Cap rated voltage

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • nian28
    New Member
    • Feb 2009
    • 5

    #1

    Cap rated voltage

    Hi Guys,

    How do you test for the capacitor's rated voltage?
  • PCBONEZ
    Grumpy Old Fart
    • Aug 2005
    • 10661
    • USA

    #2
    Re: Cap rated voltage

    You look it up in the data table.
    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

    • nian28
      New Member
      • Feb 2009
      • 5

      #3
      Re: Cap rated voltage

      I mean, a means for you to check if the cap is in tune with the data table.

      For example, I have a 47uF/50V cap. Can I hook the cap directly to a 50V DC power supply and measure if the capacitance is not changing? Is the way I measure capacitance acceptable? If the capacitance remain unchange, can I say that the cap is in tune with the datasheet?

      Comment

      • PCBONEZ
        Grumpy Old Fart
        • Aug 2005
        • 10661
        • USA

        #4
        Re: Cap rated voltage

        If you try to measure capacitance with 50 volts on the cap you will blow up the capacitance meter.
        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

        • PCBONEZ
          Grumpy Old Fart
          • Aug 2005
          • 10661
          • USA

          #5
          Re: Cap rated voltage

          What you are trying to do won't show you or accomplish anything.

          50v rated caps are created by applying somewhere around 100v DC to them for so many hours to build up ["Form"] an aluminum oxide layer on the foil which is the actual dielectric in lytic caps.
          The process is called "forming".
          Once they are formed they are 'derated' to the rating in the data table.
          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

          • sofTest
            Badcaps Veteran
            • Aug 2008
            • 361

            #6
            Re: Cap rated voltage

            Isn't is possible to go through a reconditioning procedure to check the rated voltage? I came across a couple of sites some weeks ago where this procedure was described, though different. For low voltage capacitors, one used 1000 ohms limiting resistor for each capacitor in series with a power source. One site said to use 110% rated voltage for 3 hours, the other site said use rated voltage for 30 minutes, and then measure voltage after disconnecting. If I remember correctly, then if capacitor within 95% of rated voltage, it pass test. I realize the procedure is a bit cumbersome/impractical just to test individual capacitors, but I'm just curious myself.
            ------------
            Be a mensch

            Comment

            • nian28
              New Member
              • Feb 2009
              • 5

              #7
              Re: Cap rated voltage

              Thank you very much sofTest! I think that's the answer I was looking for.

              I was googling and had no luck finding that website, I was hoping you could post it here.

              Comment

              • sofTest
                Badcaps Veteran
                • Aug 2008
                • 361

                #8
                Re: Cap rated voltage

                Had to Google them again, but luckily the two links was still marked as read:
                http://www.duracap.com/electrolytic_...tion_guide.htm


                And two more I stumbled upon looking for the others:

                ------------
                Be a mensch

                Comment

                Related Topics

                Collapse

                • Perry Babin
                  Operating caps well below rated voltage
                  by Perry Babin
                  I think this has been answered but I couldn't find the thread.

                  Someone asked me if it would harm a capacitor (10F [not a typo], 24v) if it was operated on nothing more than 12v.

                  So, I ask... Does it change any of the capacitor's characteristics/parameters/? in any way if it is never operated near rated voltage?

                  If operated for years at 1/2 rated voltage, does it accept full rated voltage like it would if it had always been operated at the higher voltage?

                  Or would it require reforming?
                  05-23-2024, 05:43 PM
                • Antonynl
                  Capacitance and voltage of tantalum?
                  by Antonynl
                  I have a tantalum capacitors with indicators EB 21 that measures only 22pF. See attached picture.

                  Since this is a windmeter that is normally in a very high mast I would like to get the correct replacement capacitor.

                  Is there somebody that can tell me what the capacitance and voltage of this capacitor are?

                  I don't feel confident that I can figure this out myself after searching around

                  Cheers!!
                  04-14-2024, 03:19 PM
                • Fernon@Repair
                  Gigabyte Z490 Gaming X Motherboard No VCORE Voltage
                  by Fernon@Repair
                  i have Gigabyte Z490 Gaming X Motherboard .it has a power on no display fault .. no vcore voltage and debug led stuck CPU LED .

                  VCCIO voltage ok
                  VCCSA Voltage OK
                  VCCPLL Voltage OK
                  Ram Voltage ok
                  RamVTT OK
                  VPP 2.5 OK

                  But No Core Voltage

                  and i want to this vrm ic datasheet or pinout (ISL69269)
                  anyone have this ic pinout voltages?...
                  06-25-2025, 07:19 AM
                • sam_sam_sam
                  Trip light 2400 watt line conditioner bought used issue with low voltage oscillation going on between relays
                  by sam_sam_sam
                  I found two capacitors on the board and one of the leads on one capacitor had bad soldering joint and the other joint connections not much better and there were several soldering joints that way to much flux around the joint redid several of them

                  The capacitors were a non brand that I did not recognize they got replaced and now it does not oscillating between relay but what concerns me a little bit is when the voltage is a little bit low the output voltage is around 130 volts and then drops down to 115 volts this happens around 105 to 108 volts if remember correctly

                  Now...
                  06-09-2024, 10:57 AM
                • Document Archive
                  ISL95831HRTZ ISL95831HRTZ-T ISL95831IRTZ ISL95831IRTZ-T Voltage Regulator Datasheet
                  by Document Archive
                  3+1 Voltage Regulator for IMVP-7/VR12 CPUs

                  Compliant with IMVP-7/VR12, the ISL95831 provides a complete solution for microprocessor and graphic processor
                  core power supply. It provides two Voltage Regulators (VRs) with three integrated gate drivers. The first VR can be
                  configured as 3-, 2- or 1-phase VR while the second output is 1- phase VR, providing maximum flexibility. The two VRs share the
                  serial control bus to communicate with the CPU and achieve lower cost and smaller board area compared with the two chip approach.
                  Based on Intersil's Robust Ripple Regulator...
                  11-05-2024, 03:24 PM
                • Loading...
                • No more items.
                Working...