Indian Railways Thread (Dec 2015)

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Aditya_V
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Re: Indian Railways Thread (Dec 2015)

Postby Aditya_V » 15 May 2019 15:36

I for one have 2 reasons why we must have atleast 1000-1500 Diesel engines.
1. Rail launched agni series, cant have overhead electric lines.
2. In times of war Diesel engines can operate far more indeoendantly than ensuring electric supply to strategic railways.

We must have the contingency plans in place.

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Re: Indian Railways Thread (Dec 2015)

Postby nandakumar » 15 May 2019 16:00

chetak wrote:
arvin wrote:Piyush goyal did try to convince GE to scrap the diesel project and manufacture something else. But they did not budge. Goyal was putting a brave face when he justified the strategic thing but within him he knew, this wasnt fitting in larger scheme of things.
I think CAG also had a lense on the project and quoted a figure of 17000 cr as total cost including land acq.
Blame must squarely fall on babus in rail bhavan and heads must roll for this collosal waste of money.
It looks funny , The contract was signed with suresh prabhu as rail mantri in 2015 and within 2 years after goyal takes over he questions the need for the diesels. Clearly babus manning the files did not have the vision to advise prabhu against it.


i think that going to full electrification in the short to medium term is something of a mission impossible sort of exercise. It is nice to have such an ambitious goal but we lack the resources to do this given the numerous other sectors that are competing hard for a slice of the limited financial pie and the other national goals that may take precedence.

so we will bash on with a mixture of electric and diesel and gradually replace the diesels as and when they warrant it and that's not such a bad thing at all.

what happens if the next govt has a different take on things. International players have very deep pockets and will sway policy to suit themselves and look to offload older products with some lipstick and new facepaint

GE is obviously playing the long game and their bird in hand is worth very good money.

everyone abroad, including many in India, especially the middleman types from lootyens dilli have suddenly discovered the very obvious advantages of having a weak govt at the center.

Also there is the factor of economics. The investment in transmission network to sustain railway operations is not justified if track is not intensely used is not justified. In a network as large as India's all sections cannot be uniformly used. May be an odd spur taking off from a trunk route can be electrified even though traffic volume does not warrant it for the reason that the logistics of keeping a dedicated diesel loco shed just for a 40 km spur may be too much of a hassle. But otherwise a judicious blend of electric and diesel is the way to go.

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Re: Indian Railways Thread (Dec 2015)

Postby arvin » 15 May 2019 22:10

https://www.dailypioneer.com/2019/colum ... lemma.html

Good piece on perils of fully electrified lines.
Entire load will shift to coal plants which are more polluting than diesel. A central power source presents a danger in which if taken down via say hacking will bring to a halt all lines dependant on it. Venezuela recently saw unexplained power outages (US trying to install guaido there). Coal transportation on such a scale itself might choke rail lines.

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Re: Indian Railways Thread (Dec 2015)

Postby Kashi » 16 May 2019 08:55

arvin wrote:https://www.dailypioneer.com/2019/columnists/the-rail-network-dilemma.html

Good piece on perils of fully electrified lines.
Entire load will shift to coal plants which are more polluting than diesel. A central power source presents a danger in which if taken down via say hacking will bring to a halt all lines dependant on it. Venezuela recently saw unexplained power outages (US trying to install guaido there). Coal transportation on such a scale itself might choke rail lines.


Coal transportation will completely move to DFC. But yes, the push for full electrification needs to be preceded by proper planning.

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Re: Indian Railways Thread (Dec 2015)

Postby ritesh » 16 May 2019 09:21

My inlaws took journey in duronto this week. Train was fairly on time, cleaning was ok, coach was lhb. However, food which was inbuilt into fares was awful. Even the hot beverages were machine made and simply not upto mark.

When i took journey in the prevoius week in a superfast train, food and beverages were nice though costing extra and provided by local vendors.

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Re: Indian Railways Thread (Dec 2015)

Postby Singha » 16 May 2019 16:18

Aditya_V wrote:I for one have 2 reasons why we must have atleast 1000-1500 Diesel engines.
1. Rail launched agni series, cant have overhead electric lines.
2. In times of war Diesel engines can operate far more indeoendantly than ensuring electric supply to strategic railways.

We must have the contingency plans in place.


in that sense, even if using diesel engines, doesnt the presence of overhead wires render and growing vast stretches of IR unusable for rail launch Agnis. not that I am complaining, just saying that rail launch may no more be realistic for us.

