The London Underground, which uses a four rail DC system, solves the lack of power problem by distributing drive bogies through the train. This also helps avoid power loss when crossing points. Anyone who has travelled on the tube will have noticed the large copper cables used to distribute the power to the rails, a train pulling out of a station easily draws over 3,000A which will cause noticeable losses along a steel rail.

Hopefully developments towards short range battery electric or hydrogen fuel cell trains will help to plug the gap on the shorter lines. Electric buses are already a marvel for public transportation. The future is only going to get better

Will the radius ever vary along the curve -- increasing or decreasing?

Lets hope that the residents in Bath objections to electric trains can be overcome if the wires are ever going to reach Bristol. They claimed that the overhead equipment was too unsightly and would ruin their view. Only in the UK can nimbies sabotage a major rail upgrade and they were glad when it was paused by the government due to increasing costs. That is another reason why electrification has stalled in the UK as we have lost the expertise to do such upgrades. BR used to have it and would have done the whole job on time and within budget. Now we are reliant on private tenders who submit an unrealistically low budget to win the contract. It is only when the work starts that the true cost becomes known leading to cuts due to political interference. Lets hope that if the new government find that they are able to start upgrade works again - which is unknown given the state of the public finances that they have inherited - that the work can be done fully again.

If you want to get the feel of how Hallade works, forget excel to start with, do it the old fashioned way with a pencil and an eraser (good luck finding proper Hallade paper though). See how the slues build up as you do the maths. To be fair, I sat in a classroom for two weeks being taught Hallade by (sadly no longer with us) Howard Finch and it is a very big subject to fit in to a short KZbin video but a good intro to the principle would be the old-school Chargehand's "averaging" method for removing localised alignment faults. Take three versine readings with the middle one being on the fault, work out what the average versine is of the three readings and slue the track to that versine on all three. It's not going to give you perfect alignment but for a localised fault it will improve things a bit.

also with the third rail is if a item made of metal get blown on the track and it touches the third rail and live rail it causes them get welded on the track resulting in trains getting stuck unable to move (if the track is not a type allow trains to run both directions

Less visual pollution on commuter lines. While ohle is better for high speed services

it's harder to get electrocuted when the trains have a pantograph

Chicago sees more variety of weather than most major cities. We’ve seen temperatures from below 0F/-18C to over 100F/38C. And snow and ice so bad, switches near the main stations have permanent natural gas pipes that provide open flames in the winter to keep the switches working. Even so, there is a mix of electric power supply. The ‘L’ subway system primarily consists of third-rail with a short section (Yellow line) with both. The L tracks are famously overhead in the Loop but are also underground and at street level (some far ends). The Metra Electric/South Shore train line uses overhead lines (and until recently, had a street-running section). And the many other passenger and freight lines use diesel/electric engines.

The German S-Bahn third rail system is technically superior to the British system. The third rail is covered and the current is collected from underneath the third rail. This means there is less danger of electrocution and fewer problems with snow and ice. In Britain this variant is used on the DLR.

I have for long time wondered about low frequency AC power for trains. I heard its much cheaper to produce big motors for low frequency AC than power grid frequency. Also there are frequency converters for modern units of today.

Brilliant analysis and commentary 👏🏿. Just subscribed and 👍🏿. Please tell us someone has served time in prison for this which is absolutely corporate killing.

Absolutely brilliant and thank you for the education 👍🏿.

the heat is not a big deal for overhead lines cz there is a system which manage the wiers elasticity

Brilliant explanation, thank you. Subscribed.

Fortunately the world isn’t moving away from oil. The most practical useful and portable fuel out there. 93% of all cars bought are still ICEs. But why let facts get in the way of a good video.

As someone who lives on Long Island, New York, United States, I am familiar with the strange marriage of both systems and unelectrified rails on the "Long Island Railroad." The line at the western most point is used by both Amtrack (overhead) and the Long Island Railroad (third rail) mostly because there is a yard on Long Island for Amtrack, but there is a rumor about a possible tunnel and extension of the Amtrack line through one of the main lines of the LIRR, meaning a significant portion of the line will have both third rail and overhead at the same time. Then we have many extensions of the line without any electrification (not to mention that the freight line is diesel electric, even when they are running on the lines with the third rail).

8:12 Funny how he decides to move his camera when filmimg under the moving train.

On the contrary, lower voltage DC third rail does not need a transformer, while higher voltage AC catenary wire system (like 25kV AC) requires stepdown transformer on the train.

Diesals being much heavier then electric trains have a greater tractive effort, and since most of the electric trains are run in thermal power plants (coal) they are much more polluting indirectly then diesal trains as diesal is lesser polluting, and also on steep gradients electric trains fail to start heavy loads where as diesal trains can easily pick up on such terrain

Love your channel. Cheers from the U.S.A.

around NYC they have some trains that can run overhead and third rail as well as diesel locomotives that can run diesel or third. Dual Power diesels for example run up the Danbury branch of the New Haven line as the branch has no electrification but you also cannot run a diesel into Grand Central. So the locomotive cuts the engine and runs on the third, The Overhead and third trainsets are because the NH line shares most of its track with the NE corridor which is overhead, but the Metro North lines into NYC are all third rail.

The New Haven railroad was compelled to use both third rail and catenary. This is described in book “The Northeast Corridor” by David Alff. books.google.com/books/about/The_Northeast_Corridor.html?id=75LnEAAAQBAJ In the early 1900’s the state of Connecticut made third rail illegal. The New Haven locomotives used 11k catenary on their property, then switched to third rail for using Grand Central station.

