Cap Testing With Insufficient Tester

Collapse
X
Collapse
 
  • Page of 1
  • Time
  • Show
Clear All
new posts
Previous template Next
  • FAT
    New Member
    • May 2017
    • 5
    • usa
    #1

    Cap Testing With Insufficient Tester

    hi

    im needing to test a 4700uf capacitor and my tester only goes up 20mf. is there a way to test it with this meter.

    thanx
    fat
    Tags: None
    • FAT
      New Member
      • May 2017
      • 5
      • usa
      #2
      Re: Cap Testing With Insufficient Tester

      hahaha. oops. i meant 47000... but i opened the amp again and the cap is 4700uf. so now i mean delete post
      Last edited by FAT; 05-26-2017, 10:42 PM.

        Comment

        • mariushm
          Badcaps Legend
          • May 2011
          • 3799
          #3
          Re: Cap Testing With Insufficient Tester

          The capacitance doesn't tell you anything about how good a capacitor is. In some cases, failing capacitors can even have higher capacitance when measured while in reality.

          You can measure big capacitances using a simple resistor and a multimeter and a timer.

          See http://www.pcbheaven.com/opendir/ind...1560rud8c5dab3

          Get a power supply that has a reasonably stable voltage which is lower than the capacitor's maximum rating. Use a resistor to limit the charge rate of the capacitor .. use maybe 100 kohm or even higher.

          Put the multimeter across the capacitor and start the timer as soon as you turn on the power supply, and stop the timer when the voltage on capacitor reaches 63.2% of the power supply's voltage.

          That time in seconds is equal to R x C so your C would be t/R (Farads)


          If the capacitor charges too fast, increase the resistor value to slow the charge.

            Comment

            Previous template Next

            Related Topics

            Collapse
            • sam_sam_sam
              FNIRSI HRM-10 Internal Resistance Detector AC Lead Acid Lithium Battery Tester Review on some testing of device
              by sam_sam_sam
              https://www.ebay.com/itm/405035016711

              I got this device yesterday and did some testing on some tabbing and some incandescent light bulbs and it seems to work very well from what I can tell but how do I know how accurate the m-ohms section is what can I use to verify it accurately I also tested some li-ion battery cells and this seems to be fairly accurate because I have another tester and they seem to agree with each other

              I also checked some capacitors with it that were brand new and seem to show about what I expected to see with my blue capacitor tester so I think it...
              04-13-2025, 08:17 PM
            • DeanWy
              WD Sentinel DS5100 (NAS) boot issues
              by DeanWy
              Hi all,

              I have a Western Digital Sentinel DS5100 NAS system which has stopped working. It has dual BIOS. I bought the system second hand with an already broken primary BIOS (it rebooted multiple times until second BIOS was used).

              It worked until recently. The system was idle in Windows Server 2012 and a BSOD occurred, I think it was 'critical process died'. Thereafter it didn't boot, it just sat there with no video output and fan speed at 100% (there's a proprietary Windows driver by WD which controls the fan, outside of that it always runs at 100%).

              There...
              07-30-2024, 04:13 AM
            • Lifeisfun
              Trying to troubleshoot DDR4 SODIMM slot with slot tester
              by Lifeisfun
              Hi folks!
              I have some kind of memory problem on Lenovo laptop. I was initially able to install windows after several tries since the laptop did freeze in middle of those attempts.
              Eventually I discovered that it was related to moving the laptop.
              Later on it even stopped booting unless I pressed around the memory slot. (no keyboard LEDs only power button responds)
              If I remove the RAM I get the beeps that RAM is missing. Inserting the RAM there is silence and it will not boot most of the time. No picture.

              I removed the board got one of those memory slot testers...
              06-04-2025, 02:26 PM
            • spleenharvester
              Reverse engineering of 18650 4-channel tester
              by spleenharvester
              Hi friends

              I have reverse engineered this tester, schematic is attached and is complete except for capacitor values. These testers annoyingly have no model number but they are the ones you find on the first page of just about any website if you type in "18650 4-channel tester". There is also a 2-channel variant and a newer 8-channel variant. They are very cheap (about £15) and can measure voltage, current, internal resistance and capacity. They have a multicolour display for all these statistics. They also have terminal blocks so that if you want to use a breakout board...
              05-04-2025, 02:43 AM
            • sam_sam_sam
              EBC-X 8-Channels 18650 Battery Capacity Tester Charge & Discharge 10A Aging Test Modificatio
              by sam_sam_sam
              This is another battery testing machine that needs to be modified for the cooling fans because these are noisy but not as bad as one of the other battery testing machines that I had modified recently because of it being too noisy

              The battery testing machine is going to get two temperatures controlled cooling fans like one I put in the other battery testing machine I just have to remove the temperature sensor and relocate the temperature sensor to one of the heat sinks and put one on the other heat sink so the fan speed can be controlled by temperature

              https://www.eb...
              05-05-2024, 06:07 PM
            • Loading...
            • No more items.
            Working...