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Re: Indian Railways Thread (Dec 2015)

Postby chetak » 16 May 2019 16:31

ritesh wrote:My inlaws took journey in duronto this week. Train was fairly on time, cleaning was ok, coach was lhb. However, food which was inbuilt into fares was awful. Even the hot beverages were machine made and simply not upto mark.

When i took journey in the prevoius week in a superfast train, food and beverages were nice though costing extra and provided by local vendors.


the railway guys make a killing on catering and hence the suppliers have only the one defence of reducing the quality.

passengers/customers are mostly transient and very few travel regularly for maybe work purposes.

most may not even bother to complain officially.

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Re: Indian Railways Thread (Dec 2015)

Postby Kashi » 16 May 2019 17:47

Singha wrote:in that sense, even if using diesel engines, doesnt the presence of overhead wires render and growing vast stretches of IR unusable for rail launch Agnis. not that I am complaining, just saying that rail launch may no more be realistic for us.


I think if we are in a situation that we'll deploy rail-launch Agnis, OHT wires will be the least of our problems.
.

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Re: Indian Railways Thread (Dec 2015)

Postby Supratik » 16 May 2019 17:54

Diesel is needed for back-up and niche areas but 1000 nos may be a tad high.

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Re: Indian Railways Thread (Dec 2015)

Postby Aditya_V » 18 May 2019 12:59

Singha wrote:
Aditya_V wrote:I for one have 2 reasons why we must have atleast 1000-1500 Diesel engines.
1. Rail launched agni series, cant have overhead electric lines.
2. In times of war Diesel engines can operate far more indeoendantly than ensuring electric supply to strategic railways.

We must have the contingency plans in place.


in that sense, even if using diesel engines, doesnt the presence of overhead wires render and growing vast stretches of IR unusable for rail launch Agnis. not that I am complaining, just saying that rail launch may no more be realistic for us.


Rail launch can be a back up , better to have 75% road mobile and 25% rail launched onces, Railway tunnels can be good places to hide wagons, and faster transportation of heavy missiles.

Yes many streches with electric lines cannot be used for launch, no problem for transport.

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Re: Indian Railways Thread (Dec 2015)

Postby mridulmm » 19 May 2019 07:37

Piyush Goyal Office
@PiyushGoyalOffc
Another Make in India Success Story: The indigenously made Vande Bharat Express' second rake is ready and is off to New Delhi from Integral Coach Factory in Chennai, Tamil Nadu.

https://twitter.com/PiyushGoyalOffc/status/1129771378222206977

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Re: Indian Railways Thread (Dec 2015)

Postby vsunder » 19 May 2019 08:00

Sorry I do not understand the logic why if there is OHE equipment one cannot then launch missiles? why? The missile carrying train will of course be hauled by diesel in case there is loss of power to the overhead lines by enemy action. The trains will be housed in specialized sidings as the US does, and the missile can be launched from the sidings if needed. The US trains have this facility. At most 50 such missiles are dispersed on trains with 2 missiles per train in the US.

One can do one of two things. 1. Go to the nearest siding and there are plenty of them even on OHE lines in India where there is no OHE equipment above and launch from there. Such sidings are seen at many places with a warning to the e-loco pilot not to proceed beyond point Z, or else the loco dies.

2. Go to a neutral section and launch from there. Neutral sections are 35-40km apart and by design away from a level crossing and on level ground. Neutral sections are 50m to a 100 m long enough to place two wagons and launch at a slightly depressed angle to miss the wires which are dead anyhow as it is a neutral zone.

What is a neutral zone?: Power is sent from a power plant at 132,000volts in 3 phases with wires A, B,C. At a place Singaramapete, wires A,B are tapped by the TSS(traction sub station) and stepped down to 25,000 V and fed to the OHE. 40 km away at another TSS at Peepalganj, wires B,C are tapped and fed to the OHE at 25,000 Volts, and then 40km away at Buddhunagar wires A,C are tapped and fed to the OHE at 25,000 V. Between these sections a neutral zone has to be inserted or else the different phases will short each other out. The neutral zone is not electrified and the momentum of the loco is supposed to carry it from one sector to another over the dead zone. You might notice this by a slight dimming of the lights etc as the loco pilot opens the fuses and then closes them when in the new zone. The pilot gets a warning from signs placed trackside, that one is approaching a dead zone and fuses have to be opened. Another reason that at higher speeds one needs in cab signalling.

