DER-EE DE-5000 ESR zero measurement problem. - Page 1
Forum section: electronics / testgear

author: TA3UIS
author_rank: Contributor
timestamp: April 19, 2024, 03:38:43 pm
content: Hello everyone, I am new to the forum. It's a great forum.My problem is that the DER EE DE-5000 LCR METER I bought 3 months ago.Measures the ESR value of 3300uf and 10.000uf capacitors as ZERO.Where might the problem be? I added a few screenshots.

author: mawyatt
author_rank: Super Contributor
timestamp: April 19, 2024, 03:43:42 pm
content: Did you preform an Open and Short Calibration first?Best,

author: TA3UIS
author_rank: Contributor
timestamp: April 19, 2024, 03:44:40 pm
content: Hello, yes i dit it but nothing change.

author: mawyatt
author_rank: Super Contributor
timestamp: April 19, 2024, 03:47:23 pm
content: OK. Now add a small valued resistor under 1 ohm in series with the large value cap. Measure the resistor first to get it's value, then add in series with cap. Meter should show ESR as value of added resistor plus any ESR of actual cap.Edit: Just noted your frequency is 100Hz, try 1KHz instead.Best,

author: 4thDoctorWhoFan
author_rank: Regular Contributor
timestamp: April 19, 2024, 03:53:59 pm
content: Those very high value caps should read about 0.0.That means those caps are good. I would be worried if those caps did not measure zero.Approximately 2200uF and up should read zero ESR.They are probably actually measuring around 0.01 or 0.02.

author: TA3UIS
author_rank: Contributor
timestamp: April 19, 2024, 03:57:44 pm
content: I wonder why the DE-5000 does not show the ESR value before adding the resistor, I will test it with a series connected resistor and share the result.The cheap TC-1 LCR Meter showed the ESR value.See sample photo.

author: mawyatt
author_rank: Super Contributor
timestamp: April 19, 2024, 04:01:20 pm
content: As Dr Who noted, the resolution is only 0.1 ohms at 100Hz for ESR. Try as we suggested moving to 1KHz frequency, here the resolution for ESR is 0.01 ohms.Just checked a 1000uF at 100Hz and reading shows 0.0 ohms for ESR, then changed to 1KHz and we see 0.02 ohms.Best,

author: TA3UIS
author_rank: Contributor
timestamp: April 19, 2024, 04:08:57 pm
content: It gives no value at 1KHz.

author: TA3UIS
author_rank: Contributor
timestamp: April 19, 2024, 04:25:25 pm
content: Is there a sure way to tell if this is not a problem with the DE-5000?

author: mawyatt
author_rank: Super Contributor
timestamp: April 19, 2024, 04:27:51 pm
content: Check the manual, this 3300uF might be out of the range at 1KHz for ESR resolution of 10m ohms. We don't have anything larger than 1000uF, so limited in higher values, but don't think your LCR has an issue.This LCR meter works by applying a sinewave signal and measuring magnitude and angle of the DUT impedance, whereas the TC-1 uses a pulse technique. Generally the sinewave method is preferred for precision measurements and why the higher end LCR meters employ such.Best,

author: TA3UIS
author_rank: Contributor
timestamp: April 19, 2024, 05:21:13 pm
content: I connected 3 pieces of 1ohm parallel resistor in series to a 10,000uf capacitor. ESR measurement was successful.What would this measurement reveal?Is DE-5000 good or defective?

author: KungFuJosh
author_rank: Super Contributor
timestamp: April 19, 2024, 06:13:41 pm
content: Your meter works fine. All meters have limitations, and right now you're learning the limits of this one.The purpose of adding aknownresistance in series is so that you can subtract the difference to find your ESR. So you need to also measure your resistor(s) separately to know that value. If you add a 1ohm resistor in series with the cap, and you get 1.1ohm reading, your ESR is 0.1ohm.

author: TA3UIS
author_rank: Contributor
timestamp: April 19, 2024, 06:25:53 pm
content: Quote from: KungFuJosh on April 19, 2024, 06:13:41 pmAs far as I understand, the purpose here is to bypass the limitations of the device, right?Some kind of hack by connecting a 1ohm series resistor.

author: sonpul
author_rank: Regular Contributor
timestamp: April 19, 2024, 06:30:23 pm
content: You can view ESR in RS mode.

author: KungFuJosh
author_rank: Super Contributor
timestamp: April 19, 2024, 06:37:35 pm
content: Quote from: TA3UIS on April 19, 2024, 06:25:53 pmMore math than any hacking. As sonpul said, you can use Rs mode instead to show ESR without seeing the C at the same time.For example, in Cs a 2200µF cap shows correctly for me as 2.2mF but ESR says 0.0. In Rs mode it shows 0.02Ω. For comparison, my ST2832 shows Rs as 0.02424, so the DE5000 did fine.Thanks,Josh

author: Vachik
author_rank: Newbie
timestamp: April 19, 2024, 06:44:15 pm
content: It's not a problem DE-5000. That's how it should be. T1 is not a meter LCR!If you need additional characters (0.0хх), use the mode Rs.ESR according to specifications, it is usually given at a frequency of 100 kHz.

author: TA3UIS
author_rank: Contributor
timestamp: April 19, 2024, 06:45:08 pm
content: For ESR measurement only, it seems like a good idea to always measure with RS mode for high-capacity capacitors.

author: sonpul
author_rank: Regular Contributor
timestamp: April 19, 2024, 07:00:55 pm
content: ESRs of large electrolytic capacitor ratings are more often measured at 100-120Hz. Some Low ESR and polymer ones already have other requirements. E.t.c.

author: TA3UIS
author_rank: Contributor
timestamp: April 19, 2024, 07:11:34 pm
content: I guess everything is fine and it will be the RS mode that I need to use for high capacity capacitors.I made two measurements in RS mode at a frequency of 100Hz vs 100kHz and the results were as follows.