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    #1

    Caps Values

    Hi,

    I am thinking of making an order of around 1K caps. These will be mixed with batches of 100 each value so 10 values.

    I know that I need low esr caps for TFT Monitors and LCD Monitors, but what about the ripple? Do I need low Ripple or High Ripple? I know that the best thing to do is to order the caps according to the bad caps values, but this is impossible for me as I need to have stock in hand.

    One last thing. Are Elite caps any good? I am asking because I replace many of them, but only after 5 - 6 years of work. Or should they last much longer?

    Thanks

    Mario
    Tags: None
    #2
    Re: Caps Values

    Always same or higher ripple.
    Elite is not a good brand!

    Comment

      #3
      Re: Caps Values

      Elite are horrible.

      Use Panasonic, Nichicon, Sanyo/Suncon, Rubycon, Chemicon
      There are some others but they don't show up often or are expensive.

      The ESR and Ripple requirements vary by what the cap does.
      You can have a 1500uF/16v with [barely]low ESR and a 1500uF/16v with [extremely]low ESR in the same screen.
      - Using a cap with higher ESR than original is BAD.
      - Using a cap with less Ripple than original is BAD.
      - Sometimes [usually] you can get away with using much lower ESR than the original but not always and when it doesn't work you could damage something else. [If there is an inductor connected to the cap then it's usually a bad idea.]
      -
      A little lower ESR is okay.
      There is no such thing as "too high" of a Ripple rating. [Think of Ripple like the "amps" rating on wire.]

      - You should match your replacements to the original specs including ESR and Ripple.

      You will soon find that 10 values isn't enough to keep you from having to order caps for every job.

      If you are dead set on only stocking 10 values then use Panasonic FM and/or FR series.
      Screens don't ~usually~ use lower ESR than those and they will work [in most cases] to replace lower grade [meaning higher ESR] caps.
      .
      Last edited by PCBONEZ; 07-03-2011, 04:45 AM.
      Mann-Made Global Warming.
      - We should be more concerned about the Intellectual Climate.
      -
      Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
      - Dr Seuss
      -
      You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
      -

      Comment

        #4
        Re: Caps Values

        A better way is to over-order slightly and keep track of your use for a while.
        -
        When you need 5 or less order 10.
        If you need more than 5 order 20 or 25.
        -
        Keep track of your use and after a while you'll know which are worth ordering in bulk for what you usually work on.
        .
        Mann-Made Global Warming.
        - We should be more concerned about the Intellectual Climate.
        -
        Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
        - Dr Seuss
        -
        You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
        -

        Comment

          #5
          Re: Caps Values

          Originally posted by Rob Northen View Post
          Always same or higher ripple.
          Elite is not a good brand!
          Thanks for your reply.

          Comment

            #6
            Re: Caps Values

            Originally posted by PCBONEZ View Post
            Elite are horrible.

            Use Panasonic, Nichicon, Sanyo/Suncon, Rubycon, Chemicon
            There are some others but they don't show up often or are expensive.

            The ESR and Ripple requirements vary by what the cap does.
            You can have a 1500uF/16v with [barely]low ESR and a 1500uF/16v with [extremely]low ESR in the same screen.
            - Using a cap with higher ESR than original is BAD.
            - Using a cap with less Ripple than original is BAD.
            - Sometimes [usually] you can get away with using much lower ESR than the original but not always and when it doesn't work you could damage something else. [If there is an inductor connected to the cap then it's usually a bad idea.]
            -
            A little lower ESR is okay.
            There is no such thing as "too high" of a Ripple rating. [Think of Ripple like the "amps" rating on wire.]

            - You should match your replacements to the original specs including ESR and Ripple.

            You will soon find that 10 values isn't enough to keep you from having to order caps for every job.

            If you are dead set on only stocking 10 values then use Panasonic FM and/or FR series.
            Screens don't ~usually~ use lower ESR than those and they will work [in most cases] to replace lower grade [meaning higher ESR] caps.
            .
            Thanks for the very detailed reply. Its great.

            I will use panasonic FM series. But dont know From where I can order in bulk. Do you know anyone selling them at a good price please?

            Comment

              #7
              Re: Caps Values

              Originally posted by mike9h29 View Post
              Thanks for the very detailed reply. Its great.

              I will use panasonic FM series. But dont know From where I can order in bulk. Do you know anyone selling them at a good price please?
              If you are in the US then Digikey and [I think] Mouser too now.

              FR is a brand new series with nearly identical specs to FM but the FR are longer life.
              If the cost difference is small then choose FR.

              .
              Mann-Made Global Warming.
              - We should be more concerned about the Intellectual Climate.
              -
              Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
              - Dr Seuss
              -
              You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
              -

              Comment

                #8
                Re: Caps Values

                Personally I'm planning on stocking up on itty bitty caps. Not for sure how much it matters, they generally don't fail visibily but in older equipment their ESR tends to drift slowly higher with age. I can't imagine this would be a good thing, especially with PWM feedback circuitry... perhaps all that is needed is to adjust a trim pot to compensate but I dunno. I figure if they are less than a quarter each, or maybe .20 cents then in most cases even if I have to replace 10-15 at one in a device to ensure correct operation of it's circuits then its money well spent.

