Author Topic: Test Equipment Anonymous (TEA) group therapy thread  (Read 4307204 times)

morris6 (+ 1 Hidden) and 13 Guests are viewing this topic.

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 11173
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79950 on: January 17, 2021, 11:09:56 pm »
I do know that there are many ways of looking at it, but I have no doubt at all in my mind that to produce a running car and get it into the showroom, the electric car at that point is by all accounts that read and heard about is not the greenest at all. It might well end up being greener at a certain point in its life, but there are so many factors at play here that I refuse to be drawn one way or the other.

That's a moot point. The only basis for comparison that makes any sense is to do full life end-to-end evaluations. That means for fossil fuel vehicles starting with the crude oil in the ground, and all the processes involved in making and transporting the fuel and the vehicle, operating it over a realistic normal lifetime and disposing of it at the end of that life. For a electric vehicle doing the same process, making the vehicle, making and transporting the electricity for it, operating it and the final disposal.

Talking about just one bit or the other of the full life cycle of the vehicle and its fuel allows too many opportunities for people to cherry-pick their arguments.
Isn't that more or less what I have said, but with one important differance, you're bringing into the equation the oil production and the continued operating costs throughout the cars life. I was only looking at the energy used to produce the total car, and transport it to the car showroom. From that point on I said that it could well be greener once it leaves the showroom, but that has yet to be proven either way.

There's no point in just talking about what it costs environmentally just to get the car to the showroom. It's a vehicle, not an ornament that's going to sit on the mantelpiece and do nothing. Looking at the manufacturing aspect in isolation makes no sense. If it doesn't have to be a practical vehicle that does practical work then obviously a nicely painted model of a car with no working engine or running gear would be the greenest of all. (This is obviously reductio-ad-absurdem, but that's a fitting comparison for any argument that treats a car's environment costs only up until just before the point it is put into use.)

As to the unsupported assertion that the jury's still out on the whole issue of which is greener:

EV whole lifecycle impact
Vehicle ‘lifecycle analyses’ - which take account of all the emissions right the way from the mining of ores, the manufacture of vehicles and batteries, and in-use energy consumption of petrol, diesel or electricity - show large overall CO2 savings for EVs compared to conventional vehicles.

The British Government’s key 2018 publication The Road to Zero stated that EVs “have substantially lower greenhouse gas emissions than conventional vehicles, even when taking into account the electricity source and the electricity used for battery production. Assuming the current UK energy mix, battery electric vehicles produce the lowest greenhouse gas emissions of all the energy sources and fuels assessed, irrespective of vehicle type and operation.”11

The Road to Zero estimated that in 2018 an EV car in the UK currently has total [i.e. whole life cycle] associated greenhouse gas emissions 66% lower than a petrol car and 60% lower than a diesel car.

It also estimated that by 2050 emissions from UK electricity generation would fall by 90% because renewables will dominate generation, and that the emissions associated with EV use will fall in parallel.


Thats the whole point they are purely estimates, and they are so often wrong. For instance Car A might only do 10,000 miles it is life before it is either written off in a accident or EOL and Car B could do 250,000 miles, who knows, the manner in which they are driven will also as you say, will also impact on the cars carbon footprint, to many variables to give reasonable accurate figures, unlike the carbon footprint it takes to produce the car in the first instance and get it to the showrooms in theory is a far better bet to measure the footprint of.

What happens once the vehicle is sold is anyone's guess, and it needs to take into account not just if the driver has a heavy right foot, but also the terrain, hilly, flat, tarmac, mud tracks, sand, snow etc all will greatly affect the results.
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 

Offline Saskia

  • Super Contributor
  • ***
  • Posts: 1510
  • Country: de
  • you unlock this door with the key of imagination
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79951 on: January 17, 2021, 11:14:21 pm »
Every car not produced will have a positive effect on our natural resources.
As will home office by cutting the amount of commutes.
 
