Capacitor replacement

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • debugtimog
    Member
    • Jul 2018
    • 30
    • Malaysia

    #1

    Capacitor replacement

    Hi,
    I am trying to replace a defective capacitor the one on the left side, rated 47,000uF/7.5VDC with the one on the right rated 47,000uF 10V. The question is, the size is a big difference. The other one is humungus, the size of my fist, while the other one is slightly bigger than my thumb only. I know that through the years the size of the capacitors that shrunk due to technical advancement, but this is like time 10 shrinkage? i have seen half the size shrink, but this one, the replacement is so small I am thinking something will went wrong if I go ahead with the replacement. Any advice on this? Thanks.

    Attached Files
  • Hitto
    Senior Member
    • Apr 2019
    • 95
    • Italy

    #2
    Re: Capacitor replacement

    The big one is an ancient Computer Grade Capacitor.

    The difference is that the big one handles much more current and its E.S.R. is very low.

    The replacement is general purpose, quite a cheap brand and I'd bet it would not handle more than 1/10 of the current of the big one. It will fail to smooth properly the intended current of that circuit.

    Look for some Cornell Dubilier high ripple capacitors.

    Comment

    • mariushm
      Badcaps Legend
      • May 2011
      • 3799

      #3
      Re: Capacitor replacement

      Have to agree, the small one may not be able to handle the current.

      Look into capacitors rated for higher voltage, like for example 35v..63v.. the higher volume will give them the ability to handle higher current bursts.

      Comment

      • R_J
        Badcaps Legend
        • Jun 2012
        • 9535
        • Canada

        #4
        Re: Capacitor replacement

        A similar cap CDE CGR473U7R5V3C, 47,000µf 7.5v is rated 17.8A @120Hz .
        Last edited by R_J; 07-04-2019, 10:56 AM.

        Comment

        • debugtimog
          Member
          • Jul 2018
          • 30
          • Malaysia

          #5
          Re: Capacitor replacement

          "cant handle the current" means also it will blow at some point, or it can still be used but it will not filter the ripple properly as compared to the big one?

          Comment

          • stj
            Great Sage 齊天大聖
            • Dec 2009
            • 30965
            • Albion

            #6
            Re: Capacitor replacement

            cannot handle the ripple, and will potentially damage the device because of it.

            Comment

            • PeteS in CA
              Badcaps Legend
              • Aug 2005
              • 3578
              • USA, Unsure of Planet

              #7
              Re: Capacitor replacement

              That original cap looks like a super low ESR, very high ripple current type that Sprague and maybe Mallory used to make. The ESR will be less than 10 milliohms, probably less than 5 milliohms.

              That Jackcon (a very poor brand, generally) cap would be spewing its guts, probably within minutes.
              PeteS in CA

              Power Supplies should be boring: No loud noises, no bright flashes, and no bad smells.
              ****************************
              To kill personal responsibility, initiative or success, punish it by taxing it. To encourage irresponsibility, improvidence, dependence and failure, reward it by subsidizing it.
              ****************************

              Comment

              • Stefan Payne
                Badcaps Legend
                • Dec 2009
                • 1267
                • Germany

                #8
                Re: Capacitor replacement

                What device is that picture from??

                Comment

                • eccerr0r
                  Solder Sloth
                  • Nov 2012
                  • 8689
                  • USA

                  #9
                  Re: Capacitor replacement

                  ^ yes

                  Thing is, old computers that have these really huge old low ESR caps typically have the charging side with... 120Hz rectified mains, oddly enough. Switching PSUs were rare and in order to have the hold up, large capacitances were needed. So while the discharge side is same as always (though it tends to have little small bypass caps to help that) the charge side is very easy on the capacitor.

                  That being said, and still don't know what the capacitor came out of, and it very well may be switching. So, how did you determine the cap was bad?

                  Comment

                  • PeteS in CA
                    Badcaps Legend
                    • Aug 2005
                    • 3578
                    • USA, Unsure of Planet

                    #10
                    Re: Capacitor replacement

                    Originally posted by eccerr0r
                    ^ yes

                    Thing is, old computers that have these really huge old low ESR caps typically have the charging side with... 120Hz rectified mains, oddly enough. Switching PSUs were rare and in order to have the hold up, large capacitances were needed. So while the discharge side is same as always (though it tends to have little small bypass caps to help that) the charge side is very easy on the capacitor.

