I used to own a HP4274A but I sold it again because for it's size it couldn't do much and for measuring low resistance (milli-Ohms) it was useless. For now I'm using this one:
http://www.ebay.com/itm/Auto-LCR-Digital-Electric-Bridge-Resistance-Capacitance-Inductance-ESR-Meter-/171199475262 (http://www.ebay.com/itm/Auto-LCR-Digital-Electric-Bridge-Resistance-Capacitance-Inductance-ESR-Meter-/171199475262)
(http://i.ebayimg.com/images/g/dfYAAMXQlgtStFdS/s-l1600.jpg)but it doesn't have data logging or remote control so even though it is pretty accurate it's use is very limited.
One that interests me very much is this one because it has a reasonable frequency span, can apply DC voltages/currents and it costs around $1200 including shipping:
http://www.ebay.com/itm/Hi-accuracy-0-05-LCR-Meter-50Hz-200KHz-14K-Frequency-Points-TFT-LCD-USB-RS232-/272298505240 (http://www.ebay.com/itm/Hi-accuracy-0-05-LCR-Meter-50Hz-200KHz-14K-Frequency-Points-TFT-LCD-USB-RS232-/272298505240)
It is from a brand called ZXP (http://www.zxptest.com/eng/ (http://www.zxptest.com/eng/) ) and with some digging the English manuals can be found for similar models. There are tons of similar LCR meters on Ebay from Applent and Tonghui; I get the feeling a lot gets copied.
I used to own a HP4274A but I sold it again because for it's size it couldn't do much and for measuring low resistance (milli-Ohms) it was useless. For now I'm using this one:So, regarding the HP4274A, not taking the low resistance measurements into account, you got rid of it because it doesn't have many capabilities that new LCR meters have?
One that interests me very much is this one because it has a reasonable frequency span, can apply DC voltages/currents and it costs around $1200 including shipping:Seeing as how they are similar in price, what do you think of the capabilities of the HP 4263B versus the ZXP?
http://www.ebay.com/itm/Hi-accuracy-0-05-LCR-Meter-50Hz-200KHz-14K-Frequency-Points-TFT-LCD-USB-RS232-/272298505240 (http://www.ebay.com/itm/Hi-accuracy-0-05-LCR-Meter-50Hz-200KHz-14K-Frequency-Points-TFT-LCD-USB-RS232-/272298505240)
It is from a brand called ZXP (http://www.zxptest.com/eng/ (http://www.zxptest.com/eng/) ) and with some digging the English manuals can be found for similar models. There are tons of similar LCR meters on Ebay from Applent and Tonghui; I get the feeling a lot gets copied.
At that price tag I wouldn't hesitate to get the Applent: http://www.ebay.com/itm/Applent-AT826-USB-Handheld-LCR-Meter-100kHz-LCR-Meter-Portable-LCR-Meter-New-/261672893309?hash=item3ceceb7b7d:g:dkgAAOxyaTxTU58C (http://www.ebay.com/itm/Applent-AT826-USB-Handheld-LCR-Meter-100kHz-LCR-Meter-Portable-LCR-Meter-New-/261672893309?hash=item3ceceb7b7d:g:dkgAAOxyaTxTU58C)
I've got one of these (paid a little more than this) and didn't regret the purchase. Compact, reasonable frequency range and pretty accurate.
Cheers,
Thomas
It is nice but the number of test frequencies is very limited.I used to own a HP4274A but I sold it again because for it's size it couldn't do much and for measuring low resistance (milli-Ohms) it was useless. For now I'm using this one:So, regarding the HP4274A, not taking the low resistance measurements into account, you got rid of it because it doesn't have many capabilities that new LCR meters have?
According to the specs (14000 different test frequencies) the ZXP would allow to make a fine grained plot of Q versus frequency of a component where the 4263B can only do a few standard frequencies. In my case the 100kHz of the 4263B would not be high enough. The 4263B is also missing DC bias abilities which are handy to check the voltage dependant behaviour of high capacity MLCC capacitors.One that interests me very much is this one because it has a reasonable frequency span, can apply DC voltages/currents and it costs around $1200 including shipping:Seeing as how they are similar in price, what do you think of the capabilities of the HP 4263B versus the ZXP?
http://www.ebay.com/itm/Hi-accuracy-0-05-LCR-Meter-50Hz-200KHz-14K-Frequency-Points-TFT-LCD-USB-RS232-/272298505240 (http://www.ebay.com/itm/Hi-accuracy-0-05-LCR-Meter-50Hz-200KHz-14K-Frequency-Points-TFT-LCD-USB-RS232-/272298505240)
It is from a brand called ZXP (http://www.zxptest.com/eng/ (http://www.zxptest.com/eng/) ) and with some digging the English manuals can be found for similar models. There are tons of similar LCR meters on Ebay from Applent and Tonghui; I get the feeling a lot gets copied.
I have been using a function generator and oscilloscope to measure ESR and have made a calculator tool that let's me put in a few of the values and I get the ESR of the capacitor.
Hi,Cool stuff. Thank you for posting it.
