What does "LPS" on a power supply mean?

Discussion in 'General Electronics Chat' started by wayneh, Dec 10, 2015.

  1. wayneh

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    I see that the acronym stands for "limited power supply", and I've read this but I still don't quite get it. Why would you put that on the label of an AC/DC adapter? Is it just a statement of compliance with a standard? Are there examples of AC adapters that are not LPS worthy?
     
  2. Dr.killjoy

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    It's pretty much stating that a power supply can provide say 30v and 3 amp and no more .. Somethings can be ran above their specifications ,but with LPS the circuit has protection against it in order to be a safer product in case of error or failure..

    Hope it helps
     
  3. MaxHeadRoom

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    Stands for Linear Power supply.;)
    As opposed to SMPS.
    Max.
     
  4. wayneh

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    Ooh, Max, I don't think that's true. Another source.

    Here's an example. Note the "LPS" next to the pinout:
    Screen Shot 2015-12-10 at 3.05.52 PM.png
     
    Last edited: Dec 10, 2015
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  5. nerdegutta

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    Even in Swedish: "Endast för kontormaskin".

    :)
     
  6. MaxHeadRoom

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  7. mcgyvr

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    LPS = Limited Power Source
    Basically 20VDC or less output and meeting the other requirements by the use of PTC fuses,etc...
    Making it "consumer" safe to access without a tool or trained individual.

    Tests and marking requirements come from the standard bodies..
    UL60950, UL 2054,etc.. (and their IEC/EN,etc.. equivalents)
     
  8. MaxHeadRoom

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    I guess we will have to come up with another one for a Linear Supply:rolleyes:
    Max.
     
  9. mcgyvr

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    BA..Boat Anchors

    The 20V "consumer safety" requirement is also why many laptop power supplies output 19VDC..
     
  10. AnalogKid

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  11. MaxHeadRoom

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    That's a laugh, there is no way I would use anything but a linear supply on a servo or stepper system for my installations.
    Max.
     
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  12. Techno Tronix

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    If a piece of electrical or electronic equipment supplying DC power to external devices is to be installed by a third party, such as an electrician, the risk of wiring fires & electrical shock needs to be minimized. By using a Limited Power Source, the system wiring can also be reduced, saving cost.
     
  13. Hypatia's Protege

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    Perhaps in the manner of a limited disinfectant? -- IOW specified only to extent tested...?
     
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  14. Dodgydave

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    Last edited: Dec 11, 2015
  15. Hypatia's Protege

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  16. wayneh

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    There's a button for that!
     
  17. AnalogKid

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    Not big enough. There needs to be a triple-like option.
     
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