The idea is probabilistically the same number of trains are in each zone and thus the load on the central power plant is the same across the three phases if tapping is distributed as detailed above. This entails the loco is being supplied with single phase 25,000 V current. DFC has a better scheme which is not single phase, but this is more involved. I believe that such a better scheme has been tried on IR between Bina and Katni.

There are various guidelines by RDSO of the insulating material and length of the neutral zone, but the minimum length is 40m and the max about 100m. But 1. still seems the better option.

PS: On another note what was the ruckus about Modi and radar. Have not people seen a rainbow in the sky and asked what was it about? Or why the sky is blue?
The water molecules in the air scatter light and different frequencies scatter differently. Higher frequencies scatter more and so we see the uniform blue of the sky. Radio waves are electromagnetic waves like light so it must do that too.

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Re: Indian Railways Thread (Dec 2015)

Postby vsunder » 20 May 2019 07:50

SWR is getting its first electric loco shed with the track km of electrification on SWR increasing substantially. The venerable Krishnarajapuram (KJR) diesel loco shed outside Bangalore which was established in 1983 will be converted to an electric loco shed by Dec 2019 or Jan 2020. Hubbali (HQ of SWR) will remain as the only other diesel loco shed in Karnataka. However, electrification around Hubbali is also fast progressing with lines to Dharwad, and on to Goa to the west, to Gadag and Hosapete to the east and south east to Bangalore being electrified.

http://epaper.newindianexpress.com/c/39465335

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Re: Indian Railways Thread (Dec 2015)

Postby hnair » 20 May 2019 08:31

vsunder, great info as usual about netural zones. I was indeed wondering how a rail based system can launch. A question: wouldn't neutral zones also have the wires? Or is that 100 meters are free of caternary wires?

But other than heavily loaded trunk routes, fact remains that we will have to depend on diesels for most parts of country! Wonder what made the minister go back on the GE project? There is no tech advancement like battery or anything remotely challenging a diesel chugging along a lonely line. Maybe something else?

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Re: Indian Railways Thread (Dec 2015)

Postby vsunder » 20 May 2019 08:56

Neutral zones have a catenary wire just so that the pantograph is in contact with something, or else there will be an additional problem when the pantograph again makes contact with the live section. RDSO specs deal with the type of insulators to shield the neutral zone from the live ends (at either ends of the neutral section). Neutral zones are selected to be away from LC's and on level ground or going downhill, so that the problem of a loco getting stuck in the neutral zone is minimized, it is known to have happened but rarely. I do not think the presence of wires will impede a missile launch if done at an angle. In any case when India gets to rail mobile missiles, a simple mechanism of either shooting the missile at an angle from the rail car or a mechanism of allowing wires to disconnect and fall from the OHE equipment by pulling a lever attached to a traction pole, something as simple as that will be worked out, preferably the neutral zone wires fall down. I have seen one video though on youtube of a train that had sealed windows and military support crew in additional coaches that looked suspiciously like a missile transport. The videographer had shot the video on the Bhopal-Jhansi section which of course is an important main line which is electrified.

The symbol that alerts a eloco pilot that he is approaching a neutral section is a board with a diamond with say 500m written on it. This is usually affixed to a traction pole. Then at the neutral section one has a board that has two vertical lines with a gap between them and a horizontal line in the gap. Something like this:

|
_
|

Lastly comes a board with three vertical lines with gaps between them----neutral section passed.

|

|

|


Since I am at it and we have had some discussion about this: OHE equipment wire esp. is tensioned and you might see a bunch of weights like what you see in the weight machine at the gym, attached to the OHE wire. This weight is anywhere from 8-20 Newtons. One knows from elementary mechanics that the wave speed of disturbances along a string/wire is proportional to T^{1/2}, where T is the tension in the wire. So applying more tension in the wire makes the speed that sound waves travel along the wire faster. The goal is to prevent transverse waves along the wire that would cause the wire to break and in particular the speed of sound > speed of the train. The analogy is that you do not want the aircraft to approach the sound barrier. Here you can control the speed of "sound" by making it very high by tensioning the wire and so the sound speed is more than the train speed. Ditto for HSR. The tensioning is done every 2km or so. That explains the gym weight equipment hanging trackside from OHE poles.