The following users thanked this post: Zucca, mnementh, Specmaster, capt bullshot, cyclin_al

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 11173
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79952 on: January 17, 2021, 11:16:33 pm »
 
Right, I'm going to ask a question about electric cars, has anyone here either got one, or has driven one? I have no experience of them personally, but I have been told that they are extremely difficult to control the speed of when you are driving them. A friend of a friend claimed that they had been told by someone who has a Tesla that it was hard to control the speed of it, claiming that felt like the motor was either full power or no power with almost nothing in between. My question is, is this sort of correct? Logic tells me that it can't be, otherwise they wouldn't be allowed to be on the road?
I can't make any comment on Teslas but I recently bought a Mercedes EQC400 electric car and I am still trying to adapt to the different driving style required.

The speed control does seem more twitchy than an ICE but it is certainly not a case of full power or no power. The apparent twitchiness may be due to the throttle response of the electric motor being more rapid than an ICE so it is possible to overshoot your desired power setting by being a little bit too heavy on the accelerator pedal. More delicate control of the pedal pressure is required.

Also, the regenerative braking from the electric motor on releasing the accelerator pedal is more aggressive than what you get from the engine braking of an ICE.

Another aspect that is quite difficult is keeping within the speed limit. Since there is no audible feedback from the motor on acceleration it is very easy to creep up over the speed limit without realising it.
Now that makes more sense, thanks for your input, I think you hit the nail with the response being quicker and therefore easier to overshoot the power setting desired  :-+
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 11173
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79953 on: January 17, 2021, 11:23:09 pm »
In Sweden, as in Norway, we're doing our electricity from water, wind, sun and boiling water by neutron bowling.  An EV charged from our ...from Megawatt Valley (the likes of Drax, Ferrybridge and Eggborough)...

You're a bit behind the times. Drax now runs almost exclusively on biomass. As I write only 1% of UK demand is coming from coal. Basically we hardly burn any coal now, and only then at times of very high demand during winter or darkness. Ferrybridge and Eggborough are both decommissioned.

Do you happen to know if we still have power stations fuelled by recycled waste products? Wasn't there once a station at Edmonton that used to incinerate material sorted out at the local waste disposal unit, ie, the stuff that could not be recycled. I also seem to remember another station in Norfolk I think just off the A11 where they used to burn things like chicken manure? 
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 10959
  • Country: ca
  • *Escaping The Suck*
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79954 on: January 17, 2021, 11:25:06 pm »
Right, I'm going to ask a question about electric cars, has anyone here either got one, or has driven one? I have no experience of them personally, but I have been told that they are extremely difficult to control the speed of when you are driving them. A friend of a friend claimed that they had been told by someone who has a Tesla that it was hard to control the speed of it, claiming that felt like the motor was either full power or no power with almost nothing in between. My question is, is this sort of correct? Logic tells me that it can't be, otherwise they wouldn't be allowed to be on the road?
I can't make any comment on Teslas but I recently bought a Mercedes EQC400 electric car and I am still trying to adapt to the different driving style required.

The speed control does seem more twitchy than an ICE but it is certainly not a case of full power or no power. The apparent twitchiness may be due to the throttle response of the electric motor being more rapid than an ICE so it is possible to overshoot your desired power setting by being a little bit too heavy on the accelerator pedal. More delicate control of the pedal pressure is required.

Also, the regenerative braking from the electric motor on releasing the accelerator pedal is more aggressive than what you get from the engine braking of an ICE.

Another aspect that is quite difficult is keeping within the speed limit. Since there is no audible feedback from the motor on acceleration it is very easy to creep up over the speed limit without realising it.
Now that makes more sense, thanks for your input, I think you hit the nail with the response being quicker and therefore easier to overshoot the power setting desired  :-+

Yeah.... EVs as we have them now, acceleration and amount of applied power is not directly linear, but a matter of driver input vs a huge number of conditions only the computer knows at any moment, and output is wholly controlled by the computer.

This means that sometimes it feels much more responsive, sometimes much less, and we linear-thinking meatsacks don't exactly know what the result will be when we half-mash the pedal vs full-on stomping it.

It's sortof like having a flight-controller on a car, I suppose; the FC is always trying to keep it level to an extent, so your inputs may seem ignored sometimes and exaggerated at others.

mnem
 :o

 
The following users thanked this post: Specmaster

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 10959
  • Country: ca
  • *Escaping The Suck*
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79955 on: January 17, 2021, 11:26:24 pm »
Every car not produced will have a positive effect on our natural resources.

