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  • Scotty! We need Warp power now! [can't deduce 5v draw!]

    From Louis Ohland@21:1/5 to All on Sat Mar 18 05:52:46 2023
    Had a few questions on 95 PSU load. At first, I thought just monitoring
    the AC amps in would give us wattage. Not quite so.

    There are two "levels" of power, one being the triple device power
    sockets. +5v and +12v. SIMMple to deduce, read drive datasheet, done.
    Just leave all taps disconnected, SIMMplify reading planar power draw. I ass-u-me the three taps are overload protected separately from the main overload. Dunno. But it makes sense that a device could be pulling more
    power than it should, yet not enough to pop the breaker for overall current.

    The second "level" is the 21 pin planar power plug. We got +5v, +12v,
    and -5v.

    It seems possumble that we measure the wattage into an unconnected PSU,
    using either a paperclip on the 8595 PSU, or the test button on the 95A
    PSU. We get a "no-load" wattage, just for the PSU.

    Now we can plug it into the planar, and test with one set of SIMMs, then
    two, then three, then four. -MAYBE- the SIMM power draw is not lost in
    the overall efficiency of the PSU.

    The best weg would be to measure all +5v at once with a clamp. The
    planar pretty much exclusively uses +5v, so we aren't missing much by
    letting -5v go unmeasured.

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  • From Grant Taylor@21:1/5 to Louis Ohland on Sat Mar 18 10:08:06 2023
    On 3/18/23 4:52 AM, Louis Ohland wrote:
    The best weg would be to measure all +5v at once with a clamp. The
    planar pretty much exclusively uses +5v, so we aren't missing much by
    letting -5v go unmeasured.

    I would think that it would be possible, if not annoying, to measure the
    actual voltage & current draw (thus wattage) of each rail if one has
    enough meters and proper connectors to make and place a pig tail between
    the PSU and the motherboard.

    Though I suppose that someone would need to really want to do that to go
    to the trouble to do so.



    --
    Grant. . . .
    unix || die

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Louis Ohland@21:1/5 to Grant Taylor on Sat Mar 18 11:44:03 2023
    Uh, the 21 pin AMP connector is unobtanium.

    Grant Taylor wrote:
    pig tail between the PSU and the motherboard.

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Grant Taylor@21:1/5 to Louis Ohland on Sat Mar 18 11:25:57 2023
    On 3/18/23 10:44 AM, Louis Ohland wrote:
    Uh, the 21 pin AMP connector is unobtanium.

    I was thinking sacrificial / donor parts from a dead system plainer and
    power supply.

    I hear that it's possible to do amazing things with 3D printers these days.



    --
    Grant. . . .
    unix || die

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Louis Ohland@21:1/5 to Grant Taylor on Sat Mar 18 13:46:28 2023
    Oddly, I -MIGHT- have foundt both wire and board connectors. Sendt links
    to MAJ Tom

    Grant Taylor wrote:
    On 3/18/23 10:44 AM, Louis Ohland wrote:
    Uh, the 21 pin AMP connector is unobtanium.

    I was thinking sacrificial / donor parts from a dead system plainer and
    power supply.

    I hear that it's possible to do amazing things with 3D printers these days.




    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From moussa@21:1/5 to Louis Ohland on Mon Mar 20 09:40:35 2023
    On 18/3/23 18:52, Louis Ohland wrote:
    Had a few questions on 95 PSU load. At first, I thought just monitoring
    the AC amps in would give us wattage. Not quite so.

    There are two "levels" of power, one being the triple device power
    sockets. +5v and +12v. SIMMple to deduce, read drive datasheet, done.
    Just leave all taps disconnected, SIMMplify reading planar power draw. I ass-u-me the three taps are overload protected separately from the main overload. Dunno. But it makes sense that a device could be pulling more
    power than it should, yet not enough to pop the breaker for overall
    current.

    The second "level" is the 21 pin planar power plug. We got +5v, +12v,
    and -5v.

    It seems possumble that we measure the wattage into an unconnected PSU,
    using either a paperclip on the 8595 PSU, or the test button on the 95A
    PSU. We get a "no-load" wattage, just for the PSU.

    Now we can plug it into the planar, and test with one set of SIMMs, then
    two, then three, then four. -MAYBE- the SIMM power draw is not lost in
    the overall efficiency of the PSU.

    The best weg would be to measure all +5v at once with a clamp. The
    planar pretty much exclusively uses +5v, so we aren't missing much by
    letting -5v go unmeasured.
    Louis,

    Computing power consumption is dynamic, you need to stress it to get an
    average overall consumption, isolating the active at the main with a
    clip on amp meter still the best way to do it.

    Shifting bits around do cost power.

    --
    Moussa

    "People alike with a similar circumstances, tend to find each
    others across space and time, given enough time in life, no
    matter distance, language, race, colour and believes" (c) MEK
    *** Do Not Copy, Duplicate or Use without my Permission ***

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)