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Re: Why do circuit breakers go up for on and down for off?

Cross-posted to 3 groups.

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On Wed, 10 May 2023 23:07:24 +0100, SteveW <steve@walker-family.me.uk> wrote:

> On 10/05/2023 22:04, Carlos E.R. wrote:
>> On 2023-05-10 22:31, Bob F wrote:
>>> On 3/12/2023 7:43 PM, 😎 Mighty Wannabe ✅ wrote:
>>>> rbowman wrote on 3/12/2023 10:05 PM:
>>>>> On Mon, 13 Mar 2023 00:30:39 -0000, Commander Kinsey wrote:
>>>>>
>>>>>> On Thu, 02 Mar 2023 03:09:14 -0000, rbowman <bowman@montana.com>
>>>>>> wrote:
>>>>>>
>>>>>>> On Wed, 01 Mar 2023 15:05:31 -0000, Commander Kinsey wrote:
>>>>>>>
>>>>>>>
>>>>>>>> Why were they never made of something more grippy than highly
>>>>>>>> polished
>>>>>>>> steel?
>>>>>>> https://en.wikipedia.org/wiki/Mount_Washington_Cog_Railway
>>>>>> Should be used on all tracks, then perhaps trains could stop in the
>>>>>> distance my car is required to by law.
>>>>> Do the math. A fully laden coal car weighs about 140 tons. I've
>>>>> never been
>>>>> bored enough to count cars when I stopped at a crossing but there are a
>>>>> lot of them. Let's say 30 for the sake of argument, 4200 tons plus the
>>>>> weight of the engines. Let's say 4 at 200 tons each. So, roughly
>>>>> 5000 tons
>>>>> traveling at 50 mph. That's quite a bit of kinetic energy to dump in
>>>>> 300'.
>>>>> I can hear snapping axles and see flying wheels.
>>>>
>>>>
>>>> The wheels and the rails are steel. A train can never have enough
>>>> friction to stop at a short distance. The brakes can lock all the
>>>> wheels but the train will still move forward due to inertia.
>>>
>>> All that need is train wheels made of rubber as hard as steel.
>>
>> If you do that, then those wheels will be very low friction and braking
>> will be as bad as with steel wheels.
>>
>> You need something that is soft to increase the contact surface and
>> grip. You have to choose, one thing or the other. Can't have both.
>
> Well you could have a train having steel wheels, but with rubber tyred
> wheels that could be dropped onto the track during heavy acceleration,
> heavy braking and for steep hills. But generally, steel wheels work well
> enough.

Clearly not.  https://youtu.be/p5d3NGraRqA

Talking of big trains.... https://youtu.be/fqOLoFkV5js

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Re: Why do circuit breakers go up for on and down for off? "Commander Kinsey" <CK1@nospam.com> - 2023-06-21 03:59 +0100

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