Analog ESR meter design

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  • vhr
    Member
    • Aug 2012
    • 21
    • Russia

    #61
    Re: Analog ESR meter design

    ESR/L/C/F/P/t meter
    C-0,4...60000uF(and leakage)
    R/ESR-0...130Ohm
    3 ranging
    0-2(resolution 0,001)
    2-20(0,01)
    20-130(0,1)
    http://radiokot.ru/circuit/digital/measure/73/

    Comment

    • vhr
      Member
      • Aug 2012
      • 21
      • Russia

      #62
      Re: Analog ESR meter design

      http://rghost.ru/private/40994632/91...2c3d7b90daca81

      Comment

      • marcdima
        Member
        • Oct 2012
        • 10
        • Morocco

        #63
        Re: Analog ESR meter design

        Originally posted by vhr
        ESR meter for capacitor LOW ESR in circuit.
        http://radiokot.ru/konkurs/10/
        good link

        someone has tested this assembly
        really interesting but unfortunately the schema is not clear to me especially value of component
        I tried to translate the page but I do not understand much

        Comment

        • MDOC
          EngineeringTech
          • Mar 2010
          • 146
          • USA

          #64
          Re: Analog ESR meter design

          Originally posted by marcdima
          good link

          someone has tested this assembly
          really interesting but unfortunately the schema is not clear to me especially value of component
          I tried to translate the page but I do not understand much
          Download and load the Google toolbar onto the IE browser. It may work in FF. When you load the Russian page, you will be prompted on whether you want to translate the page. (If component values are in an image file, it can't be translated.)

          Red arrow points to the Google toolbar. See red circle.

          Comment

          • vhr
            Member
            • Aug 2012
            • 21
            • Russia

            #65
            Re: Analog ESR meter design

            marcdima
            Works fine.Transformers HDT of old TVs and monitors.
            Resolution-0,005Ohm.
            VT1-BC547
            VD3,VD4-1N5819
            Calibrate these resistors and capacitors.
            https://cdn.badcaps-static.com/pdfs/...3abfb7040a.pdf

            http://www.capacitorlab.com/capacitor-types-polymer/
            Last edited by vhr; 10-20-2012, 05:10 PM.

            Comment

            • marcdima
              Member
              • Oct 2012
              • 10
              • Morocco

              #66
              Re: Analog ESR meter design

              thank you MDOC I did the translation I wanted to say rather it is not well translated

              thank you vhr this is what I wanted to know
              and thank you again for useful documents

              I need just know the capacitor C2 = 6200* !!! , and I give a try . What is the value of this one ?

              Comment

              • vhr
                Member
                • Aug 2012
                • 21
                • Russia

                #67
                Re: Analog ESR meter design

                marcdima
                Of C2 and TV2 depends maximum stretching of the scale.I have a scale of 0-5 Ohms.Resolution can be increased to 0,001Ohms!Then the full scale will be 0-0,5Ohms.
                For LOW-impedance(LOW ESR)capacitors that is enough.

                Comment

                • MDOC
                  EngineeringTech
                  • Mar 2010
                  • 146
                  • USA

                  #68
                  Re: Analog ESR meter design

                  Originally posted by marcdima
                  thank you MDOC I did the translation I wanted to say rather it is not well translated
                  OK. I removed the image because it had sensitive information on it.

                  Comment

                  • Shocker
                    Banned
                    • Dec 2011
                    • 635

                    #69
                    Re: Analog ESR meter design

                    I think I figured out why constant-current meters are nonexistent.

                    With the constant-voltage design, the higher the ESR, the lower the dissipation in the cap. Remember, smaller caps have higher ESR, and worse heat dissipation.

                    The constant-current design means higher ESR caps get HOTTER. And when they're also smaller...

