DC Adapter question

Discussion in 'Computer Information' started by Ann-Marie, Jun 7, 2005.

  1. The term was yours, and it is silly (and all the other adjectives
    you used to describe it). Which is why *I* didn't use it.
    If you think so, you'd better take a closer look at real life
    regulators!

    Sometimes the whole point of a "regulator" is ripple reduction
    at 60 Hz and it's harmonics. Sometimes the whole point of a
    "regulator" is to provide regulation within a very minimal
    range.

    And sometimes "regulation" means within 20%, sometimes 10% and
    sometimes 0.1%.

    I suppose I could go on with a longer list of ambiguities, but
    those are all well known and should be enough to demonstrate
    that your statement about "regulation" just doesn't have a lot
    of meaning. The point is that not all regulated power supplies
    maintain the same voltage with no load, and that some regulated
    power supplies do not regulate well except within a specified
    load range. Regardless, your original statement tried to
    generalize something specific that generally may not be true.
    I'm sorry you don't understand the technical aspects, but that
    does suggest you perhaps shouldn't try to post technical
    answers.
    A live "5V 2A SMP wall wort".


    Whatever, this conversation is finished. You can have the last
    words. Just do try for something a little better than
    unregulated regulated power, eh?
     
    Floyd L. Davidson, Jun 9, 2005
    #41
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  2. Funny you mention "real life" and then wander off into a fantasy land of
    speculation.

    The fact of the "real life" matter is that none of your "sometimes"
    speculations apply to SMP wall worts.

    That is what I meant by your mash of mumbo jumbo. One can 'speculate'
    anything but the real world case is that a regulated wall wort will have
    none of the characteristics you ponder as 'possible'.

    Oh I understand them just fine and design them too. The difference is I
    don't try to obfuscate the practical matters with theoretical 'anything
    could be' speculations.
    Wouldn't you be terrified it could be one of those unsuitable
    'possibilities' of inferior regulation you just ranted about?

    No need as it's appropriately silly as it stands.
     
    David Maynard, Jun 11, 2005
    #42
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  3. I just happen to have a DLink DI-614+ here. DLink uses several
    sources of power supplies. This one is a:
    Fairway Electronics LTD
    Model: WN10A-050U
    Input: 100-240VAC 1.0A Max 50-60Hz
    Output: +5.0VDC 2.5A
    With such a wide input voltage range, it has to be a switcher.
    http://www.ncs-fairway.com/catalog/page10.pdf
    Note that the 5VDC output is regulated (to 5%).

    I dunno about the 70% efficiency. Seems a bit low.
    Interesting that the sticker says 2.5A while the data sheet says 2.0A
    output. Oh-oh.
     
    Jeff Liebermann, Jun 11, 2005
    #43
  4. Thanks. Knew it had to be unless someone had invented featherweight iron ;)
    Oh, I wish that was the one that came with mine. Mine has the plug on the
    end, which means it sticks almost 3 inches out the wall, if you plugged it
    into a wall outlet.
    That's the tolerance. They don't seem to mention load/line regulation %.
    Look at the second 5 volt job 5 lines down: 2.5A 12.5W
     
    David Maynard, Jun 11, 2005
    #44
  5. Ann-Marie

    Phil Weldon Guest

    But wait! Couldn't the transformer be very light if it were ferrite and
    worked at a much higher frequency than 60 Hz? Oh, never mind.

    Phil Weldon
     
    Phil Weldon, Jun 11, 2005
    #45
  6. Most of mine are plugged into power strips where such a compact
    arrangement is benificial. However, there are ways to deal all manner
    of wall warts.
    http://802.11junk.com/jeffl/pics/drivel/slides/wall-wart-01.html
    Oops. I didn't notice the "U" suffix. Thanks.
     
    Jeff Liebermann, Jun 11, 2005
    #46
  7. Hehe. Sure. That's how a switcher does it.
     
    David Maynard, Jun 11, 2005
    #47
  8. David Maynard, Jun 11, 2005
    #48
  9. do you not find that the adaptors in the middle get kinda hot? I can
    practically cook toast on the power strip under my desk at work.
     
    Mark McIntyre, Jun 11, 2005
    #49
  10. Nope. I just checked with my wiz-bang new optical IR thermometer. My
    pile of 8 wall warts is running quite cool. I added two switcher wall
    warts to the top of the brown octopus connectors. Highest temperature
    was 83F (ambient is 71F). Most of the wall warts in the photo are not
    running. They go to my HP scanner, PCR-1000 receiver, Belkin KVM
    switch, Kyocera PDA phone, Radio Shock RC electric car charger, and
    other devices that are usually turned off. The ones running my
    BEFW11S4 and Efficient 5260 DSL modem are always on, but run quite
    cold. I suspect that if I turned everything on, it might get a bit
    warm. I could measure the dissipation and calculate the heat rise
    (based on black body radiation and surface area), but I'm lazy today.

    I've had wall warts that ran very hot. Hot enough to burn my fingers
    when I touched them. The nice thing about the hot ones is that they
    don't last very long. I have a fair collection of replacements and
    connectors. A substantial number of my operating wall warts are
    replacement.

    Incidentally, my photo of the octpus connectors plus power strip made
    the rounds on an electrical safety mailing list. The result was some
    really interesting email from electricians suggesting I was derranged,
    isane, dangerous, unsafe, and in violation of several NEC code
    sections. Absolutely nobody thought it was a good idea. Oh well.

    The problem with the arrangement in the photo is that I have to glue
    the brown octopus connectors to the power strip, or it will tend to
    fall over. Xformers can only be installed in pairs. It works, but
    isn't the greatest. Currently, I'm using several of those overpriced
    flat two row power strips that are made to handle wall warts. The
    density is about the same but the plugs are much easier to deal with.
     
    Jeff Liebermann, Jun 11, 2005
    #50
  11. Ann-Marie

    VWWall Guest

    Here's an easy way to do it:

    http://www.cyberguys.com/templates/searchdetail.asp?T1=121+2570

    I have used a "power control center" on every computer I've built.

    http://www.cyberguys.com/templates/searchdetail.asp?T1=112+0143&dept=&search=&child=

    With the little cords shown above they are very useful devices for
    turning the power on only to the devices in use. They claim "surge
    suppession", but I would not even consider them for that; the built in
    circuit breaker might prevent a severe overload from tripping the mains
    breaker. They make a good base to set the monitor on. :)
     
    VWWall, Jun 12, 2005
    #51
  12. Ann-Marie

    Phil Weldon Guest

    Thanks for the URL. Have you ever seen a 3-prong AC adapter that attaches
    permanently (serrated contacts on the female end) to a USA 3-prong AC power
    plug and has a 'flip-up' ground pin. I've used it on 120 VAC power plugs
    for temporary lighting, but no longer know of a source. Any ideas? The URL
    you posted is quite useful, but does not seem to have that type of adapter.

    Phil Weldon
     
    Phil Weldon, Jun 12, 2005
    #52
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