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Der EE DE-5000 Handheld LCR meter - short review

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  • Der EE DE-5000 Handheld LCR meter - short review

    Recently, Redhouse lent me his brand-new DE-5000 Handheld LCR meter for evaluation of its suitability for measuring guitar pickups, and asked me to present the results on the forum.

    The worry was, based on the published specifications, that the DE-5000 might misbehave wildly when presented with such a lossy inductor as a pickup, as happens with many models of handheld LCR meter. This did not turn out to be a problem, with both units showing gradually degrading accuracy when the dissipation factor (Rac divided by inductive reactance) exceeded about 20.

    This kind of gradual decline in accuracy is expected because the inductance signal becomes smaller and smaller compared to the AC resistance signal as the dissipation factor rises.

    When the dissipation factor exceeded 20, the Extech lost accuracy faster than the DE-5000 as the factor increased; this is probably due to the fact that my Extech was made ten years ago, and technology has marched on in the meantime. Current Extechs may be better. However, real pickups have far lower dissipation factors at 1 KHz, so this is not a problem in practice.

    When measuring a handful of pickups with both instruments, the instrument readings agreed to within 1%, the stated accuracy of the instruments.

    The bottom line is that for measuring guitar pickups, the DE-5000 is just as good as the Extech 380193 that has been our standard since 2004.


    Summary of differences:

    Extech measures L, C, and Rac, parallel and serial model, at 120 Hz or 1 KHz. There is only autoranging on parameter value; selection L, C, or R et al are all manual.

    DE-5000 measures L, C, Rac, and Rdc, parallel and serial model, at 100 Hz, 120 Hz, 1 KHz, 10 KHz, and 100 KHz. Ranging is almost completely automatic, which while convenient with near-ideal LCR components (like surface-mount components), is a nuisance with pickups (which are non-ideal inductors). In particular, the DE-5000 will switch from serial model to parallel model (is the R in series with the L, or in parallel with the L) above a certain dissipation level, causing gross errors when used on a pickup. However, the DE-5000 does allow one to manually set the model to serial, allowing pickups to be measured accurately.

    Note that for reasons related to the properties of LCR circuits and unrelated to the specific LCR meter in use, the 10 KHz and 100 KHz test frequencies are not useful for measuring the inductance of guitar pickups.

    Neither instrument will measure voltages or currents. The Extech feels more ruggedly built, being encased in a thick rubber boot and weighing 20% more than the DE-5000, but the DE-5000 is rugged enough for shop use.

    The DE-5000 is roughly half the cost of an Extech 380193. Both units are made in Taiwan.

  • #2
    How do the measurements compare at 120 Hz, where no pickup has significant eddy current losses?

    (The DE-5000 should not confused at that frequency, another possible reason for using it.)

    Comment


    • #3
      Red house, thanks for taking one for the team and thanks to Joe for checking it out.
      Seems to cost about $95 New Der EE de 5000 Handheld LCR Meter w TL 22 High Accuracy Measurement | eBay

      Comment


      • #4
        It's useless without attachments so get the ones you need. TL21 is alligator clips, TL22 is smd tweezers.
        Don't be a fool and get the cheap version with no attachments then have to pay shipping again for probes like I did .
        You can not use any kind of regular probes with it.
        (edit: above statement is erroneous, unit can be used for most purposes with regular probes)
        Last edited by g1; 08-30-2015, 06:03 PM.
        "Everything is better with a tube. I have a customer with an all-tube pacemaker. His heartbeat is steady, reassuring and dependable, not like a modern heartbeat. And if it goes wrong he can fix it himself. You can't do that with SMD." - Mick Bailey

        Comment


        • #5
          A few searches suggest that the Der EE DE-5000 is the OEM version of the discontinued IET Labs DE-5000.

          IET still archives the DE-5000 manual.

          The IR-to-usb module is a ~$60 option for thems that want data logging and are comfortable using Labview. The data report period is 1.2 seconds, about the same as the Extech.

          Diyaudio.com forum has a teardown, notes that the LCR and display functions reside in two chips from Cyrustek.

          Last edited by salvarsan; 08-29-2015, 09:46 PM. Reason: spelung
          When they close the gun shops, I'll know that the Texas gov't is taking the pandemic seriously.

          Comment


          • #6
            Originally posted by Mike Sulzer View Post
            How do the measurements compare at 120 Hz, where no pickup has significant eddy current losses?

            (The DE-5000 should not confused at that frequency, another possible reason for using it.)
            They compare to within a fraction of 1%, even using a 960 mH air coil that I built for tests back in 2005.

            By the way, I also tested a humbucker at 120 Hz, and there is significant eddy-current loss.

            Comment


            • #7
              Bingo. The Der EE DE-5000 looks exactly like the IET DE-5000, and the manuals are basically the same.

              I bet Der EE was IET's manufacturer, now permitted to sell direct now that IET has discontinued the unit.

              Comment


              • #8
                Originally posted by g1 View Post
                It's useless without attachments so get the ones you need. TL21 is alligator clips, TL22 is smd tweezers.
                Don't be a fool and get the cheap version with no attachments then have to pay shipping again for probes like I did .
                You can not use any kind of regular probes with it.
                While I agree that it's best to get the attachments, it is not true that the DE-5000 is otherwise useless. Standard 1/8" (4mm) banana plugs will fit just fine.

                Comment


                • #9
                  Originally posted by Joe Gwinn View Post
                  By the way, I also tested a humbucker at 120 Hz, and there is significant eddy-current loss.
                  That is very interesting. The losses at 1 KHz must be much larger. Do you have the numbers, and do you know the core material?