Manual measurement using a scope and a sig-gen:
https://www.youtube.com/watch?v=74fz9iwZ_sM (https://www.youtube.com/watch?v=74fz9iwZ_sM)
--deckert
Hi guys, I have been looking at LCR meters for a while now and it is one piece of equipment that I am having a hard time pulling the trigger on. I have seen the DER EE DE-5000, the various hand held Agilent, and the full size Agilent (most likely HP as I have a somewhat limited budget) and I was wondering what is the best way to go in terms of accuracy, flexibility, data logging and longevity. I have been using a function generator and oscilloscope to measure ESR and have made a calculator tool that let's me put in a few of the values and I get the ESR of the capacitor.
I figure the full size ones are more accurate because they offer a wider frequency range to test with but I am unsure of what is actually needed and what is the best bang for the buck (I know it's probably the Der EE, but I would rather not).
I have been looking at the following models:
HP 4262A (the 4261A only goes up to 1KHz)
Agilent U1731C (Seems kind of pricey for a handheld tool that only goes up to 1KHz)
Agilent U1733C (Goes up to 100KHz, but costs around $100 more than the U1731C)
HP 4274A (5 1/2 digits, versus the ones above that are 3.5, the 4275A goes up to 10MHz but only goes down to 10KHz)
HP 4263B (Accurate, nice display, modern but it costs an arm and a leg and I would have to save up for a while to get one)
I know somebody out there knows enough about this stuff to help me out. :)
It is difficult for me to recommend anything except the DER EE DE-5000 for casual use because of its low cost. It covers the basics including measurements at 100kHz which are commonly specified.
If I wanted something better but at a significantly higher cost, I would look for a low frequency network analyser instead.
That is why I said "low frequency network analyser" instead of vector network analyser. They make special ones for testing components. Analog Devices even sells DDS ICs specifically intended for them.
It is one of those things which I have been tempted to design for myself and maybe make available.
VNAs are not designed to work at very low or very high impedances - only impedances close to that of their bridge, which is normally 50 ohms.This statement isn't quite true. There are several ways a VNA can be build and the ones with a lower frequency range (tens of Hertz or lower) have several methods of measuring which allows to measure very low and very high impedances.
Can you give me an example of such an instrument bf one of the manufacturers of high-end test equipment, such as Anritsu, Rohde &Schwarz, IET labs, Keysight, Tektronix, Keithley etc? What impedance range do they cover, and what sort of frequency range?
Can you give me an example of such an instrument bf one of the manufacturers of high-end test equipment, such as Anritsu, Rohde &Schwarz, IET labs, Keysight, Tektronix, Keithley etc? What impedance range do they cover, and what sort of frequency range?
Any such instrument must be able to measure the vector of the impedance.
I've personally never seen anything commercially available that can cover such a wide frequency range as the LCR meters, but it is not something I have looked for to be honest.
I just performed a quick literature review and did not manage to find much, but I'm sure there must be some "review papers" on the subject of impedance measurements.
Internally they are essentially a low frequency one port vector network analyser
Analog Devices makes a dedicated DDS IC (http://www.analog.com/en/products/ad5933.html) for this and even an evaluation kit (http://www.analog.com/en/products/aducm350.html#product-evaluationkit). I am a little surprise there is not a commercial produced based on the AD5933 but maybe I have just not found it yet.May have something to do with "Capable of measuring of 100 Ω to 1 kΩ with additional circuitry" (and only 1k+ as is) (and note, it is about impedance, not just resistance). It seems to get quite tricky in that 100 to 1k range, and I don't think there would be many customers for a general purpose measurement device that does not go below 100 ohm.
There are already some threads here having some talk on that DE-5000 (and 6000) stuff, and my poor memory has collected something along the lines that DER is now making the same thing, maybe it was the original manufacturer of it for IET or something, and is now selling them to sooo many different sellers. The devices seem to now come with varying changes in what components are left out and/or replaced for saving a cent or two. They seem to work ok (with some quirks) and more or less "to the specs" (at least once the user remembers to do the calibration process). Also, it has been said that the IET's DE-6000 "improvements" were quite insignificant, and definitely not worth the price difference to DER's DE-5000. Of course, now IET part of the story is just a historical note, since IET discontinued both models (and "replaced" 6000 with a huge bench box with price as "request a quote", which typically means too expensive to be shown publicly...).It is difficult for me to recommend anything except the DER EE DE-5000 for casual use because of its low cost. It covers the basics including measurements at 100kHz which are commonly specified.The DE-5000 was a product made by the reputable company IET labs. I don't have a direct link, but here
https://www.ietlabs.com/de6000-lcr-meter.html (https://www.ietlabs.com/de6000-lcr-meter.html)
it mentions the DE-6000 is an improvement on the DE-5000.
Now there are other DE-5000's around, that will no doubt claim the same specifications as the IET Labs instruments, but I suspect are probably inferior.