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Re: Indian Railways Thread (Dec 2015)

Postby Prasad » 20 May 2019 10:40

How does rail launch work when overhead wires are at 5-6m height and missiles are 10m+ long? Even inclined, stuff will get roasted.

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Re: Indian Railways Thread (Dec 2015)

Postby Kashi » 20 May 2019 10:48

The wires can be pulled out, dismantled, poles uprooted in the case of such emergencies.

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Re: Indian Railways Thread (Dec 2015)

Postby arshyam » 20 May 2019 11:00

vsunder wrote:and the missile can be launched from the sidings if needed

This is the simplest thing to do. Also, these are ubiquitous and generally innocent looking, so cannot be distinguished by the enemy as a military facility for targeting. Simply ride in a diesel hauled rake one day, open the hatch, and fire! Can be done from any marshalling yard too...

vsunder wrote:Neutral zones have a catenary wire just so that the pantograph is in contact with something, or else there will be an additional problem when the pantograph again makes contact with the live section.

I believe the pantograph is tensed to push upwards against the catenary so it maintains continuous contact. If that's correct, without an OHE, the panto will be pushed further up and get entangled with the next wired section, unless it is drawn down during the neutral section and pushed again after passing the end sign.

Anyway, all this is moot since the wire is continuous, the power supply only isn't.

vsunder wrote:SWR is getting its first electric loco shed with the track km of electrification on SWR increasing substantially. The venerable Krishnarajapuram (KJR) diesel loco shed outside Bangalore which was established in 1983 will be converted to an electric loco shed by Dec 2019 or Jan 2020. Hubbali (HQ of SWR) will remain as the only other diesel loco shed in Karnataka. However, electrification around Hubbali is also fast progressing with lines to Dharwad, and on to Goa to the west, to Gadag and Hosapete to the east and south east to Bangalore being electrified.

http://epaper.newindianexpress.com/c/39465335

Work to commission the Guntakal (GTL) electric loco shed is apace and should be done soon. That will take care of the Guntakal-Bellary-Hospete-Huballi route. But I think the nearby Gooty shed should also be made electric soon, as the demand is going to shoot up significantly. Apart from the Chennai-Mumbai trunk line, all the branches to Kurnool-Kacheguda, Nandyal-Guntur, Dharmavaram-Penkonda-BLR and of course the above-mentioned Bellary-Hospete routes are also coming under wires, perhaps within a year's time. Just a Guntakal in SCR and AJJ in SR cannot handle the load. Heck, even Huballi (UBL) will need to start homing electrics at some point.

This section is freight-heavy to boot, so there's even more demand for goods locos. That's probably why they are pulling off the older (diesel) WDG-4s out of Huballi and converting them into (electric) WAG-11 twinsets. Hopefully these will end up either at GTL or UBL to replace the lost capacity.

Supratik wrote:Diesel is needed for back-up and niche areas but 1000 nos may be a tad high.

It translates into 60 locos per zone. I am sure there is enough work for them on the mainlines, not to mention the strategic aspects of it. My guess is that out of the the total 13-15000 locos needed on IR, we will get rid of all the older diesels (decommission, rebuild as electric, derate for shunting) and keep only these 1000 locos operational for mainline duties. Diesel costs would anyway be significantly down from the current 6000(?) diesel locos in service, and these locos being newer will also be more fuel efficient, keeping the costs low. I am sure as a country we can afford to keep that many diesels as a backup. Also in the long run, we don't want to end up with too few diesels, as it would lead to the bespoke spare parts issue our military constantly faces due to low order runs. Keeping that in mind, 1000 is a good number of have and keeping making in India. Not to mention continuing to maintain a base for diesel engine tech in the country that we can tap into if the need arises again in the future.

Of course, the next govt may come and reverse this policy completely. Or maybe we'll find customers to export these locos to: being originally designed for SG, regauging these locos for export should be possible - GOC workshop at Tiruchi has done quite a bit in that space.

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Re: Indian Railways Thread (Dec 2015)

Postby arvin » 20 May 2019 15:41

Assuming 5k+ diesels will be converted to electric , adding 800+ from alsthom and existing 5k+ electrics, GE's 1000 diesel will probably constitute 10% of rail transport mix. IMO thats a sweet spot to have considering current rail diesel bill of 12000 cr will become approx 2000cr or less if linearly interpolated.
Recent palm oil deal with malayasia may also be for bio diesel production to further reduce import bill.