As will home office by cutting the amount of commutes.

But we can't have that.
We have to have centralized cubicle hives so the Great Pyramid socioeconomic structure is maintained. Ifni forbid someone who can do two people's work actually get two paychecks by working for two employers from home; or worse yet, be able to take an extra piddle break without the galactic overlords knowing it. :palm:

mnem
 ::)
« Last Edit: January 17, 2021, 11:29:06 pm by mnementh »
 
The following users thanked this post: cyclin_al

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 11173
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79956 on: January 17, 2021, 11:29:18 pm »
Every car not produced will have a positive effect on our natural resources.

As will home office by cutting the amount of commutes.

But we can't have that.
We have to have centralized cubicle hives so the Great Pyramid socioeconomic structure is maintained. Ifni forbid someone who can do two people's work actually get two paychecks by working for two employers from home, or worse yet, be able to take an extra piddle break without the galactic overlords knowing it. :palm:

mnem
 ::)
Thats a fair point and may account why there is so much resistance to working from home, because the overlords feel that you are untrustworthy to leave you to get on and do the job unsupervised  :popcorn:
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 
The following users thanked this post: mnementh

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 10959
  • Country: ca
  • *Escaping The Suck*
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79957 on: January 17, 2021, 11:31:39 pm »
Well, it's more than just that... it really is to keep you thinking that somehow the current pyramid social structure is normal, rather than the abomination it objectively is.

mnem
 |O
 
The following users thanked this post: Specmaster

Offline Cerebus

  • Super Contributor
  • ***
  • Posts: 6841
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79958 on: January 17, 2021, 11:32:15 pm »
The speed control does seem more twitchy than an ICE but it is certainly not a case of full power or no power. The apparent twitchiness may be due to the throttle response of the electric motor being more rapid than an ICE so it is possible to overshoot your desired power setting by being a little bit too heavy on the accelerator pedal. More delicate control of the pedal pressure is required.

I suspect what some people are attributing as 'twitchiness' is really about having some torque available to them to them for the first time in their driving careers. The torque curve of most EVs is much flatter than ICEs, resulting in ICE drivers who'd probably be used to a 1200, 1600 or 2000 cc petrol engine buying a vehicle that has a roughly similar ultimate power output but with much higher torque available at typical road speeds.

Take the 2013 Chevy Spark (the first EV I could find torque and power curves for). It's got about 1700 Nm of torque at the axle, or 524 Nm 'at the crankshaft' from 3mph to ~30mph, with a 0-60 time of 7.8 seconds.



The same chassis with the fastest petrol engine version available had 112 Nm at the crankshaft @ 4400rpm, and made 0-62 in 11.3s. And of course with the petrol engine, the torque at low revs is proportionally lower, unlike the EV where it's almost constant until around 40 mph (where they start to do field weakening on the motor).

So a relatively humble EV is going to have better acceleration (and hence throttle response) than a reasonably quick sports car, and is going to stomp over a petrol equivalent of the same class. If you're not used to that level of throttle response, then yeah, it's going to seem twitchy, just the same as if you jumped out of a Corsa and into a Porsche 911.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
The following users thanked this post: Specmaster

Online beanflying

  • Super Contributor
  • ***
  • Posts: 5483
  • Country: au
  • Toys so very many Toys.
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79959 on: January 17, 2021, 11:34:07 pm »
Electrical power distribution losses in the USA are about 5%.
https://www.eia.gov/tools/faqs/faq.php?id=105&t=3

Complete efficiency of Bulk grid power with a Fossil fueled base is circa 20% if it is lucky. If you charge your EV off the grid ergo the efficiency is not good.
Coffee, Food, R/C and electronics nerd in no particular order. Also CNC wannabe, 3D printer and Laser Cutter Junkie and just don't mention my TEA addiction....
 
