UPS Voltage?

Discussion in 'Electronic Equipment' started by BadNight, Mar 21, 2009.

  1. BadNight

    BadNight Guest

    I just bought a digital multimeter and wanted to check my battery and UPS.
    When I check the voltage of my battery it gives 12.6. When I check voltage
    of UPS ( not connected to the battery) it gives 9.7??? Shouldn't it be
    higher than 12.6 for charging to take place or does it get higher when I
    connect it to the battery?? When I check the voltage when Battery is
    connected to UPS it gives 12.7 . The UPS is working fine otherwise. The
    automatic charging red light is on when it should be charging and after some
    time the blue light (charging full) turns on so every thing looks ok.
     
    BadNight, Mar 21, 2009
    #1
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  2. BadNight

    Gerard Bok Guest

    On Sat, 21 Mar 2009 17:50:05 +0500, "BadNight"
    <> wrote:

    >I just bought a digital multimeter and wanted to check my battery and UPS.
    >When I check the voltage of my battery it gives 12.6. When I check voltage
    >of UPS ( not connected to the battery) it gives 9.7??? Shouldn't it be
    >higher than 12.6 for charging to take place or does it get higher when I
    >connect it to the battery?? When I check the voltage when Battery is
    >connected to UPS it gives 12.7 . The UPS is working fine otherwise. The
    >automatic charging red light is on when it should be charging and after some
    >time the blue light (charging full) turns on so every thing looks ok.


    You are probably looking at a smart charger.
    It detects that there is no chargable battery connected, so it
    doesn't charge anything.

    --
    Kind regards,
    Gerard Bok
     
    Gerard Bok, Mar 21, 2009
    #2
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  3. BadNight

    Rich Webb Guest

    On Sat, 21 Mar 2009 17:50:05 +0500, "BadNight" <>
    wrote:

    >I just bought a digital multimeter and wanted to check my battery and UPS.
    >When I check the voltage of my battery it gives 12.6. When I check voltage
    >of UPS ( not connected to the battery) it gives 9.7??? Shouldn't it be
    >higher than 12.6 for charging to take place or does it get higher when I
    >connect it to the battery?? When I check the voltage when Battery is
    >connected to UPS it gives 12.7 . The UPS is working fine otherwise. The
    >automatic charging red light is on when it should be charging and after some
    >time the blue light (charging full) turns on so every thing looks ok.


    [Follow-up set to s.e.b]

    Here's a guess but perhaps you're reading the RMS voltage out of the
    charger. If so, the peak voltage would be about 13.7 volts, a reasonable
    value for an unregulated trickle charge.

    --
    Rich Webb Norfolk, VA
     
    Rich Webb, Mar 21, 2009
    #3
  4. BadNight

    stan Guest

    On Mar 21, 11:37 am, "Kalarama" <> wrote:
    > "BadNight" <> wrote in message
    >
    > news:gq2nq0$vdv$...
    >
    > >I just bought a digital multimeter and wanted to check my battery and UPS.
    > >When I check the voltage of my battery it gives 12.6. When I check voltage
    > >of UPS ( not connected to the battery) it gives 9.7??? Shouldn't it be
    > >higher than 12.6 for charging to take place or does it get higher when I
    > >connect it to the battery?? When I check the voltage when Battery is
    > >connected to UPS it gives 12.7 . The UPS is working fine otherwise. The
    > >automatic charging red light is on when it should be charging and after
    > >some time the blue light (charging full) turns on so every thing looks ok.

    >
    > When you're testing a battery's condition with a digital meter, it's bestto
    > load the battery down somewhat, because (thanks to the superduper-high input
    > resistance of your meter) it can sometimes show a full, healthy voltage on
    > even a near-dead battery.
    >
    > I use an old 50 watt 8 ohm resistor.


    Sounds like he is connecting a DC reading meter across the output of
    the charger circuit without knowing the output waveform and/or with
    the battery disconnected. Doesn't mean a thing. If wishing to test the
    charger alone (disconnected) could try a fairly big capacitor and try
    and read the voltage; but even then may get a peak voltage; not
    rectified RMS or true DC voltage!! A resistive load would be better to
    get an average? Suggest a little reading about AC and DC electricity.
     
    stan, Mar 22, 2009
    #4
  5. BadNight

    Guest

    On Mar 21, 5:50 am, "BadNight" <> wrote:
    > I just bought a digital multimeter and wanted to check my battery and UPS..
    > When I check the voltage of my battery it gives 12.6. When I check voltage
    > of UPS ( not connected to the battery) it gives 9.7??? Shouldn't it be
    > higher than 12.6 for charging to take place or does it get higher when I
    > connect it to the battery?? When I check the voltage when Battery is
    > connected to UPS it gives 12.7 . The UPS is working fine otherwise. The
    > automatic charging red light is on when it should be charging and after some
    > time the blue light (charging full) turns on so every thing looks ok.


    Your UPS (Universal Power Source) is used to regulate your output
    voltage so that it remains constant. It's possible that your battery
    is just too weak(worn out) to uphold the 12.6 volts required to run
    your unit. Batteries are a lot cheaper than the whole UPS so you might
    want to weigh the cost factor in replacing the battery.

    Mr. Rick
     
    , Mar 23, 2009
    #5
  6. BadNight

    1PW Guest

    On 03/23/2009 10:40 AM, sent:

    >
    > Your UPS (Universal Power Source) is used to regulate your output

    ^^^^^^^^^

    <http://en.wikipedia.org/wiki/Uninterruptible_power_supply>

    > voltage so that it remains constant. It's possible that your battery
    > is just too weak(worn out) to uphold the 12.6 volts required to run
    > your unit. Batteries are a lot cheaper than the whole UPS so you might
    > want to weigh the cost factor in replacing the battery.
    >
    > Mr. Rick


    The OP writes that the UPS is working OK. All the observations seem to
    indicate a properly working UPS. If the OP tests the UPS by
    interrupting the A.C. input source and the UPS properly supplies a
    proper load for the approximate rated time period, then everything is OK.

    Pete
    --
    1PW @?6A62?FEH9:DE=6o2@=]4@> [r4o7t]
     
    1PW, Mar 23, 2009
    #6
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