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How electric trains work and why they make interesting sounds [video]

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Re: How electric trains work and why they make interesting sounds [video]

#41

Post by the_mitsuhiko »

exabrial wrote: post #38

I do not have perfect pitch (cool party trick), but I can identify all 8 'normal' equal temperament intervals by ear relative to a reference (If you couldn't guess, I play bass, which is a lame party trick). I was in Austria last year, and a bunch of the trains starting from a standstill had a "gradual acceleration" algorithm for their traction motors. As the drive frequency increased, you could hear the drive motor…

Normally it just plays the scale: https://www.youtube.com/watch?v=-SDYdHzT7Qw

But it can be configured to play other tunes. Here is a rare recording of it playing the Austrian anthem: https://www.youtube.com/watch?v=UkdQmDGU9AM (another recording: https://www.facebook.com/unsereOEBB/videos/290883783832057/)

Re: How electric trains work and why they make interesting sounds [video]

#42

Post by rootusrootus »

gambiting wrote: post #32
rootusrootus wrote: post #25

Earlier quoted context omitted.

What would you say the bad part is for a BEV? Personally I hope to never drive another gas-powered vehicle, hybrid or not. I'm very much addicted to the convenience and performance of modern BEVs.

I drive across Europe few times a year and covering 800 miles in one day is difficult to do in almost every BEV, maybe with the exception of Teslas. Also I had to deal with chargers in Germany a few times and it's been a pain every time(the classic - charger requires an account, the account only accepts german-registered payment card). But I'm also perfectly happy to admit that it's fine and doable just requires adju…

I hear you. This is a choice everyone has to make for themselves. Not everyone will have the same priorities or circumstances.

My longest yearly trip is ~1200km, but that's like once a year. Several times a year I do a 500km trip. On the long haul the additional refueling stops make the trip about 10% longer, on the shorter trip it has more impact, about 15%. Caveat: this is in the western US and superchargers are invariably right next to the freeway, so they don't add much time to the trip.

What really sold it for me was eliminating the trips to the gas station. That is a level of convenience it will be hard to give up.

I'm in the market right now for a new second vehicle, since I'm eliminating the need for a thirsty HD pickup capable of towing our trailer, and what I'm finding is that the market for EVs is not great in the truck space. Couple choices, both with ups and downs, and a little bigger than what I'd prefer (C'mon, Toyota, make us an electric Tacoma). So I'm faced with having to get another ICE vehicle, and the inability to fuel at home bums me out.

Re: How electric trains work and why they make interesting sounds [video]

#44

Post by bobthepanda »

exabrial wrote: post #38

I do not have perfect pitch (cool party trick), but I can identify all 8 'normal' equal temperament intervals by ear relative to a reference (If you couldn't guess, I play bass, which is a lame party trick). I was in Austria last year, and a bunch of the trains starting from a standstill had a "gradual acceleration" algorithm for their traction motors. As the drive frequency increased, you could hear the drive motor…

25kv 50/60Hz is the norm.

The German standard you are thinking of is 15kv 16.7Hz.

Re: How electric trains work and why they make interesting sounds [video]

#45

Post by exabrial »

the_mitsuhiko wrote: post #41
exabrial wrote: post #38

I do not have perfect pitch (cool party trick), but I can identify all 8 'normal' equal temperament intervals by ear relative to a reference (If you couldn't guess, I play bass, which is a lame party trick). I was in Austria last year, and a bunch of the trains starting from a standstill had a "gradual acceleration" algorithm for their traction motors. As the drive frequency increased, you could hear the drive motor…

Normally it just plays the scale: https://www.youtube.com/watch?v=-SDYdHzT7Qw But it can be configured to play other tunes. Here is a rare recording of it playing the Austrian anthem: https://www.youtube.com/watch?v=UkdQmDGU9AM (another recording: https://www.facebook.com/unsereOEBB/videos/290883783832057/ )

That was fascinating! That is different that what I remember hearing but that's exactly what I'm talking about!