The following users thanked this post: mnementh

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 10959
  • Country: ca
  • *Escaping The Suck*
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79960 on: January 17, 2021, 11:46:50 pm »
The speed control does seem more twitchy than an ICE but it is certainly not a case of full power or no power. The apparent twitchiness may be due to the throttle response of the electric motor being more rapid than an ICE so it is possible to overshoot your desired power setting by being a little bit too heavy on the accelerator pedal. More delicate control of the pedal pressure is required.

I suspect what some people are attributing as 'twitchiness' is really about having some torque available to them to them for the first time in their driving careers. The torque curve of most EVs is much flatter than ICEs, resulting in ICE drivers who'd probably be used to a 1200, 1600 or 2000 cc petrol engine buying a vehicle that has a roughly similar ultimate power output but with much higher torque available at typical road speeds.

Take the 2013 Chevy Spark (the first EV I could find torque and power curves for). It's got about 1700 Nm of torque at the axle, or 524 Nm 'at the crankshaft' from 3mph to ~30mph, with a 0-60 time of 7.8 seconds.

The same chassis with the fastest petrol engine version available had 112 Nm at the crankshaft @ 4400rpm, and made 0-62 in 11.3s. And of course with the petrol engine, the torque at low revs is proportionally lower, unlike the EV where it's almost constant until around 40 mph (where they start to do field weakening on the motor).

So a relatively humble EV is going to have better acceleration (and hence throttle response) than a reasonably quick sports car, and is going to stomp over a petrol equivalent of the same class. If you're not used to that level of throttle response, then yeah, it's going to seem twitchy, just the same as if you jumped out of a Corsa and into a Porsche 911.

That's part of it, but not all of it... I've built/ridden a number of homebrew e-scooters and cycles from component parts with simple ESCs. They of course have similarly flat torque curves and high power/weight ratio, but throttle response is still much more linear and predictable to meatsack brains. It's not just twitchy; it's not the same response every time you mat the pedal or feather it.

There really is a noticeable variance in how having the computer in the middle of the feedback loop makes it feel; just like some petrol vehicles with Sport/Economy modes.

Mostly, I think it's a matter of getting used to the idea of not having direct, instantaneous right-foot control, vs driving it for a week or two then going back to petrol powered vehicles, tho.

mnem
 :-//
 
The following users thanked this post: Specmaster

Offline Cerebus

  • Super Contributor
  • ***
  • Posts: 6841
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79961 on: January 17, 2021, 11:47:53 pm »
In Sweden, as in Norway, we're doing our electricity from water, wind, sun and boiling water by neutron bowling.  An EV charged from our ...from Megawatt Valley (the likes of Drax, Ferrybridge and Eggborough)...

You're a bit behind the times. Drax now runs almost exclusively on biomass. As I write only 1% of UK demand is coming from coal. Basically we hardly burn any coal now, and only then at times of very high demand during winter or darkness. Ferrybridge and Eggborough are both decommissioned.

Do you happen to know if we still have power stations fuelled by recycled waste products? Wasn't there once a station at Edmonton that used to incinerate material sorted out at the local waste disposal unit, ie, the stuff that could not be recycled. I also seem to remember another station in Norfolk I think just off the A11 where they used to burn things like chicken manure?

There's loads of biogas from compostable waste now and it's increasing all the time, and there are several (individually relatively small, a few MW or 10s of MW each) waste burning plants. Perhaps 50-60 plants for those two lumped together at the moment. A lot of the biowaste plants are at the sites of waste production and energy consumption - there's at least one big brewery that burns their brewing waste for heat and electricity generation. Unfortunately all the official statistics are lumped together as "bioenergy" which includes biomass like wood pellets, so it's difficult to pull figures out.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
The following users thanked this post: Specmaster

Offline nixiefreqq

  • Frequent Contributor
  • **
  • Posts: 775
  • Country: us
free range primate
 
The following users thanked this post: Specmaster

Offline Cerebus

  • Super Contributor
  • ***
  • Posts: 6841
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79963 on: January 18, 2021, 12:00:02 am »
I've built/ridden a number of homebrew e-scooters and cycles from component parts with simple ESCs. They of course have similarly flat torque curves and high power/weight ratio,

In your dreams buddy!  What are we talking, about 8 bhp/tonne? :)

I couldn't find a large enough dragon on a small enough scooter, so this will have to do:



Anybody got a syringe I can use to squeeze the magic smoke back into this?
 
