Electrical question. Monitor Power supply.

Discussion in 'Science and Technology' started by Trinity Gingerbread, Jun 11, 2019.

  1. Trinity Gingerbread

    Trinity Gingerbread Time is the thief of life Premium Member

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    Hey guys just wondering.

    The reason I changed screens was my samsung died last night, but what I can't test at the moment was if it was the panel that is dead or the external power supply brick.

    The samsung power adapter is running at 14v 1.7amps

    The LG screen I am using now is 19v 1.4amps

    Could I plug the samsung power brick into this and see if that is in fact still functional?

    Barring that I could get a multimeter and test it, just have to buy a new multimeter.
     
  2. Asbo Zaprudder

    Asbo Zaprudder Vice Admiral Admiral

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    Asbo Zaprudder
    As long as the connector and its polarity are compatible, it's unlikely you'd damage the LG screen as it requires a higher voltage but why risk it? If you don't have equipment with the same voltage, amperage, connector polarity, and connector type with which to test the supply, I suggest you buy a multimeter. They're not that expensive and it's always good to have one handy.

    I have two multimeters and an adjustable power supply with a connector adapter. This appears to have cowed all my power adapters into submission as they never seem to fail. ;)
     
  3. Trinity Gingerbread

    Trinity Gingerbread Time is the thief of life Premium Member

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    Oh I am definitely getting the multimeter and both power supplies have the same polarity on the output plug.

    I don't think I'll risk the LG with the other power pack. It's just a lovely screen and brand new. The multimeter will tell me if the other power supply has died, if not then it was the other screen I'll feel somewhat relieved.
     
  4. bigglesworth

    bigglesworth Commander Red Shirt

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    Oct 2, 2017
    I'm not sure it would even work...

    The Samsung PS is outputting 14VDC, 1.7A and I suspect the Samsung panel splits that off into 12V, 5V, 3.3V, etc... for the various internal components. Conversely the LG PS is outputting 19VDC, 1.4A and again the panel regulating the potential down to 12V, 5V, 3.3V, whatever.

    If the LG panel is expecting the 19V and 14V is introduced, the stepped down voltages are going to be 8.8V, 3.7V, 2.4V, etc...

    Also, the current (amperage) on the Samsung is slightly higher. Some electronic components are very sensitive to that. I recall that in the US Navy, for certain equipment, we'd have to use old Simpson analog multimeters at their lowest setting to test resistance as the electronic meters introduced too much current and would toast the integrated circuits. That being said, I haven't done any electronic troubleshooting/repair nor looked at a schematic in 20 years, so take my advice for what it's worth.
     
  5. Trinity Gingerbread

    Trinity Gingerbread Time is the thief of life Premium Member

    Joined:
    May 31, 2015
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    No, no that's fine. I didn't end up doing that kind of test anyway and the power brick was dead anyway when put on a multimeter. I opened the screen just to see if there was any other damage and one of the capacitors had popped its lid releasing all its gooey goodness. So yeah that was toast.