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Re: Indian Railways Thread (Dec 2015)

Postby vsunder » 21 May 2019 08:12

Approaching a neutral section when the pilot sees the diamond sign at 500m, he notches down to 0, and shuts down all blowers that keep the machinery cool and shuts down any power electronics that may get damaged by arcing and sudden jumps of voltage. Now essentially the loco is coasting. The pilot has about 15 second before entering the neutral section for which a warning is given by a sign that I explained earlier. In about 10 seconds the pilot opens all fuses (DJ type main circuit breakers) and now one is in the neutral section. Once the neutral section is crossed, the fuses are closed first and the pilot then notches up and turns the blowers and electronics on and maintains speed.

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Re: Indian Railways Thread (Dec 2015)

Postby arshyam » 21 May 2019 10:38

^^ This is one of the clearest videos I know of where the loco navigates the neutral section.



It's an old video of a WAP-3 (now extinct) hauling the Bhopal Shatabdi out of Delhi. In the video, we can hear the assistant LP calling out the signals as per procedure: advance green, 500 board, 250m board, open DJ, close DJ, and a final (unclear) command, post which the whine of the compressors is heard as power is restored.

The 500m and 250m boards are the advance warning signals to the LPs that a neutral section is approaching. DJ is the main circuit breaker on the older WAM-x and WAG-1-7 tap changer type locos. I don't know why it is called the DJ though (vsunder sir may know?). The newer 3-phase locos should have a similar procedure, and perhaps simpler ones too. Not aware of that.

For the more technically inclined, this schematic on IRFCA explains how the electric traction grid is built.

https://www.irfca.org/docs/traction-fee ... matic.html
Image

This FAQ explains how the neutral zones work: https://www.irfca.org/faq/faq-elec.html#dead

The signs for the neutral sections look like this: https://www.irfca.org/faq/faq-signal5.html (look at the Catenary Signs section)

Image
Image

Interestingly, neutral zones were not only used to isolate different phases of AC power, but were also used to isolate the DC traction area in Mumbai from the AC traction area in the rest of the country (practically speaking, the line toward Surat on the WR line, and Igatpuri on CR). IIRC, a point beyond Virar when going out of Mumbai was the point where DC ended and AC traction started. Locos would form a conceptually similar procedure when crossing this stretch, but with a slight difference. Unlike the WAM/WAP/WAG series, they would be dual-power locos capable of handling both DC and AC power (WCAM and WCAG series). So in this section, they'd turn off the DC traction equipment and lower the DC pantograph when approaching the dead zone, and once in the AC zone, and raise the AC pantograph and turn on the AC traction equipment.

There was a similar zone at Igatpuri station on Mumbai CR's north east line (toward Nasik), but here the operation was different. The train would pull into the platform from Mumbai on DC traction, and the DC loco (or the AC-DC loco) would be detached and sent to a siding, post which the same catenary would be energized with AC power and the AC loco would be brought in to couple itself to the rake and haul the train further. The reverse would happen for trains going toward Mumbai. This was a more cumbersome and time consuming process compared to the system used on WR, but this was done for terrain reasons I think. As vsunder sir said, a neutral zone needs to be on level ground for a sufficient distance in both directions so locos have enough power to coast through without getting stalled. IGP being just after the ghat section perhaps didn't offer this luxury. Also, since CR didn't have a lot of AC-DC locos to begin with, and eventually had only around 70 WCAM-3 locos with its pure DC loco fleet becoming old and dwindling, they were loathe to let these locos go beyond Igatpuri as the demand was high in the Mumbai area itself. But in theory, these could have proceeded beyond IGP on AC power like was done on WR.

The other DC endpoint in CR was at Pune, but the changeover here was very simple, as the change here was to diesels, so OHE type didn't matter at all.

The above constraints were the reason that none of the Mumbai area loco types (WCM-x, WCG-x, WCAM-x, WCAG-x) would venture too far from the home territory as only these locos could handle the traffic within Mumbai. So all trains into Mumbai used to get a compulsory loco change at some point away (Vadodara, Surat, Igatpuri, etc.).

With the entire Mumbai region coming under AC traction now, these changes are now completely done away with. Most (perhaps all by now) AC-DC dual-power locos have been made pure AC locos and are serving out their remaining service life.

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Re: Indian Railways Thread (Dec 2015)

Postby nachiket » 21 May 2019 10:45

Thanks vsunder and arshyam. Some incredible information in the past few posts. Very informative.