Who says the world is moving away from carbon based fuels? China certainly isn't, they are building new carbon based power plants like crazy AND green crap to make the West complacent.

Great Video! I am nit-picking but for your information ALC stands for Automatischer Leit Computer. I've heard many variations using lifting/lining and yours is good too, however, when translated from German it means automatic guiding computer (AGC) as it is needed to guide the machine in transitions and curves. Sorry to be a nerd! 🙂

7:23 cons "Longer geometry issues can be an issue" Something feels wrong about this sentence

I live near Toronto, Ontario. At the moment, a new LRT line is being installed right down the street in front of my condo. They are going with a pantograph system and will soon be installing the wires. In Toronto, the subway system uses 3rd rail, but the streetcars recently switched from trolley pole to pantograph. The new LRT lines in Toronto will also use pantograph.

Nice explainer!!! As a novice train enthusiast, I'm happy to learn this!

Nice explainer!

Very excellent explanation for a novice rail enthusiast like me!!

can you pls make a video on SWITCH and FROG on tracks

It amazes me that there is not the ability to have the live sections come alive as a train approaches each section. Surely that could be built into the signalling system so that as a train approaches the end of one section then the next section of line becomes energised. I know that this would cost more to set up, but if live third rail or live OLE was not energised until just before the train gets to that section, then anytime a train is not in that section, the system could isolate that section so that the risk of electrocution, either by third rail or OLE is negated to quite a degree. Any views please anyone. Serious question which I am interested in.. Thanks.

Not sure where you get the idea that high voltages obviate the need for transformers - the traction motors in a locomotive draw a lower voltage than the majority of overhead supplies. I am pleased that at no point have you referred to catenary, only overhead line equipment (OLE). Most videos bang on about trains drawing their power from the catenary not realizing that their error.

It should also be noted that with OHLE, because it is typically run at higher voltage, it is incredibly dangerous to work or be near active overhead lines. E.g. 25kV AC ohle (what is used in the UK) can jump out to someone up to 6 feet away from the cable itself.

We Need it On Vline In Australia Also in Melbourne Has A Metro Rail system Southern Cross is The Terminus of Vline Services !! AND metro Services! Metro Tunnel will open With 5 New Stations in Melbourne! Two Stations Will Connect Flinders Street Station And Melbourne Central Station Will edit this

Not sure if its still running , but I once travelled on a Train from the Bedford area to Brighton, the first part of the journey was powered from above via a pantograph, then somewhere on the line round west London the train stopped for a couple of minute , the Pantograph was retracted and we continued using power from the third rail! A most interesting ride.

Great video ! I’d be curious to see a video on ballastless track found in china and see how it holds up to ballast

I like counting dropped joints.

A big thumbs up from me in recognition of the clarity of explanation in all your videos and for the consistently top-notch presentation. Add in the animations prevalent throughout this video and my mind is left boggling at the sheer amount of effort and time that goes in to each and every PWay Engineer video. Thank you!

Pretty much spot on, just one thing you came close to but didn't mention. The frequency of the vibration of the tines also causes the ballast to act as if it were a fluid. This enables it to flow in to voids beneath the sleeper beyond where the tines could just push it.

Spent many a day on the kango, packing ballast on routine maintenance and after working on a procession at night. And while working at one P'way, they needed a site warden on a tamper. That was the easiest two weeks I've had, as they told me to get my head down (easier said than done with the motion of the tamper once she got going) or help myself to a coffee. I was going to mention, the tamper I worked on, when she got to the site, she would make a recording run and then do the tamping run. When we worked on a weekend relay, we would remove some ballast from the sleeper top, so the operator of the tamper could see their location.

thnks

Thanks for a clear and not overly detailed explanation.

Good morning. Great video. Well made. The tamping of track has come a long way from back in the day. Back in the day, a track jack and a Dimond end tamping bar. I started off with a 1959 Jackson maintainer machine. Then we got a new plasser from amtrk it was not too bad, but the machine ran on the piano wire system. The machine we have now is a switch Tamper, where we still have to set track Jack's. When we get contacter in. They have the Mark lll Tamper, Mark IV and the Mark V. I am impressed how good of the job they do. They new machine started with the delta system and now the Jupiter system. The only drawback is when the machine starts to break down and the operator can't fix it. Back to the 1959 Jackson maintainers. Great video. From cross the pond to the west to South Central Pa.

Both New York City and London have multiple lines of third rail electric commuter trains that reach far out into the countryside, with level crossings, unprotected access and all the potential danger it implies.

So what was it about the Class 373 Eurostar sets that meant they had to pass at very low speeds when crossing switches at certain stations during their use on the ECML? Was that to do with end-throw?

There is a trend worldwide for some new urban metro systems, which would normally be third rail, to install overhead wires.

Overhead wires offer the most safety and have lower maintenance costs. Also it’s almost impossible to run any sort of high speed rail with 3rd rails which is why it’s usually limited to subways.

Alston announced a 100mph 90 mile range battery train. They are here. The batteries are only getting better. This sort of range is good for say a HS2 hybrid serving Chester, on battery for the last 30 miles as wires cannot be fitted as the bridges are too low. Trains will also get lighter to improve efficiencies. I can see *de-electrification* on many passenger routes especially on 3rd rail. Ellesmere Port . For example on Merseyrail, the dangerous 3rd rail can be ripped up from Spital station to Chester and Ellesmere Port stations when the Warrington service extended from Ellesmere Port comes online using the battery hybrid Class 777s which can charge from the 3rd rail.