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New aerial type?

Discussion in 'Audio Visual' started by Draughtsman, 5 Jul 2021.

  1. SUNRAY

    SUNRAY

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    Ironically I did but deleted it in an edit it as part of removing an insult.
    The biggest I've seen so far is 20,000,000MAh. That's 20 billion Ah.
     
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  3. Harry Bloomfield

    Harry Bloomfield

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    Quick, buy one - we could do with more backup for the National Grid :)
     
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  4. SUNRAY

    SUNRAY

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    Silly me that's now 20 trillion Ah with progression yes one of those could do wonders for the grid if they come precharged.
     
  5. bernardgreen

    bernardgreen

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    Are you sure it is not 20.000,000
     
  6. Lucid

    Lucid

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    It's irony at its highest that you're advocating progression - the argument being that if the description is in use then that somehow makes it valid - and yet here you are pointing out how a standard that hasn't been observed causes this problem with capacity rating description of a battery.

    I'm only aware of Amp-hours and milliamp-hours relating to battery capacity. There is no MegaAmp-hours. But you know, that's because I follow the standards.

    20,000,000MAh should read 20,000,000mAh, which of course simplifies to 20,000Ah. That would be a hell of a battery. More correctly, it's likely that the battery is 20,000mAh. These kind of screw-ups are just what happens when one follows the idea of an anything goes progression.
     
  7. SUNRAY

    SUNRAY

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    Yes of course I understand the stupidity of the incorrect description referred to and totally agree with your figures. I imagine the true capacity is supposed to be 20Ah but even that I'd treat with scepitism, as the only one of this sort of thing I've tested (By actual useage) was listed at 12,000mAh and powering a radio receiver drawing a fairly consistant 100mA or so lasted under 2 days rather than the expected >5 days (Maybe a bit less due to the fairly high discharge rate), or around 4.5Ah so not even half, the actual cells used were listed at something under 4Ah (Possibly the common 3.7Ah). After that I used a car battery (likely to have been 80Ah) which ran for the remainder of the summer season.

    I've worked with batteries measured in KAh and 20KAh was not that rare usually with cells of 5KAh max (2V lead acid cells being 3x2x4ft high) and testing them in KAh alongside batteries in mAh & Ah, and mains measurements in A, W/VA, Wh, KA, KW/KVA, KWh, MW/MVA & MWh. It's never occurred to me MAh, although I don't recall ever using it, would be excluded despite being a valid SI element. rather like dm & Dm, Oh sorry I must keep up with progress... dm & dam (decimetre & Decametre). 50 years ago I learnt that in SI anything sub base was a small letter and anything base superior to be a capital letter but even that has changed.
     
    Last edited: 2 Oct 2021
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  8. SUNRAY

    SUNRAY

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    Keep an eye on the adverts, they are eye watering these days. They seemed to hover around 20,000 to 100,000mAh (20 to 100Ah) for a while then the competition seemed to kick it.
     
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