The following users thanked this post: mnementh, Specmaster

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 10959
  • Country: ca
  • *Escaping The Suck*
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79964 on: January 18, 2021, 12:04:01 am »


LOLOL... that actually is pretty much what my current toy will look like, too.  :-DD  But I was talking aboot a much younger/slimmer me, and ni-cd powered scoots with golf-cart motors. ;)

mnem
tzzzzt!!! :bullshit:
« Last Edit: January 18, 2021, 12:22:03 am by mnementh »
 
The following users thanked this post: Specmaster

Offline mnementh

  • Super Contributor
  • ***
  • Posts: 10959
  • Country: ca
  • *Escaping The Suck*
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79965 on: January 18, 2021, 02:26:25 am »
nope.  this guy figured it out.  (maybe)

https://spectrum.ieee.org/energy/environment/a-retired-jpl-engineers-journey-from-space-probes-to-carbonneutral-farming

IIRC, lots of NOx from burning ammonia, plus it is just plain hazardous. We lived a few miles away from one of the biggest ammonia chemical reactors/storage tanks in the US where I lived in Victoria, and only a few more miles away from another huge one in Houston. We saw numerous programs warning us in both locations that if that tank or reactor had ruptured in any serious way, our entire neighborhood would have been dead before we knew aboot the explosion.

One thing people don't consider because it's so hard to measure is the global temperature rise from burning sh...tuff to make energy. Trading one kind of emissions for another is just a crutch; we don't know what those alternate emissions will do over the long haul either. Until we shift to a zero-emissions power cycle (not net-zero or carbon-offset or any of the other dozens of weasel-word excuses for not cutting the combustible fuel umbilical), we are fucking doomed.

Bottom line is that no matter how we do it, we are not going to survive long enuf to develop interstellar flight unless we stop burning stuff to make energy.

And the global warming clock just keeps ticking down; it is not going to hear the excuses or pay attention to all the bullshit. Once the balance is tipped far enough, we're fooked and no amount of whining "I'm so sorry" is going to matter; Mother Earth will shrug her shoulders and in another million years or 20 some other form of life will get their chance to do it right or fook it up.

But humanity will not be there in any recognizable form to witness it.

mnem
"Honey, where is my weeoux...?"
« Last Edit: January 18, 2021, 04:43:36 am by mnementh »
 

Offline srb1954

  • Frequent Contributor
  • **
  • Posts: 355
  • Country: nz
  • Retired Electronics Design Engineer
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79966 on: January 18, 2021, 03:03:51 am »
I suspect what some people are attributing as 'twitchiness' is really about having some torque available to them to them for the first time in their driving careers. The torque curve of most EVs is much flatter than ICEs, resulting in ICE drivers who'd probably be used to a 1200, 1600 or 2000 cc petrol engine buying a vehicle that has a roughly similar ultimate power output but with much higher torque available at typical road speeds.
That may be true for some EV buyers but in my case I wasn't upgrading from some low-performance vehicle - I actually downgraded slightly in moving from a high performance AMG sports SUV to the EV.

Even so I still think the EV has a "twitchier" throttle response compared to the petrol-engined equivalent.

 

Offline mansaxel

  • Super Contributor
  • ***
  • Posts: 1343
  • Country: se
  • SA0XLR
    • My very static home page
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79967 on: January 18, 2021, 06:04:10 am »
In Sweden, as in Norway, we're doing our electricity from water, wind, sun and boiling water by neutron bowling.  An EV charged from our ...from Megawatt Valley (the likes of Drax, Ferrybridge and Eggborough)...

You're a bit behind the times. Drax now runs almost exclusively on biomass. As I write only 1% of UK demand is coming from coal. Basically we hardly burn any coal now, and only then at times of very high demand during winter or darkness. Ferrybridge and Eggborough are both decommissioned.

