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| The "All American Five", & more dangers!! |
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| rsjsouza:
I told this story somewhere else in this forum, but I grew up with non-polarized and non-grounded round and flat plugs all my life in Brasil. The standard until the mid 2000s was to try to be friends with the US and some of Europe's standards and we got away with the ground plug in most types. With the explosion of the PC era in the 1990s, the three prong grounded US plug started to become quite common and, with the existing non-grounded and non-polarized outlets, the obvious solution was to rip apart the third pin - not without that tingling sensation when one touched the metal housing. Worse, a lot of people started warning about cutting the third pin and therefore a market of "electricians" was created, retrofitting the existing outlets by simply replacing the outlet but not wiring the ground. Most houses and buildings were only two-wire circuits unitl 1994, where the new constructions required the ground wire but everything else was grandfathered. Fast forward to mid 2000s, the stupid swiss standard was approved, which was pretty much incompatible with everything else in existence in the country and in the world and from night to day it obsoleted hundreds of millions of appliances, equipment and parts. Someone made wads of cash then. The newer standard is safer? You bet. The older standard was useable? Of course! Did people get shocked? Yes, but it was considered a growing pain, really. Given that electric appliances and gadgets were not as ubiquitous as today, people gave it the proper respect it requires and used it in a much more responsible way. I see the case with the safe/unsafe cars the same: in my experience, the individuals had much more respect for the act of driving due to the mechanical limitations of a car and knew they could really die if pushed above certain limits - the safe car propaganda tends to infuse a sense of indestructibility, where people become so confident they even consider (and several actually do) deviate their eyes from the traffic to interact with their smartphones. And no, I am not saying that we should roll back the incredible progress done with the safety aspects, but we should equally stress the dire consequences even with all this techno-nanny gizmos. As others have said, you can't make the world "safe at all costs". A part of the responsability has to come from the individual. |
| Electro Detective:
@ rsjsouza: great comment :-+ but someone has to say it..that's an awesome collection of wrist bands in that picture ;D Iron Man would be green with envy :rant: |
| rsjsouza:
--- Quote from: Electro Detective on April 30, 2020, 11:50:23 pm --- @ rsjsouza: great comment :-+ but someone has to say it..that's an awesome collection of wrist bands in that picture ;D Iron Man would be green with envy :rant: --- End quote --- ;D ;D ;D I have never saw them from this angle... you are right. |
| GlennSprigg:
--- Quote from: TimFox on April 30, 2020, 01:24:41 pm --- --- Quote from: Tom45 on April 30, 2020, 04:46:18 am --- --- Quote from: TimFox on April 29, 2020, 04:03:42 pm ---... Consolidated Edison in New York finally ceased DC distribution totally in 2007. ... --- End quote --- To be fair to Con Ed, I think they carried on with DC service for such a long time because there were a few elevators in NYC that used DC motors. Substituting AC motors and controls was apparently deemed to be a bigger problem than just continuing DC service to the few ancient DC installations. A search brought this article: https://cityroom.blogs.nytimes.com/2007/11/14/off-goes-the-power-current-started-by-thomas-edison/ Apparently the hold outs haven't converted to AC. They just installed AC to DC converters on site. --- End quote --- Yes, the very late dropping of DC service in New York was related to elevators. However, before the War, there was a lot of DC distribution in New York and Boston, a big problem for transformer-operated equipment and the origin of AC-DC jokes (another topic). Around 1965, I visited the roundhouse of the Duluth, Missabe, and Iron Range Railroad in Proctor, MN, which still had one or two Yellowstone 2-8-8-4 simple articulated steam locomotives (the most powerful ever built, slightly more tractive effort than the more famous Big Boys of the Union Pacific). The big electric motors ran on 25 Hz power for historical reasons, which they could still obtain from Minnesota Power and Light Co., although the rest of us enjoyed modern 60 Hz power. --- End quote --- Wasn't the U.S. still using DC for some TRAMS for quite a while?? Also, until recently seeing a "Mr. Carlsons Lab" radio restoration video, where it had an extra large transformer, designed to work down to 25-hz supply frequency, had I ever HEARD of the use of 25-hz !! Also, to rsjsouza, regarding Earthing. I don't know how 'Earths' are set up in the U.S., but here in Australia, it goes like this... The 'Earth' is not supplied to the property. An Earthing stake is driven into the ground close to the Switchboard/Meterboard. All the earth wires within the property (outlets/lights) go back to a dedicated earth-termination bar in the main switchboard. The Earth-stake in the ground is also connected to this bar. However, 'we' ALSO have a hefty cable link in the switchboard, linking that Earth-Bar to the Neutral-Bar, under what we call 'M.E.N.', meaning a 'Mains-Earth-Neutral' system. So that the Neutral is always referenced to Earth also! Often, old un-earthed circuits simply need the addition of a separate earth wire, (if not included in the cables), to bring it up to spec. And we 'virtually' have no power outlets without a built in switch, which obviously switches the Active. And our outlets are automatically 'polarized' due to the diagonal layout of the prongs. :) |
| rsjsouza:
--- Quote from: GlennSprigg on May 01, 2020, 12:33:34 pm ---Also, to rsjsouza, regarding Earthing. I don't know how 'Earths' are set up in the U.S., but here in Australia, it goes like this... The 'Earth' is not supplied to the property. An Earthing stake is driven into the ground close to the Switchboard/Meterboard. All the earth wires within the property (outlets/lights) go back to a dedicated earth-termination bar in the main switchboard. The Earth-stake in the ground is also connected to this bar. However, 'we' ALSO have a hefty cable link in the switchboard, linking that Earth-Bar to the Neutral-Bar, under what we call 'M.E.N.', meaning a 'Mains-Earth-Neutral' system. So that the Neutral is always referenced to Earth also! Often, old un-earthed circuits simply need the addition of a separate earth wire, (if not included in the cables), to bring it up to spec. And we 'virtually' have no power outlets without a built in switch, which obviously switches the Active. And our outlets are automatically 'polarized' due to the diagonal layout of the prongs. :) --- End quote --- Glenn, the standard here varies a lot around the country - since I don't work in the professional electrician field, I wouldn't risk throwing my inaccurate hints. In my house I have a ground wire being fed to the panel, but I didn't pay attention if there is a connection to a bar near my meter - it could be done that way or perhaps there is a larger ground bar in the neighbourhood. Overall it seems the ground connection is alright as no tingling sensation happens with grounded chassis and no equipment was ever damaged due to lightning (and there is a LOT of lightining where I live). |
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