Why was the Mumbai area always DC compared to the rest of the country which wasn't? Having grown up there I remember wondering about this even back then, but never got an answer.

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Re: Indian Railways Thread (Dec 2015)

Postby arshyam » 21 May 2019 11:07

Mostly historical reasons - DC traction was in vogue then (1920s and 30s). Even Calcutta and Madras areas started off with 3kV and 1.5kV DC traction only, but were switched to AC in the 50s. This was because IR decided to adopt AC traction for its mainline routes, so it made sense to unify the network on a single system. The involvement of the French railway (SNCF) supplying the initial WAM-1 AC locos probably had a bearing on this. The Bombay area was left as is perhaps due to the much larger network with high traffic even back then (all of Mumbai-Pune/Igatpuri and Mumbai-Surat was electrified by then), and the cost of converting this to AC was deemed too high. Also being newly independent with very scare resources did not justify this conversion.

Again, will defer to vsunder sir on these points.

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Re: Indian Railways Thread (Dec 2015)

Postby Sridhar K » 21 May 2019 16:33

Knew of dead zones in WR/CR but was unaware of dead zones in AC traction though was intrigued by the signs.

Also used to wonder if those WCAMs on CR went beyond Igatpuri.

Thanks for the clarifications. One question though on whether WCAM hauling Rajdhanis hauled the rakes all the way to Delhi or where they changed after Baroda? Used to love the shape of the BHEL built WCAM 2p

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Re: Indian Railways Thread (Dec 2015)

Postby arshyam » 21 May 2019 16:47

^^ All of them changed at Baroda. This was the northernmost station these locos ventured up to.

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Indian Railways Thread (Dec 2015)

Postby Peregrine » 21 May 2019 19:29


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Re: Indian Railways Thread (Dec 2015)

Postby vsunder » 21 May 2019 19:37

@Arshyam: Thanks for posting the video and a clean link to the signs which is far better than I could do. Your schematic of the connections shows clearly the various taps made of the 3-phase current coming from the central power plant. R,Y,B in the schematic refers to Red, Yellow and Blue wires. I called them A,B,C in my original post.

Regarding your questions:

What is DJ? The short answer is circuit breakers are classified by letters depending on their rating and function, B,C,D,K,Z and then there are sub-specifications. Here is a short tutorial on MCCB's (Moulded case circuit breakers)

https://www.gses.com.au/technical-artic ... -breakers/

The section Sizing the MCCB's ^^^ contains a table with the characteristics of each type of circuit breaker B,C,D,K,Z etc. Type DJ's used in locos are a legacy product in the US and unavailable except perhaps refurbished ones. Generally such high performance breakers are not cheap and can cost $2000 or more. Generally homeowners do not pay attention to the circuit breakers, but one should not skimp on this important product and always install a product from a reputable company like Siemens or equivalent company, Schneider electrical has a good reputation too.

The key takeaway in the specs above is that Type D trips at 10-20 times the current rating, the highest in the list. This would be the case say in an electric loco when for example a motor is turned on there will be a momentary very large surge in current and you do not want the breaker to trip for a safe operation.

Regarding the electric networks. As you correctly point out Mumbai got 1500V DC in the 1930's and when I was little the famed "alligator" types did a lot of hauling in that network. Examples of this alligator type and the ones used around Chennai are on display in the National Rail Museum in Chanakyapuri. Kolkata started with 1500V DC in 1957 on the Howrah-Bardhaman(Burdwan) line with electrification barely reaching Bandel. When in the next year the electrification was changed to 25KV AC and then continued with that. The Harbor line in Mumbai remained DC for the longest time as only local trains plied on it, now the entire network is fully AC. The changeover took so long for Mumbai since as you point out changing it would be involved, disruptive and expensive since by the 1950's the network was quite large.

I still remember the days when an e-loco took you from BBVT/CSTM to Igatpuri 1500V DC and then a fully coaled and watered WP steam engine at Igatpuri would be attached to take you to Jhansi and onwards. Even the Delhi-Mumbai CR line via Itarsi was a single line affair.