I actually already knew this, but I think from reading about them (and watching videos on boating on the Aire) that those three are some of the more iconic ones in the Valley, so that's why I chose them. More of a figure-of-speech than a power generation report :-D

Add-on: A very fitting comparison as to why it is sensible to run an EV, even from coal-sourced electricity, is to compare the pollution, local foremost but also global, from thousands of small coal fires in semi-detached housing to the centralised combustion in one of those big ones.

Offline cyclin_al

  • Regular Contributor
  • *
  • Posts: 232
  • Country: ca
  • VE3TSD / VA2XAR
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79968 on: January 18, 2021, 06:54:28 am »
Any good bearing supply house will carry highly polished and hardened bearing grade steel balls.

Yep, true .... but ....
Here in the great white north, a gross (144) of those ball bearings will cost you in the vicinity of $9 at a good bike shop.  At a not-so-good modern bike shop, all they will have is one bike brand of sealed bearing units.  At a bearing shop, expect to pay about $0.75 per ball; they must be genuine imperial based on that price...
 

Offline Saskia

  • Super Contributor
  • ***
  • Posts: 1510
  • Country: de
  • you unlock this door with the key of imagination
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79969 on: January 18, 2021, 07:06:16 am »
@mansaxel I tend to disagree. I still think CNG is one of the best ways to drive your car. CNG is just burning cow farts instead of letting it go into the atmosphere. The only problem is: we need to capture those farts to recycle them.

Now, if we composted all those politicians and used them to propel our cars they would be doing something useful for a change.
 
The following users thanked this post: Zucca, mnementh, bd139

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 11173
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79970 on: January 18, 2021, 08:59:34 am »
Thinking back to the topic of EV cars and that it maybe the torque that makes speed control more difficult when compared against smaller petrol (gas) powered cars because EV cars do have huge amounts of torque almost instantly available whereas petrol engines develop their torque typically around 4,000RPM. I remember when I first switched from petrol-engined cars to diesel that diesel, that it struck me as being difficult in traffic to control the speed effectively. Why do I say this, because I remembered that if I parked close to a kerb, and it was necessary to mount the kerb from a standing start, the petrol engine need to be given a bit of right boot to climb it, otherwise it is likely to stall, whereas, depending on the engine size, a diesel would tend to climb up the kerb at idle speed due to that increase in low down grunt. These days after many years of having diesel powered cars, I have become accustomed to it and adjusted my right foot behaviour accordingly.  :popcorn:
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 

Offline Cerebus

  • Super Contributor
  • ***
  • Posts: 6841
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79971 on: January 18, 2021, 09:09:13 am »
Thats the whole point they are purely estimates, and they are so often wrong. For instance Car A might only do 10,000 miles it is life before it is either written off in a accident or EOL and Car B could do 250,000 miles, who knows, the manner in which they are driven will also as you say, will also impact on the cars carbon footprint, to many variables to give reasonable accurate figures, unlike the carbon footprint it takes to produce the car in the first instance and get it to the showrooms in theory is a far better bet to measure the footprint of.

What happens once the vehicle is sold is anyone's guess, and it needs to take into account not just if the driver has a heavy right foot, but also the terrain, hilly, flat, tarmac, mud tracks, sand, snow etc all will greatly affect the results.

So I take it you think that a hundred years of private vehicle ownership isn't enough experience for us to have accumulated sufficient data to accurately predict how people use privately owned vehicles? Obviously there is a huge body of statistics in the hands of governments and motor vehicle manufacturers that says otherwise. Or perhaps you think that 100 years of engineering experience building the same isn't a sufficient basis for predicting the likely lifetimes and failure modes of their components over that lifetime? If that's true then I think we'd better throw the whole profession of engineering in the bin.

Nope, we're got quite enough data and experience to be able, as engineers and scientists, to come to some reasonable conclusions as to the environmental impact of substituting EVs for ICE vehicles. And people have, and have published that data and those conclusions. On that basis, I don't think there's any element of the "jury still being out".  The only reason that there might appear to be, to some people, is that there are a whole shitload of vested interests involved who'd like to muddy the waters. The tactic of falsely claiming a need for "further study" is such an old delaying tactic that it was handed out in advice on sabotage in WWII.