Just compared it to a midi player... first video starts on a G. It may not be equal temperament? Some of the scale degrees sound just slightly flat or sharp.

Re: How electric trains work and why they make interesting sounds [video]

#46

Post by grishka »

So it's more complicated than I thought it was. Now I'm curious about our Russian trains, especially in subways. They've never made any interesting sounds, it seems. The older (Soviet-era) ones don't make any noticeable sounds at all. The newer ones just make a high-pitched whine that varies in volume (but not frequency I think) when they accelerate or brake.

Re: How electric trains work and why they make interesting sounds [video]

#47

Post by amluto »

elihu wrote: post #40
Loughla wrote: post #23

Earlier quoted context omitted.

I genuinely believe hybrid cars will be the path once we get the itch for electric cars out of our system. You get all the good parts of each engine type, with less of the bad parts of the other type.

Continuing to burn fossil fuels forever isn't really an option. At some point we'll effectively run out, but before then we'll have caused catastrophic climate change due to our CO2 emissions. Synthetic or plant-based fuels are plausible options, but synthetic fuels can't compare with battery EVs in terms of energy efficiency, and plant based fuels need crop land that's probably better used to grow food. Electric veh…

> synthetic fuels can't compare with battery EVs in terms of energy efficiency,

This is almost meaningless. If you are turning renewable energy sources into either synthetic fuel or grid power, then efficiency is irrelevant. What matters is cost (of the whole system, including distribution of the energy) and emissions (burning even carbon-neutral methane or hydrogen isn’t quite zero emission). There are startups working synthesizing fuels from air and solar energy, and they argue, fairly convincingly, that bypassing the entire electrical distribution network can more than make up for extremely low efficiency.

Also, heavier vehicles likely emit more brake and tire dust than lighter vehicles, and a series hybrid can be much lighter than a long range BEV.

Re: How electric trains work and why they make interesting sounds [video]

#49

Post by robocat »

Lwerewolf wrote: post #37
gambiting wrote: post #24

Earlier quoted context omitted.

I have a PHEV and I genuienly believe this is the best combination of both, it's so practical with upsides of both drivetrains, but also let's not kid ourselves - PHEVs are vastly more complicated than either just plain ICE or EV cars, you have a lot more stuff that can go wrong. I deal with it by just buying extended warranty for as long as they let me lol, but it's definitely a concern with them.

The Prius and other HSD cars (i.e anything with a power-split device of the Toyota variety - input-split PSD) are some of, if not flat out the most reliable and simple ICE cars. Permanent atkinson-cycle engine, no turbos because there's no exhaust gas pressure to drive them in the first place (and if there was, it'd be an inefficiency to be rooted out), bulletproof starter/generator especially since the ls600h (doubl…

> bulletproof starter

I was told this is not true for 2006 Alphard hybrid (I have one). ~USD1000 part (usually old Toyotas have cheaper parts).

And beware that older hybrids use small (e.g. 50Wh) NiMH batteries - I think they started to change to Lithium in 2017 or something

Re: How electric trains work and why they make interesting sounds [video]

#50

Post by amluto »

rootusrootus wrote: post #42
gambiting wrote: post #32

Earlier quoted context omitted.

I drive across Europe few times a year and covering 800 miles in one day is difficult to do in almost every BEV, maybe with the exception of Teslas. Also I had to deal with chargers in Germany a few times and it's been a pain every time(the classic - charger requires an account, the account only accepts german-registered payment card). But I'm also perfectly happy to admit that it's fine and doable just requires adju…

I hear you. This is a choice everyone has to make for themselves. Not everyone will have the same priorities or circumstances. My longest yearly trip is ~1200km, but that's like once a year. Several times a year I do a 500km trip. On the long haul the additional refueling stops make the trip about 10% longer, on the shorter trip it has more impact, about 15%. Caveat: this is in the western US and superchargers are in…

This truck looks fantastic, aside from the minor issue that it’s nowhere near being an actual product:

https://www.telotrucks.com/

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