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GWR Class 800

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najaB

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And what's in the box then? Please enlighten me. If I were a betting man I'd be willing to bet it's going to be in line with most other embedded systems, and given that most embedded systems favour stability, most hardware and software will be older and more mature so to speak.
Yes, the hardware may well be old but ETCS is not. Hence the technology (hardware+software) is not.
 
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asylumxl

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Not a trade off but a feature of the connector as you said and I'm not claiming it's new technology but maybe in this application it's appropriate technology; furthermore to compensate for reduced noise immunity with extra shielding is poor design.

What connectors do you think should be used?
Krus_aragon said the following:

It sure can be, especially for new technology

Which is what my reply was in response to, which you decided to latch on to. So yes, you're either trying to argue it's new or your reading comprehension skills are questionable.
--- old post above --- --- new post below ---
Yes, the hardware may well be old but ETCS is not. Hence the technology (hardware+software) is not.
The original specification dates back to 1996, while the first tests were 1999. That's 20 years.
 

coppercapped

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I'm pretty sure non ATP maximum is 100mph.

Are you to referring to the GW in particular or GB railways in general? Only the GW and the Chiltern routes have ATP and of these two only the GW operates at over 100mph. The Midland, West Coast and East Coast main lines are not equipped with ATP yet operate at speeds up to 125mph, so clearly ATP is not essential for operation in excess of 100mph.

As you know the Relief Lines between Reading and Didcot East are passed for 100mph and the Cross Country services are therefore timed at this speed - even if sometimes they run on the Mains. However, a couple of years ago I was on a Voyager running (a bit late) from Oxford to Reading which was routed on the Mains from Didcot - I timed it at over 100mph (about 110/115 if I remember correctly) so there may not be an absolute 100mph limit for non-ATP equipped stock on the Western.
 

krus_aragon

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But it's not new technology is it? The RF connector is positively prehistoric. As for the RS232 DB25 connector, it's seriously outdated.

Neither are as anywhere near as dated as the headphone jack: the full-size 1/4-inch variety was first used in the 1870s for telephone switch boards. (Thank goodness that Apple has finally started getting rid of them from their new devices!)
 

asylumxl

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Neither are as anywhere near as dated as the headphone jack: the full-size 1/4-inch variety was first used in the 1870s for telephone switch boards. (Thank goodness that Apple has finally started getting rid of them from their new devices!)
Yes, it's not like RS232 is also a standard for serial communication as opposed to just a connector, right? Totally comparable. ;)
 

JN114

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To clear up the ATP restriction:

It's a General Instruction in the Western Sectional Appendix; the limit is 110 not 100 (albeit I believe it was raised recently); it does NOT apply between Reading and Didcot and is worded thus:

"TRAINS NOT FITTED WITH AUTOMATIC TRAIN PROTECTION (ATP) - MAXIMUM PERMITTED SPEED

Trains not fitted with ATP may travel at permissible speeds between Reading West Junction and Didcot East Junction on the main lines. Over all other sections of line shewn in Table A of this Sectional Appendix as being ATP fitted, the maximum speed for all trains not fitted with ATP must not exceed 110mph at any point.

This restriction is due to design limits of TPWS lineside equipment for trains fitted only with that system."

Sectional Appendix Supp32 - 03/09/16; Module WR1; Page 79 for those that have Up-to-date access.
 
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krus_aragon

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Yes, it's not like RS232 is also a standard for serial communication as opposed to just a connector, right? Totally comparable. ;)

I suppose you have a point there, but there other types of data shoved through d-subminiature ports. And I think my point still holds with regard the the RF-connector comparison.

I can't think of many more recent data connectors that are designed for secure fastening: today's fashion in the consumer market is for hot-plugable USB/HDMI/SATA connectors, but I'm not as up-to-date with usage in industrial environments. What has superseded screw-retained D-sub connectors?
 
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asylumxl

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I suppose you have a point there, but there other types of data shoved through d-subminiature ports. And I think my point still holds with regard the the RF-connector comparison.

I can't think of many more recent data connectors that are designed for secure fastening: today's fashion in the consumer market is for hot-plugable USB/HDMI/SATA connectors, but I'm not as up-to-date with usage in industrial environments. What has superseded screw-retained D-sub connectors?

There are screw retained USB, though they're not particularly widespread.

Having said that, there are industrial-standard RJ45-style connectors which are rugged and lockable. One would have thought a standard such Ethernet and these connectors would have been ideal for the application.

I think the reality probably is that many of the older products they produce use RS232 and they'd rather stick with the old technology than invest money modernising the design.
 

najaB

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Having said that, there are industrial-standard RJ45-style connectors which are rugged and lockable. One would have thought a standard such Ethernet and these connectors would have been ideal for the application.
Not if you need to connect nine or more circuits at the same time...
 

najaB

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It's not like a networking standard is designed to connect multiple devices.
True. But a RG45 connector only has eight pads. If you've got nine circuits that need to be connected simultaneously then you're out of luck.
 

najaB

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If only people could make some kind of hub or switcher, that could send data to the right place...
Or, instead of adding complexity they could use a connector with more than eight pins. Now, if only such a connector existed...
 