                    Comment

                    • marcdima
                      Member
                      • Oct 2012
                      • 10
                      • Morocco

                      #70
                      Re: Analog ESR meter design

                      thank you guys I am trying to collect components

                      Comment

                      • budm
                        Badcaps Legend
                        • Feb 2010
                        • 40746
                        • USA

                        #71
                        Re: Analog ESR meter design

                        Current through the cap will in mA or less range not enough to cause any heat.
                        IE: 10 Ohms ESR with constant current of 10mA will cause 100mV (about 1 milli-watt of power) feeding the reading circuit, which mean you can even use smaller curret source.
                        Last edited by budm; 10-22-2012, 09:04 AM.
                        Never stop learning
                        Basic LCD TV and Monitor troubleshooting guides.
                        http://www.badcaps.net/forum/showthr...956#post305956

                        Voltage Regulator (LDO) testing:
                        http://www.badcaps.net/forum/showthr...999#post300999

                        Inverter testing using old CFL:
                        http://www.badcaps.net/forum/showthr...er+testing+cfl

                        Tear down pictures : Hit the ">" Show Albums and stories" on the left side
                        http://s807.photobucket.com/user/budm/library/

                        TV Factory reset codes listing:
                        http://www.badcaps.net/forum/showthread.php?t=24809

                        Comment

                        • vhr
                          Member
                          • Aug 2012
                          • 21
                          • Russia

                          #72
                          Re: Analog ESR meter design

                          To increase the resolution reduce the resistors to 0,5-0,3Ohms.
                          You can also increase the number of turns of the secondary winding of the transformer TV2.

                          Comment

                          • tom66
                            EVs Rule
                            • Apr 2011
                            • 32560
                            • UK

                            #73
                            Re: Analog ESR meter design

                            Originally posted by Shocker
                            I think I figured out why constant-current meters are nonexistent.

                            With the constant-voltage design, the higher the ESR, the lower the dissipation in the cap. Remember, smaller caps have higher ESR, and worse heat dissipation.

                            The constant-current design means higher ESR caps get HOTTER. And when they're also smaller...

                            Not really. Most constant-current designs have a maximum compliance voltage - the point at which the current is unacceptably inaccurate. For one prototype meter I considered building, it was 1.5 ohms. Open circuit voltage was about 1Vp-p.
                            Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
                            For service manual, schematic, boardview (board view), datasheet, cad - use our search.

                            Comment

                            • Ryu.Hayabusa
                              Member
                              • Nov 2012
                              • 12
                              • Japan

                              #74
                              Re: Analog ESR meter design

                              Originally posted by Th3_uN1Qu3
                              Attached the schematic in ExpressPCB format and as a picture for those who don't want to install the software. ExpressPCB is quite a crude package but i've gotten used to it and i can't be bothered to learn anything else right now. The PCB needs some updates, it'll probably get posted when i find a suitable case for the meter, i'll have to shop around next week.
                              Is this the final design? I've been looking for a ESR meter I can build and attach to a DMM so I don't have to muck around with micros or display controllers.

                              Comment

                              • mainfurer
                                New Member
                                • Nov 2012
                                • 1
                                • mexico

                                #75
                                Re: Analog ESR meter design

                                Originally posted by Th3_uN1Qu3
                                I get zero. That was what all the trouble was about... getting it to read zero with the test leads shorted was quite an undertaking, and i learned a lot about stray coupling between wires in the meantime. There are only two test leads (woulda been awkward to use four), but with two pairs of wires going to them.

                                For checking PCB shorts you would need to change the frequency to 50Hz and increase the coupling capacitor values so the 50Hz signal passes unaltered. Much less trouble that way. PCB traces are inductive too so if using a high frequency you could have the surprise that a short does not read as such unless the probes are really close to it. Another application for an AC milliohm meter working at 50Hz is as a "ground loop buster" in troubleshooting PCB layouts.
                                HELLO!!! greets from Mexico, may i ask you for your final version of the esr add on for the dmm??? can you post please your pcb? so me and other can have a view of your impressive job thanks and hope to read from you soon

                                Comment

                                • marcdima
                                  Member
                                  • Oct 2012
                                  • 10
                                  • Morocco

                                  #76
                                  Re: Analog ESR meter design

                                  Originally posted by vhr
                                  To increase the resolution reduce the resistors to 0,5-0,3Ohms.
                                  You can also increase the number of turns of the secondary winding of the transformer TV2.
                                  Unfortunately, this link does not work now
                                  http://radiokot.ru/konkurs/10/
                                  but luckily I saved the diagram (see picture)