                Not trying to steal the limelight in this thread, but whats are good substitute for miniature S5 series Teapos, miniature RMH series OST's, SS fukyoos? Most datasheets don't list impedance on cap values this low, only ripple.

                Comment

                  #9
                  Re: Caps Values

                  It's not the low value it's that they are GP caps.
                  I generally use 'entry level' low ESR caps like FC, LXZ, PW for those [to stock fewer caps] although there are probably more than a dozen other options.
                  Just make sure the ripple is good.
                  Mann-Made Global Warming.
                  - We should be more concerned about the Intellectual Climate.
                  -
                  Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
                  - Dr Seuss
                  -
                  You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
                  -

                  Comment

                    #10
                    Re: Caps Values

                    Hi Pcbonez

                    I'm curious about your comment regarding inductors connected to caps.

                    Looking at the average psu output stage, 3.3v, 5v, 5vsb, 12v each output contains an inductor or 2 followed by 1 or 2 caps.

                    I have always assumed that low esr in these areas is desirable to maximise power transfer to load. Is that really a valid case?

                    Or to put that into a question . . .
                    what specifically should one be considering, and how, in the psu output area when recapping?

                    Sal . . .

                    Comment

                      #11
                      Re: Caps Values

                      Originally posted by badcapsal View Post
                      Hi Pcbonez

                      I'm curious about your comment regarding inductors connected to caps.

                      Looking at the average psu output stage, 3.3v, 5v, 5vsb, 12v each output contains an inductor or 2 followed by 1 or 2 caps.

                      I have always assumed that low esr in these areas is desirable to maximise power transfer to load. Is that really a valid case?

                      Or to put that into a question . . .
                      what specifically should one be considering, and how, in the psu output area when recapping?

                      Sal . . .
                      To really 'get it' you have to look at what goes on with DC and AC -separately- because that's how caps behave even though everything is going on at the same time. That includes what happens with any associated inductors.
                      IOW: It will make more sense if you think like it's an AC circuit and a DC circuit happening in the same place at the same time but not mixing.

                      AC = Alternating CURRENT.
                      DC = Direct CURRENT.
                      The can co-exist in a cap but they don't really mix.
                      - People forget it's about currents and get confused by adding voltages together. That's not how it works.

                      DC current does not pass -through- the cap. [Except for a tiny bit - leakage.]
                      AC currents do pass -through- the cap. [Even though technically the electrons don't.]

                      The OP filter caps have two jobs.
                      - Pass Ripple & EMI currents to ground. [Higher frequency changes.]
                      - Smooth out DC transients. [Very slow compared to the AC components.]

                      The ESR has to do with the AC component [ripple and/or EMI] and doesn't have anything [I can think of anyway] to do with how much power gets to the load.
                      -
                      Smoothing DC transients has more to do with the uF [storage capacity] than with the ESR.

                      ESR is very high at DC and at higher frequencies but low at around 100kHz.
                      [ESR vs Frequency is a 'bathtub' curve with the low point near 100kHz.]

                      Also note, the voltage for the DC = the zero volts point for the AC Ripple and EMI. The AC is a peak-peak value.

                      ~~
                      If you dig around at jonnyguru you can find an experiment they did where they replaced PSU caps with lower ESR caps without paying any attention to the original ESR values or coils.
                      - It failed miserably. - Was confirmed with an O'scope used before and after recap.
                      PSU had much higher ripple with the new jap caps than it did with the old crap caps.
                      Not quite out of the ATX spec but almost.
                      .
                      Last edited by PCBONEZ; 07-06-2011, 10:11 PM.
                      Mann-Made Global Warming.
                      - We should be more concerned about the Intellectual Climate.
                      -
                      Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
                      - Dr Seuss
                      -
                      You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
                      -

                      Comment

                        #12
                        Re: Caps Values

                        nerd.
                        Cap Datasheet Depot: http://www.paullinebarger.net/DS/
                        ^If you have datasheets not listed PM me

                        Comment

                          #13
                          Re: Caps Values

                          Maybe so but I didn't have to ask a forum how to do something like this...
                          https://www.badcaps.net/forum/showthread.php?t=15176
                          And it wouldn't have kicked my ass.
                          .
                          Last edited by PCBONEZ; 07-06-2011, 11:16 PM.
                          Mann-Made Global Warming.
                          - We should be more concerned about the Intellectual Climate.
                          -
                          Be who you are and say what you feel, because those who mind don't matter and those who matter don't mind.
                          - Dr Seuss
                          -
                          You can teach a man to fish and feed him for life, but if he can't handle sushi you must also teach him to cook.
                          -

                          Comment

                            #14
                            Re: Caps Values

                            its a matter of XP. I think the only thing I have on you is: linux routers. yea
                            Cap Datasheet Depot: http://www.paullinebarger.net/DS/
                            ^If you have datasheets not listed PM me

                            Comment

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