- Thread starter decca
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Wedg1e
They call me Mr. Bodge-angles
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Too right. There's a ditty called 'The offside rule for women' that attempts to explain it with shoes and handbags; I don't understand it either way
rtbcomp
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I think it has a place to get principles across to people who aren't of an electrical bent, but it soon falls down. If taken too literally the video gives the impression that DC will spill out into the open and AC doesn't need a return path, put I think using the syringes to explain the relation between the 3 phases is more appealing than drawing diagrams. No analogies are perfect.
gordon stephenson
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I remember going to a lecture given by Keelavite Hydraulics 50 years ago, and it was stated that hydraulics could do anything that DC electricity could do, Even a light bulb with a fine capillary tube and enough pressure forced through it to make it glow.
rtbcomp
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Equivalent of an electromagnet?
I went to a lecture by someone from Racal c1968 - the guy was describing a diode that could emit light, "it might become popular" he said.
Pete.
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I hear this a lot but the truth is that 3 phase power is the same potential to earth as ordinary 240v mains. Unless you're extraordinarily unlucky to make a path from one of the live wires to another with your body, any shock you get will be just as if you got it from your household socket.
gordon stephenson
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Electro magnet might be possible if the hydraulics drove a generator to power the magnet?
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He's using old (red yellow blue) water, not harmonised (brown black grey) water
Exuptoy
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The one bit I found disturbing was when advised on the requirements for arc flash on our HV equipment on board my old FPSO, that the clothing requirements for LV was much greater than it was for HV!!
IIRC it was something like arc rated jacket, shirt and trousers was needed for LV along with a sock hood, face shield and gloves as opposed to hood, shield, gloves and arm covering for HV!
How it was explained to me was, it is far more common for low voltages, such as 440v, to have much more significant arc flash hazard levels because the fault currents are much higher and longer the clearing time of the protective devices under high fault currents. I wouldn't want to be exposed to it in either case!
IIRC it was something like arc rated jacket, shirt and trousers was needed for LV along with a sock hood, face shield and gloves as opposed to hood, shield, gloves and arm covering for HV!
How it was explained to me was, it is far more common for low voltages, such as 440v, to have much more significant arc flash hazard levels because the fault currents are much higher and longer the clearing time of the protective devices under high fault currents. I wouldn't want to be exposed to it in either case!
rtbcomp
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That's cheating!
I suppose you could squirt water through a venturi and use the vacuum to pick things up, but you wouldn't get the 'like poles repel, unlike poles attract' effect.
normspanners
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Well I thought it was a very good way of explaining the theory to------ thickos 
-------
that dont understand, I wasnt told, I just worked it out when a boy, BUT I was interested in that sort of thing. Many people dont understand even how batteries work, or the difference between dc and ac one of my lads has done an electrician's course and I still have to explain some of the finer points ! another one hasnt a clue and I find it scary, coz he doesnt listen-- at 25. Well he listens to his headphones------- on the play station !! but doesnt understand why they are not plugged in but the play station has to be.
------- that dont understand, I wasnt told, I just worked it out when a boy, BUT I was interested in that sort of thing. Many people dont understand even how batteries work, or the difference between dc and ac one of my lads has done an electrician's course and I still have to explain some of the finer points ! another one hasnt a clue and I find it scary, coz he doesnt listen-- at 25. Well he listens to his headphones------- on the play station !! but doesnt understand why they are not plugged in but the play station has to be.
decca
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Well I thought it was a very good way of explaining the theory to------ thickos
Bit disappointed with this response although putting the couch and smiley face makes it ok.........Not!!
normspanners
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HEHE Well we get elect'eds pushed into our lives then sucked out again and we end up paying a fortune for each of them.
rtbcomp
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They'd be classed as waste so you'd have to pay to have them disposed of.