                  Comment


                  • #10
                    Originally posted by Joe Gwinn View Post
                    While I agree that it's best to get the attachments, it is not true that the DE-5000 is otherwise useless. Standard 1/8" (4mm) banana plugs will fit just fine.
                    Yes, implying it was totally useless was too strong a statement, sorry.
                    I thought the kelvin type shielding would make a substantial difference for your purposes, but maybe it's not so substantial?
                    I guess it will calibrate without the special attachments?
                    "Everything is better with a tube. I have a customer with an all-tube pacemaker. His heartbeat is steady, reassuring and dependable, not like a modern heartbeat. And if it goes wrong he can fix it himself. You can't do that with SMD." - Mick Bailey

                    Comment


                    • #11
                      Originally posted by Mike Sulzer View Post
                      That is very interesting. The losses at 1 KHz must be much larger. Do you have the numbers, and do you know the core material?
                      At 1 KHz: 3.861 H and 11.11 Kohm ac

                      At 120 Hz: 4.302 H and 7.57 Kohm ac

                      At DC: 7.477 Kohm (measured with a 6.5 digit DMM)

                      The unit is a traditional humbucker, with slug poles on one side, screw poles (threaded into a steel bar), and an alnico bar between the slugs and the steel bar. There are no names or numbers on the unit.

                      With an air-core coil, Rac equals Rdc pretty closely. One can verify the effect of the nearby metal by measuring the coils on bobbins before assembly of the humbucker.

                      Comment


                      • #12
                        Originally posted by g1 View Post
                        I thought the kelvin type shielding would make a substantial difference for your purposes, but maybe it's not so substantial?
                        I guess it will calibrate without the special attachments?
                        A four-wire (kelvin) connection is used to cancel out the contact and lead impedances, so that the component value may be accurately determined.

                        For pickups, lead and contact impedances are swamped by the pickup, the kelvin connection is not needed, and so ordinary banana plugs (which will short the two halves in each jack together) are OK.


                        https://en.wikipedia.org/wiki/Four-terminal_sensing

                        Comment


                        • #13
                          You are right, it is significant in the sense of a repeatable consistent effect. That ratio of dc/ac resistance at 120 HZ is at the top end of what I measure normally. The "not significant" I was thinking of is "not large enough significantly upset the measurement of the inductance (without the effect of eddy currents)". As your measurements show, the apparent inductance at 1 KHz is below that at 120 Hz, and this is always true, I think. The typical behavior is that as frequency rises from near zero, the apparent inductance rises just slightly above the true low frequency limit before falling below at somewhat below 1 KHz. The measurement at 120 is usually close enough to the limit for practical work.

                          Originally posted by Joe Gwinn View Post
                          At 1 KHz: 3.861 H and 11.11 Kohm ac

                          At 120 Hz: 4.302 H and 7.57 Kohm ac

                          At DC: 7.477 Kohm (measured with a 6.5 digit DMM)

                          The unit is a traditional humbucker, with slug poles on one side, screw poles (threaded into a steel bar), and an alnico bar between the slugs and the steel bar. There are no names or numbers on the unit.

                          With an air-core coil, Rac equals Rdc pretty closely. One can verify the effect of the nearby metal by measuring the coils on bobbins before assembly of the humbucker.

                          Comment


                          • #14
                            Originally posted by Mike Sulzer View Post
                            You are right, it is significant in the sense of a repeatable consistent effect. That ratio of dc/ac resistance at 120 HZ is at the top end of what I measure normally. The "not significant" I was thinking of is "not large enough significantly upset the measurement of the inductance (without the effect of eddy currents)". As your measurements show, the apparent inductance at 1 KHz is below that at 120 Hz, and this is always true, I think. The typical behavior is that as frequency rises from near zero, the apparent inductance rises just slightly above the true low frequency limit before falling below at somewhat below 1 KHz. The measurement at 120 is usually close enough to the limit for practical work.
                            It's certainly true that comparing measurements made at 1 KHz and at 120 Hz will allow one to estimate the magnitude of eddy-current loading, even if 120 Hz still has some eddy-current loading.

                            Physically, the better metric of eddy-current loading is the difference Rac (taken at various test frequencies) minus Rdc (the copper wire). This excess resistance (of Rac compared to Rdc) is largely the eddy-current effect, exclusive of everything else.

                            The behavior of inductance as a function of test frequency is dominated by the physical shape of the metal mass causing the eddy-current loading. If the metal is laminated (or ground to dust in epoxy), the loading is reduced and the inductance rises.

                            The electrical resistivity and magnetic permeability of the metal also matters.
                            Last edited by Joe Gwinn; 08-30-2015, 03:24 PM.

                            Comment


                            • #15
                              Principles of Operation of Extech and Der EE and IET LCR Meters

                              Given the clue that the DE-5000 was a discontinued IET product, in turn having originally been a GenRad (General Radio) product, I did a little digging and uncovered the founding patents:

                              US 4,196,475 and 4,181,949, both to Henry P Hall of Concord MA.

                              Edit: The better explanation in in US 4,342,089.


                              Benchtop LCR meters from GenRad are somewhat more complex, but the basic principle is the same. The block diagrams are given in the operating manuals on the benchtop units currently sold by IET.

                              For instance IET model 1693 (see chapter 4): http://www.ietlabs.com/pdf/Manuals/1693_im.pdf
                              Last edited by Joe Gwinn; 08-30-2015, 05:21 PM.

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