                                  I would really like a small explanation of this diagram
                                  I'm not a pro of electronics but I have basic notion
                                  I always learning in this field

                                  I understood
                                  In this diagram the power source is a 1.2V battery rechargeable

                                  the transistor VT1 used as a constant current source to approximately 50mA current given

                                  capacitor C2 and the transformer TV1 I think it is the oscillator

                                  The 1 ohm Bridge Resistor for the measuring
                                  I have a question here! to increase the precision we reduce the value of resistors to 0.5 ohm or less ,so it is possible to use the smd resistance of 0 ohm ? (ideal conductor is not going to be 0 Ohms when I measure these resistances 0 ohm with true rms multimeter I see 0.7 ohm )

                                  another question the transformer TV2 I think used here to amplify the signal
                                  What kind used here
                                  what is he number of turns of the primary and secondary ...?

                                  I appreciate your support my friends
                                  thank you very much

                                  Comment

                                  • Simurg
                                    New Member
                                    • Nov 2012
                                    • 1
                                    • Belarus

                                    #77
                                    Re: Analog ESR meter design

                                    link: http://radiokot.ru/circuit/analog/measure/22/
                                    forum: http://radiokot.ru/forum/viewtopic.p...60919#p1460919
                                    transformer TV1 and transformer TV2 http://lightportal.at.ua/2011/SDUanalog/Shem07.jpg
                                    Last edited by Simurg; 11-03-2012, 05:50 AM.

                                    Comment

                                    • tom66
                                      EVs Rule
                                      • Apr 2011
                                      • 32560
                                      • UK

                                      #78
                                      Re: Analog ESR meter design

                                      Originally posted by marcdima
                                      Unfortunately, this link does not work now
                                      http://radiokot.ru/konkurs/10/
                                      but luckily I saved the diagram (see picture)



                                      I would really like a small explanation of this diagram
                                      I'm not a pro of electronics but I have basic notion
                                      I always learning in this field

                                      I understood
                                      In this diagram the power source is a 1.2V battery rechargeable

                                      the transistor VT1 used as a constant current source to approximately 50mA current given

                                      capacitor C2 and the transformer TV1 I think it is the oscillator

                                      The 1 ohm Bridge Resistor for the measuring
                                      I have a question here! to increase the precision we reduce the value of resistors to 0.5 ohm or less ,so it is possible to use the smd resistance of 0 ohm ? (ideal conductor is not going to be 0 Ohms when I measure these resistances 0 ohm with true rms multimeter I see 0.7 ohm )

                                      another question the transformer TV2 I think used here to amplify the signal
                                      What kind used here
                                      what is he number of turns of the primary and secondary ...?

                                      I appreciate your support my friends
                                      thank you very much
                                      I think I understand how this works (it's very clever)

                                      The transistor is configured, with the transformer as a blocking oscillator, one of the simplest oscillators you can make, using just one transsitor. It also has a constant peak current characteristic because of this.

                                      The 1 ohm resistors are to add a voltage which the diode VD3 drops to allow low-ESR measurement. The zero function removes the rest of the offset. The resistors must be 1 ohm to allow you to measure low ESR.
                                      Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
                                      For service manual, schematic, boardview (board view), datasheet, cad - use our search.

                                      Comment

                                      • marcdima
                                        Member
                                        • Oct 2012
                                        • 10
                                        • Morocco

                                        #79
                                        Re: Analog ESR meter design

                                        thank you Simurg
                                        for the new link I see that you are the author of this great work
                                        I like the way you made the testing pads for testing the surface mounted cap. , I try to do something similair .

                                        thank you tom66 for the explanations
                                        you're right it's very clever

                                        for resistors I only found standard SMD 1R0
                                        I think tolerance will influence on the accuracy of measurement , I do not have a choice .

                                        Comment

                                        • vhr
                                          Member
                                          • Aug 2012
                                          • 21
                                          • Russia

                                          #80
                                          Re: Analog ESR meter design

                                          marcdima
                                          TV1,TV2-42TM026-RC
                                          https://cdn.badcaps-static.com/pdfs/...bddb34ce25.pdf

                                          Comment

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