Re: Testing a gel cell

Discussion in 'Electronic Repair' started by Michael Floyd, Jul 10, 2003.

  1. By your own admission you stated "For the most part, they hold some
    charge, but they don't perform as intended." If you know they are not
    performing as expected, don't waste your time worrying about testing
    them - just replace them if you want a reliable UPS. If the UPS units
    have multiple batteries, replace all of them at the same time.

    Regards,

    Michael Floyd


    On Wed, 9 Jul 2003 10:26:18 -0400, "Michael A. Covington"
    <> wrote:

    >What is the best way to test a lead-acid gel cell? We have a lot of aging
    >UPSes and we want to replace the batteries that are no longer in spec. For
    >the most part, they hold some charge, but they don't perform as intended.
    >
    >What should we measure? Voltage under a 1-amp load? Internal resistance
    >some other way?
    >
    >
     
    Michael Floyd, Jul 10, 2003
    #1
    1. Advertising

  2. Michael Floyd

    Sofie Guest

    Yes, this is EXACTLY the correct advice.
    --
    Best Regards,
    Daniel Sofie
    Electronics Supply & Repair
    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -


    "Michael Floyd" <> wrote in message
    news:3f0d92d8.154251131@news.3web.net...
    > By your own admission you stated "For the most part, they hold some
    > charge, but they don't perform as intended." If you know they are not
    > performing as expected, don't waste your time worrying about testing
    > them - just replace them if you want a reliable UPS. If the UPS units
    > have multiple batteries, replace all of them at the same time.
    >
    > Regards,
    >
    > Michael Floyd
    >
    >
    > On Wed, 9 Jul 2003 10:26:18 -0400, "Michael A. Covington"
    > <> wrote:
    >
    > >What is the best way to test a lead-acid gel cell? We have a lot of

    aging
    > >UPSes and we want to replace the batteries that are no longer in spec.

    For
    > >the most part, they hold some charge, but they don't perform as intended.
    > >
    > >What should we measure? Voltage under a 1-amp load? Internal resistance
    > >some other way?
    > >
    > >

    >
     
    Sofie, Jul 10, 2003
    #2
    1. Advertising

  3. Michael Floyd

    Andre Guest

    "Michael A. Covington" <> wrote in message news:<>...
    > "Michael Floyd" <> wrote in message
    > news:3f0d92d8.154251131@news.3web.net...
    > > By your own admission you stated "For the most part, they hold some
    > > charge, but they don't perform as intended." If you know they are not
    > > performing as expected, don't waste your time worrying about testing
    > > them - just replace them if you want a reliable UPS. If the UPS units
    > > have multiple batteries, replace all of them at the same time.

    >
    > The key words are, "For the most part." Some of the UPSes may have other
    > things wrong. That's why I want to test the batteries rather than just
    > replace them.



    August issue of Electronics World has a nice automated lead acid
    cycler . Supposedly if you charge and discharge them several times in
    the correct way (gel cells) they may recover their low internal
    resistance .

    -Andre

    Other trick . Compare the internal resistance of the gel cell with a
    new battery from the same manufacturer . If they are significantly
    different then try charge cycling . (Note - this requires exact
    control , ovedrdischarging can cause permanent damage) I have tried
    this on NiMH as well and it often works .

    I have also tried (as a last resort) discharging lead acid to zero,
    reverse charging (off a solar cell),discharging again then charging
    again the right way round . This tends to work best where the cell is
    really, really flat (like, down to <8V) .
    Don't try it on a "good" (>12V) cell , this is where you use charge
    cycling .
    Make sure to MARK the cell so you don't use it on something by mistake
    when it has the terminals reversed . (Fizzle POP)


    www.sunnythings.com (Yes we sell new batteries :) )
     
    Andre, Jul 11, 2003
    #3
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. mc

    Testing lead-acid gel cells

    mc, Mar 5, 2005, in forum: Electronic Components
    Replies:
    6
    Views:
    288
    Peter A Forbes
    Mar 13, 2005
  2. Wong Sy Ming

    12V in, gel cell out?

    Wong Sy Ming, May 26, 2004, in forum: Electronic Design
    Replies:
    10
    Views:
    810
    Tam/WB2TT
    May 29, 2004
  3. 4 V gel cell for Tek 222PS scope

    , Apr 21, 2005, in forum: Electronic Equipment
    Replies:
    0
    Views:
    1,904
  4. 4 V gel cell for Tek 222PS scope

    , Apr 21, 2005, in forum: Electronic Repair
    Replies:
    4
    Views:
    2,446
  5. mike
    Replies:
    9
    Views:
    2,201
    Phil Allison
    Jan 19, 2010
Loading...

Share This Page