                    That being said, and still don't know what the capacitor came out of, and it very well may be switching. So, how did you determine the cap was bad?
                    Boschert used a similar or that very cap for the output capacitor on their HL1500, a 5V, 300A, 1500W switching power supply. I do not know whether Boschert ever brought that model to market, though.

                    The capacitor in the picture has a 9121 date code, meaning it was made in the 21st week of 1991. Pioneer Magnetics is (was?) not a manufacturer of electrolytic (or any other) capacitors, but of switching power supplies.
                    Last edited by PeteS in CA; 07-08-2019, 03:39 PM.
                    PeteS in CA

                    Power Supplies should be boring: No loud noises, no bright flashes, and no bad smells.
                    ****************************
                    To kill personal responsibility, initiative or success, punish it by taxing it. To encourage irresponsibility, improvidence, dependence and failure, reward it by subsidizing it.
                    ****************************

                    Comment

                    • debugtimog
                      Member
                      • Jul 2018
                      • 30
                      • Malaysia

                      #11
                      Re: Capacitor replacement

                      The capacitor was from a power supply, it was determined to be bad using an ESR meter. Measured capacitance was 1000UF. Im planning to bank a few smaller capacitor to duplicate the big one. Advice are welcome.

                      Comment

                      Related Topics

                      Collapse

                      • artvandalai
                        Where can I get compatible capacitor for replacement?
                        by artvandalai
                        Blew the capacitor on my analytical balance scale using the wrong power adapter. I need help finding a replacement compatible capacitor to buy. Will any 100uf 40v capacitor work as a replacement?
                        12-28-2024, 10:15 AM
                      • r2digital
                        klipsch kda-500 amplifier suitable power supply capacitor replacement ?
                        by r2digital
                        I have a klipsch kda-500 that would turn on and allow me to get into the web management but it was picking up a lot of noise from audio sources so i decided to replace the smd caps on the power supply along with radial one. Some one was in here before me and they basically burned the bottom side of the traces off for the radial cap but i was able to repair it without any real problem. I thought i did a good job sourcing out replacement caps but apparently not and now i can't get the power supply to turn on it just constantly try's to keep turning on. Attached is a picture of the power supply before...
                        04-18-2024, 03:50 PM
                      • rwkish
                        Discontinued Capacitor looking for Replacement
                        by rwkish
                        Capacitor has been discontinued (EGXF101ELL331MM20S) all of the replacements I have found have are smaller than 0.709" Dia (18.00mm). I would like to use the same size or at least close to the same size Capacitor. 19mm would be too big as they would touch and not be able to through hole mount. Tia...
                        08-18-2024, 06:54 PM
                      • Hylax
                        Replacement capacitor options please?
                        by Hylax
                        Hi, I'm super new to this capacitor stuff but I've some basic soldering experience with old cellphones PCBs and headphones. I have this APAQ AR5K 820∆μF 3V Dc Capacitor from a motherboard that I'm looking to replace, photos I've attached. But I'm unable to find a 3V one like I've marked in the spec sheet in red (This is the one currently present in the motherboard). But the 6.3V one I can find (marked in blue) is of similar dimensions but different specs as mentioned in the table. Is it okay to replace it with higher voltage cap, slightly higher ESR, slightly lower ripple current, and double...
                        08-09-2024, 11:25 PM
                      • GKdays
                        Single capacitor replacement on arcade pcb
                        by GKdays
                        I have a damaged capacitor from a bootleg double dragon arcade pcb and I have the normal values from it:

                        10 volt, 100uF, 85c, but someone from an arcade forum said that the ripple current is not that critical and any good quality low esr cap would be fine, the damaged one is an electrolytic can type but I don't know what to look for as far as low esr is concerned, can a ceramic capacitor be used instead, the capacitor is going to the +5 volt

                        I don't know the brand but on the top of the capacitor is stamped "76 F6" if there is a datasheet ide be able to...
                        08-09-2022, 05:21 AM
                      • Loading...
                      • No more items.
                      Working...