Nippy

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To clear up the ATP restriction:

It's a General Instruction in the Western Sectional Appendix; the limit is 110 not 100 (albeit I believe it was raised recently); it does NOT apply between Reading and Didcot and is worded thus:

"TRAINS NOT FITTED WITH AUTOMATIC TRAIN PROTECTION (ATP) - MAXIMUM PERMITTED SPEED

Trains not fitted with ATP may travel at permissible speeds between Reading West Junction and Didcot East Junction on the main lines. Over all other sections of line shewn in Table A of this Sectional Appendix as being ATP fitted, the maximum speed for all trains not fitted with ATP must not exceed 110mph at any point.

This restriction is due to design limits of TPWS lineside equipment for trains fitted only with that system."

Sectional Appendix Supp32 - 03/09/16; Module WR1; Page 79 for those that have Up-to-date access.

Thanks for that, I hadn't realised they were allowed at 125 on the MLs between Reading and Didcot. In my defence, I'm on the London desks though so don't sign that side!
 

JN114

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Many thanks for clarifying.
So 110mph TPWS EMUs are OK Paddington-Didcot (or eventually on rugby specials to Cardiff!).

Correct. No comment on the last part :P
--- old post above --- --- new post below ---
Thanks for that, I hadn't realised they were allowed at 125 on the MLs between Reading and Didcot. In my defence, I'm on the London desks though so don't sign that side!

Yeah no worries Nippy; appreciate you link 1 boys probably don't need to know!
 

Dave1987

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Ta. They're comparable with a Class 185, which are the very definition of lardy!

The interior looks horrific, too - but we knew that already.

Reading Ian Walmsley' article in December Modern Railways goes a long way to explaining where the massive overspend on the overheads comes from as well. The overheads are having to be massively over engineered to cope with two pantographs being in contact at such high speeds
--- old post above --- --- new post below ---
But their acceleration is far greater than that of an HST on diesel or electric...

Not on diesel it won't be at higher speeds, will take them longer than a HST to get up to 100 on diesel power. Precisely why some journeys will be slower when IEPs start in service. Been told by someone I know who is loosely involved that the powers that be are trusting the shiny new trains will appease the public on the longer journey times. All press events on these are being very very carefully choreographed, and they still haven't released the figures for how much the extra engines for the fleet being completely bi-mode on GW will cost. I suspect the figures are very embarrassing.
 
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w1bbl3

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I can't think of many more recent data connectors that are designed for secure fastening: today's fashion in the consumer market is for hot-plugable USB/HDMI/SATA connectors, but I'm not as up-to-date with usage in industrial environments. What has superseded screw-retained D-sub connectors?

The industrial stuff we've got for large scale process control is all CANbus based in terms of signalling with various different quasi propitiatory latched connectors coming off the instrumentation, actuators and units depending on the exact application. However at the controller cabinets its mostly DE-9 :p. If it isn't broke no need to fix it.

The controller cabinets our process kit uses do not look that dissimilar to the MERMEC units in terms of being designed as a robust chassis and backplane with a series of field replaceable modules providing functionality and input/output ports.

Miniaturisation in not a specification item for this kind of kit really vs reliability, field replacement and interchangeability. Remember this sort of stuff will have a 20+ year supported life.
The microcontrollers are all TI, NXP, Broadcom, ADI, Infineon, nextchip and probably quite old in technology terms. CPU's are equally old we're not talking 64 bit quad core multi GHz things here but single core low MHz 16 bit / 32 bit designs with the CPU core likely from the early 90's. The software is the clever and modern bit really.
 

najaB

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If only people could make some kind of hub or switcher, that could send data to the right place...
Someone pointed out a flaw with the idea of using a hub/switcher that allows a single cable to carry multiple signals. What was that flaw again?
And then when one cable fails, the whole lot fails. Mmm, good design!
Oh yeah, that was it. :p Added complexity and still has the same flaw as using a nice fat multicore signal cable and DB connector.
 

asylumxl

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The microcontrollers are all TI, NXP, Broadcom, ADI, Infineon, nextchip and probably quite old in technology terms. CPU's are equally old we're not talking 64 bit quad core multi GHz things here but single core low MHz 16 bit / 32 bit designs with the CPU core likely from the early 90's. The software is the clever and modern bit really.

Motorola 68000? [emoji14]
 
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But it's not new technology is it? The RF connector is positively prehistoric. As for the RS232 DB25 connector, it's seriously outdated.

so what wihiz bang connector do you suggest for RF then ?

given that all kindso f radio kit , even those which are entirely software defined still uses co axial to connect the radio to the antennae ?
--- old post above --- --- new post below ---
In the same way anything can be. Otherwise we'd all still be using SCART for everything with a screen.

Scart of course being possibly the worst example to use in this debate

Scart is big, fragile, insecure, designed for analogue and French - which makes it ripe for replacement,

however the various co axial aerial, satellite and cable wall box to cable device co axs are still alive and well ... as a BNCs and the like ...
 

asylumxl

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so what wihiz bang connector do you suggest for RF then ?

given that all kindso f radio kit , even those which are entirely software defined still uses co axial to connect the radio to the antennae ?
--- old post above --- --- new post below ---


Scart of course being possibly the worst example to use in this debate

Scart is big, fragile, insecure, designed for analogue and French - which makes it ripe for replacement,

however the various co axial aerial, satellite and cable wall box to cable device co axs are still alive and well ... as a BNCs and the like ...
Yawn. Totally missing the point. The point was it's hardly new technology contained within the EVC. As always with embedded systems, it's old and stable.
 
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