Crocodile/alligator type e-loco that was common in the Mumbai network and a model at the National Rail museum at Chanakyapuri, New Delhi.


https://en.wikipedia.org/wiki/File:Indi ... e_4502.jpg

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Re: Indian Railways Thread (Dec 2015)

Postby vsunder » 21 May 2019 20:58

Another takeaway from the video posted by Arshyam towards the end is when the ALP calls out double yellow, and soon after advanced Green. That means the loco has to slow down and then allowed to speed up to MPS(maximum permissible speed). The reason is the train is seen passing through a platform line at Okhla outside Delhi. This is the bane of all semi-HSR or fast trains on IR. If you do not have a dedicated through line away from the platforms, trains have to slow down and then speed up. This adds to journey time and it is worse if you get looped when one has to really slow down.

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Re: Indian Railways Thread (Dec 2015)

Postby arshyam » 21 May 2019 22:17

vsunder wrote:@Arshyam: Thanks for posting the video and a clean link to the signs which is far better than I could do. Your schematic of the connections shows clearly the various taps made of the 3-phase current coming from the central power plant. R,Y,B in the schematic refers to Red, Yellow and Blue wires. I called them A,B,C in my original post.

I take no credit beyond having shared these links here :). The credit should go to the kind soul(s) who drew those drawings and made them available to the IRFCA FAQ.

vsunder wrote:Regarding your questions:

What is DJ? The short answer is circuit breakers are classified by letters depending on their rating and function, B,C,D,K,Z and then there are sub-specifications. Here is a short tutorial on MCCB's (Moulded case circuit breakers)

https://www.gses.com.au/technical-artic ... -breakers/

The section Sizing the MCCB's ^^^ contains a table with the characteristics of each type of circuit breaker B,C,D,K,Z etc. Type DJ's used in locos are a legacy product in the US and unavailable except perhaps refurbished ones. Generally such high performance breakers are not cheap and can cost $2000 or more. Generally homeowners do not pay attention to the circuit breakers, but one should not skimp on this important product and always install a product from a reputable company like Siemens or equivalent company, Schneider electrical has a good reputation too.

The key takeaway in the specs above is that Type D trips at 10-20 times the current rating, the highest in the list. This would be the case say in an electric loco when for example a motor is turned on there will be a momentary very large surge in current and you do not want the breaker to trip for a safe operation.

This was very useful, learned something new today...

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Re: Indian Railways Thread (Dec 2015)

Postby vsunder » 21 May 2019 22:47

Another takeaway from the video Arshyam posted. Notice the steering wheel where the loco pilot is manually adjusting the tap and so the amount of current the loco is drawing from the overhead line and so keeping the speed at some maximum permissible. Then also listen carefully to the noisy chitchat, someone asks about "tapping" and the do dah who is giving lots of "gyan" says in Hindi thyristor par ek hi loco trial par chal raha hai. Thyristor control and associated power electronics is the modern way that e-locos draw on power and control the tap and current flowing into the loco. The steering wheel thingie is old fashioned.
Here is a Ma'am explaining it all:

https://www.youtube.com/watch?v=LBb_Qz7J3zA

The thyristor actually can manufacture DC current with control and an invertor in the loco converts the DC back again to AC which is then applied to the driving motors.

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Re: Indian Railways Thread (Dec 2015)

Postby Karthik S » 25 May 2019 07:39

Japan is working on next shinkansen avatar called ALFA-X.
Will take 3 years to complete the tests, JIT for our M-A line. Not sure if we can upgrade from E-5 to this now, will be good to have latest version.

https://en.wikipedia.org/wiki/ALFA-X

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Re: Indian Railways Thread (Dec 2015)

Postby yensoy » 25 May 2019 08:56

vsunder wrote:The thyristor actually can manufacture DC current with control and an invertor in the loco converts the DC back again to AC which is then applied to the driving motors.


Mani Vijay is a legend and his videos are gold. There is no other record visual record of IR at that level of breadth and depth.

This video is very dated. WAP-3 was an experimental loco based on WAP-1, with DC traction motors, so the thyristor was used to create pulse width modulation DC only (to effectively control the voltage with high efficiency).

Current generation locos being manufactured all have AC traction motors with variable frequency drive circuitry that produces AC voltage at the right frequency to drive the AC induction motors. They are miles ahead of DC thyristor technology. They are sensors to measure wheel slip so as to not overdrive the motors and cause uneven wheel & rail wear; they can also function "backwards" to regenerate voltage at 50Hz to return to the grid while braking.

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Re: Indian Railways Thread (Dec 2015)

Postby vsunder » 28 May 2019 18:43

I am also told that the terminology DJ has an origin from the French word disjoncteur which means circuit breaker. So there seems to be two roots for DJ, one is as above D type circuit breaker in a J type frame and this French thingie.