Quote from: OSS Simple Sabotage Manual
(11) General Interference with Organisations and Production
(a) Organizations and Conferences
(1) Insist on doing everything through "channels." Never permit short-cuts to be taken in order to expedite decisions.
(2) Make "speeches." Talk as frequently as possible and at great length. Illustrate your "points" by long anecdotes and accounts of per­ sonal experiences. Never hesitate to make a few appropriate "patriotic" comments.
(3) When possible, refer all matters to committees, for "further study and considera­tion." Attempt to make the committees as large as possible — never less than five.
(4) Bring up irrelevant issues as frequently as possible.
(5) Haggle over precise wordings of com­ munications, minutes, resolutions.
(6) Refer back to matters decided upon at the last meeting and attempt to re-open the question of the advisability of that decision.
(7) Advocate "caution." Be "reasonable" and urge your fellow-conferees to be "reason­ able" and avoid haste which might result in embarrassments or difficulties later on.
(8 ) Be worried about the propriety of any decision — raise the question of whether such action as is contemplated lies within the juris­ diction of the group or whether it might conflict with the policy of some higher echelon

(Some of us may also recognise elements of the above as "good business practice" as promulgated by a certain class of PHBs.  :))

As engineers and scientists we ought to be immune to this kind of propaganda, especially in this day and age where getting your hands on peer reviewed science and engineering publications packed with hard facts is a few clicks away on the Internet. Instead, as has been evidenced many times by the too-ing and fro-ing about EVs across the whole of this forum, we as a body seem to be just as gullible as readers of the Daily Mail or the National Enquirer.
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Offline Specmaster

  • Super Contributor
  • ***
  • Posts: 11173
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79972 on: January 18, 2021, 09:12:55 am »
And back to TEA, this message just arrived, so I have my spray bottle of IPA already to disinfect the meter first before inspecting and powering it up, more on it later.  :-+
Who let Murphy in?

Brymen-Fluke-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo-Kyoritsu-Amprobe-ITT-Robin-TTi
 

Offline McBryce

  • Super Contributor
  • ***
  • Posts: 1907
  • Country: de
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79973 on: January 18, 2021, 09:22:32 am »
Regarding the safety of EV's and their batteries, there is no real safety advantage between Cylindrical and Prismatic packs. Cylindrical have some minor cooling advantages, but getting the same power density as prismatic packs is difficult. Mechanical strength is important, but the electronic monitoring will react well before any mechanical component has failed. The batteries are monitored (voltage, current, Charge state, State of Health and temperature) on the cell pack level, so even if a single cell shorted, the system will react in microseconds and like any ICE vehicle, the entire power source is also cut as soon as any crash is detected.

As for the driving experience, as mentioned above, it's the torque curve that people notice at first. People are used to an engine needing time to react, especially if they drove a diesel up to then. The motor definitely isn't an ON/OFF situation, it's just like any variable motor control.

I won't comment on the environmental or infrastructure aspect, that's politics not engineering and will be different for every country.

McBryce.

* This information/opinion doesn't come from a report, I've worked in EV and EV Baterry development for almost 20 years, including work on the Prius.
 

Offline Cerebus

  • Super Contributor
  • ***
  • Posts: 6841
  • Country: gb
Re: Test Equipment Anonymous (TEA) group therapy thread
« Reply #79974 on: January 18, 2021, 09:23:43 am »
Any good bearing supply house will carry highly polished and hardened bearing grade steel balls.

Yep, true .... but ....
Here in the great white north, a gross (144) of those ball bearings will cost you in the vicinity of $9 at a good bike shop.  At a not-so-good modern bike shop, all they will have is one bike brand of sealed bearing units.  At a bearing shop, expect to pay about $0.75 per ball; they must be genuine imperial based on that price...

A gross? I thought the gross went out with Gentleman's Outfitters pricing everything in Guineas. I'll remember that next time I hear some Canahouvian waxing lyrical about how superior they are to their southern cousins because they've managed to get to grips with the metric system instead of measuring things in bushels per league or furlongs per fortnight.  :)
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf