones pushing the tech along.
So has the electronics moved on in leaps and bounds in power reqi=uirements.
 

ryan125hst

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The no power for neutral sections is to be expected, there are quite a few of these threads! The sockets for customers are just not considered important enough for the battery power and are a little unpredictable with how much power they will draw as it depends on the customers, whereas the kitchen/buffet can be easily predicted. Companies don't really care about the sockets not working for a few seconds, to stop it would require considerable expense in extra batteries and they always have a sign up by the socket saying only mobile phones and laptops so it is assumed that your device will have a battery in it and won't mind a couple interruptions in the mains, although these signs are mainly to tell people not to use a high wattage appliance like a toaster on the train as they consume a lot of power.
I'd imagine the power hungry three phase cookers go off regardless though as to provide power for them from a battery would be expensive and impracticable? What surprised me the most was how the sockets on the 225 sets which were retrofitted in the mid 2000's during Project Mallard are backed up by batteries and yet they go off on an Azuma, despite improvements in battery and inverter technology since then. There will be a reason for it, probably cost or maybe the electrical configuration of the Azumas compared to the 225's, but it seems odd.
 

James James

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I'd imagine the power hungry three phase cookers go off regardless though as to provide power for them from a battery would be expensive and impracticable? What surprised me the most was how the sockets on the 225 sets which were retrofitted in the mid 2000's during Project Mallard are backed up by batteries and yet they go off on an Azuma, despite improvements in battery and inverter technology since then. There will be a reason for it, probably cost or maybe the electrical configuration of the Azumas compared to the 225's, but it seems odd.
You answered it yourself: cost. Adding battery capacity just for power sockets is, plain and simple, more expensive and (IMHO) a waste of money since it's not needed by most people.

Also, isn't LHCS generally likely to have more battery capacity because they're expected to be left without a power supply for certain amounts of time (e.g. when swapping locos, doing turnarounds), whereas D and EMUs can almost always supply themselves with the exception of faults, and EMUs being taken off the wires (not a routine operation). To be fair, I have no idea how the Mk4 was designed, I presume they knew how they'd be operated, but for older LHCS certainly battery capacity was more important, hence would be more extensive than on modern multiple units.
 

gimmea50anyday

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Bear in mind when being tugged by a 67, catering cannot be provided as the power requirements for the SV is higher than what the 67 can put out

I haven’t noticed any blackout or switches on my ASUs FX505D (Ryzen 5, Nvidia 1660GTX) although the screen brightness changes and I get the battery/plug icons for about 3 seconds so I suspect the OP needs to go through their system settings and tweak them a bit. The only real issue I have noticed with electronics seems to affect iPads plugged into the mains or USB supply on an 80x as an iPad touchscreen is capacitive they don’t work!
 

ryan125hst

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Also, isn't LHCS generally likely to have more battery capacity because they're expected to be left without a power supply for certain amounts of time (e.g. when swapping locos, doing turnarounds), whereas D and EMUs can almost always supply themselves with the exception of faults, and EMUs being taken off the wires (not a routine operation). To be fair, I have no idea how the Mk4 was designed, I presume they knew how they'd be operated, but for older LHCS certainly battery capacity was more important, hence would be more extensive than on modern multiple units.
I'm not sure of how the Azuma's are wired electrically but my understanding is the Mark 4's have a battery that supplies power for the door circuits, PA and lighting and I always assumed that it was this battery that the inverters for the 230V AC supply are connected to that supply the sockets. There will be a battery in each coach and when the ETS drops out at a neutral section the inverter continues to operate. Presumably there's some sort of load shedding capability to save power for the emergency lighting and PA should the ETS be off for too long?

Maybe the Azuma's have a battery that supplies multiple coaches and so this arrangement wouldn't be practical?

Bear in mind when being tugged by a 67, catering cannot be provided as the power requirements for the SV is higher than what the 67 can put out
I think I have read somewhere that some coaches (Mark 3 Loco Hauled?) have a catering low load switch that reduces the catering electrical demand. Do the Mark 4's have something similar or does all catering, even the buffet, have to stop?
 

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