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Re: Indian Railways Thread (Dec 2015)

Postby Ashokk » 28 May 2019 20:10

Prasad wrote:How does rail launch work when overhead wires are at 5-6m height and missiles are 10m+ long? Even inclined, stuff will get roasted.
The russian missile train has a tower-like device which is used to move the overhead cables aside.
Watch from 2:10


Image

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Re: Indian Railways Thread (Dec 2015)

Postby JTull » 29 May 2019 16:40

Does anyone know the status of world's highest bridge which is part of JUSB line on Chenab in J&K? I only have this link

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Re: Indian Railways Thread (Dec 2015)

Postby SBajwa » 29 May 2019 23:24

JTull wrote:Does anyone know the status of world's highest bridge which is part of JUSB line on Chenab in J&K? I only have this link



https://www.financialexpress.com/infras ... s/1484997/

To be completed by end of 2019. Last I heard there was a problem between railways and the contractor. Contractor wanted some n amount of more steel which was not part of the original contract.

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Re: Indian Railways Thread (Dec 2015)

Postby JTull » 30 May 2019 00:39

Critical projects being delayed by such silly issues! Either the Konkan Railway guys have misspecified the requirements or the guy who took ghoos has moved on. Now the new guy wants contractor to pay up or absorb losses.

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Re: Indian Railways Thread (Dec 2015)

Postby Pratyush » 31 May 2019 10:25

Ashokk wrote:
Prasad wrote:How does rail launch work when overhead wires are at 5-6m height and missiles are 10m+ long? Even inclined, stuff will get roasted.
The russian missile train has a tower-like device which is used to move the overhead cables aside.
Watch from 2:10


Image



I always thought that this was an antenna for a secure communications terminal.

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Re: Indian Railways Thread (Dec 2015)

Postby vsunder » 31 May 2019 15:44

A short video by WR on gauge conversion of Ahmedabad-Udaipur MG line. There is an older video of this line made by a French team of the days of steam. This line underwent CRS inspection between Ahmedabad and Himmatnagar in March 2019. Once the Zawar tunnel is completed near Udaipur, the line will be fast done and help the tribal area this line passes through. In addition this line will help:

1. steel plants as it passes through areas rich in Zinc ores and also potash.

2. It opens an alternative route from Ahmedabad to Delhi in addition to the current route through Marwar and Ajmer.

CRS inspection:

https://www.youtube.com/watch?v=Mb6GnF2d2jg

The WR video. A large number of LC's were eliminated via ROB's and RUB's and also grade modification was made with an alternative alignment so that the line has a lower than the original 1: 150 ruling gradient:

https://www.youtube.com/watch?v=Pcfn3fm ... e=youtu.be

Veiled in Vapour, an old documentary of steam on this very MG line Ahmedabad-Udaipur

https://www.youtube.com/watch?v=bIpekofg6ug

This video above is simply beautiful, a long ago time, I am glad I saw it.
Last edited by vsunder on 31 May 2019 16:06, edited 1 time in total.

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Re: Indian Railways Thread (Dec 2015)

Postby Karthik S » 31 May 2019 15:53

vsunder wrote:A short video by WR on gauge conversion of Ahmedabad-Udaipur MG line. There is an older video of this line made by a French team of the days of steam. This line underwent CRS inspection between Ahmedabad and Himmatnagar in March 2019. Once the Zawar tunnel is completed near Udaipur, the line will be fast done and help the tribal area this line passes through. In addition this line will help:

1. steel plants as it passes through areas rich in Zinc ores and also potash.

2. It opens an alternative route from Ahmedabad to Delhi in addition to the current route through Marwar and Ajmer.

CRS inspection:

https://www.youtube.com/watch?v=Mb6GnF2d2jg

The WR video. A large number of LC's were eliminated via ROB's and RUB's and also grade modification was made with an alternative alignment so that the line has a lower than the original 1: 150 ruling gradient:

https://www.youtube.com/watch?v=Pcfn3fm ... e=youtu.be

Veiled in Vapour, an old documentary of steam on this very MG line Ahmedabad-Udaipur

https://www.youtube.com/watch?v=bIpekofg6ug


Sir, any updates on Chennai Bangalore HSR project? Germans submitted feasibility study to IR in Nov last year, nothing much after that.


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