Analog Devices makes a dedicated DDS IC (http://www.analog.com/en/products/ad5933.html) for this and even an evaluation kit (http://www.analog.com/en/products/aducm350.html#product-evaluationkit). I am a little surprise there is not a commercial produced based on the AD5933 but maybe I have just not found it yet.
May have something to do with "Capable of measuring of 100 Ω to 1 kΩ with additional circuitry" (and only 1k+ as is) (and note, it is about impedance, not just resistance). It seems to get quite tricky in that 100 to 1k range, and I don't think there would be many customers for a general purpose measurement device that does not go below 100 ohm.
That chip seems to be aimed at special purpose devices, where its features and limitations have a better fit for the purpose, and where it is possible to tweak the circuitry to match the specific needs.
Sample 196, 9549925.860 Hz, 500 MS/s, 59948 points; 1145 cycles @ 52.4/cycle
Ch1: Sin, Cos = 1.6443, -1.5963; Mag = 4.58345, Phase = -44.15 deg.
Ch2: Sin, Cos = 0.0063, 0.0021; Mag = 0.01333, Phase = 18.06 deg.
Ch2:Ch1 = -50.73 dB @ 62.21 deg.; Z = 1.3513 +j 2.5805
Sample 197, 9660508.790 Hz, 500 MS/s, 59986 points; 1159 cycles @ 51.8/cycle
Ch1: Sin, Cos = 0.1239, 2.2847; Mag = 4.57618, Phase = 86.90 deg.
Ch2: Sin, Cos = -0.0058, 0.0035; Mag = 0.01350, Phase = 148.84 deg.
Ch2:Ch1 = -50.61 dB @ 61.94 deg.; Z = 1.3825 +j 2.6099
Sample 198, 9772372.210 Hz, 500 MS/s, 59965 points; 1172 cycles @ 51.2/cycle
Ch1: Sin, Cos = -2.2754, -0.2295; Mag = 4.57382, Phase = -174.24 deg.
Ch2: Sin, Cos = -0.0026, -0.0063; Mag = 0.01368, Phase = -112.60 deg.
Ch2:Ch1 = -50.49 dB @ 61.64 deg.; Z = 1.4156 +j 2.6388
Sample 199, 9885530.947 Hz, 500 MS/s, 59987 points; 1186 cycles @ 50.6/cycle
Ch1: Sin, Cos = 0.0164, -2.2851; Mag = 4.57037, Phase = -89.59 deg.
Ch2: Sin, Cos = 0.0061, -0.0033; Mag = 0.01385, Phase = -28.25 deg.
Ch2:Ch1 = -50.37 dB @ 61.34 deg.; Z = 1.4482 +j 2.6658
Sample 200, 10000000.000 Hz, 500 MS/s, 60000 points; 1200 cycles @ 50.0/cycle
Ch1: Sin, Cos = 1.5814, -1.6418; Mag = 4.55909, Phase = -46.07 deg.
Ch2: Sin, Cos = 0.0068, 0.0018; Mag = 0.01401, Phase = 14.97 deg.
Ch2:Ch1 = -50.25 dB @ 61.04 deg.; Z = 1.4830 +j 2.6969
DoneI just made a software Vector Network Analyzer (VNA) with my Rigol 1054Z and Siglent DS1025. It works from 1 Hz to 25 MHz and creates great plots and log files.
I haven't added the software to de-embed the probes (or done extensive calibration), but that won't take long.
For owners of other than Siglent generator - could you possibly craft RLC software for manually configured generator frequency? I don't mind to manually set my generator to 100 KHz or 1MHz so I can measure capacitor or inductor at given frequency.
SDG1025.write("C1: BSWV FRQ, %11.3f" % TestF)Some (not me) could maybe manufacture RLC add-on PCB with 1/10/100/1000 KHz generator on-board to have decent RLC meter that needs only Rigol 1054Z and your softwareAn Arduino (e.g. https://www.pjrc.com/store/teensy32.html (https://www.pjrc.com/store/teensy32.html) would work well for this. It doesn't even need good sine waves -- because the VNA only extracts the fundamental sinusoid from the signal. You could also control the Arduino over serial/USB from Python also. Because the VNA measures both the forcing function and the response, it can use nearly any signal; you just need the frequency set correctly.
I had a similar idea of using a signal generator and a scope, but mine was using just one RIGOL MSO1104ZS (this one has built-in generators), so no extra generator would be needed. Instead of a swept input I planned to use a bandwidth-limited noise signal, and also a correlaction/coherence/FFT approach to fiddle out phase and gain.
You could modify this line in the code:
QuoteSome (not me) could maybe manufacture RLC add-on PCB with 1/10/100/1000 KHz generator on-board to have decent RLC meter that needs only Rigol 1054Z and your softwareAn Arduino (e.g. https://www.pjrc.com/store/teensy32.html (https://www.pjrc.com/store/teensy32.html) would work well for this. It doesn't even need good sine waves -- because the VNA only extracts the fundamental sinusoid from the signal. you could control an Arduino over serial/USB from Python also. Because the VNA measures both the forcing function and the response, it can use nearly any signal; you just need the frequency set correctly.
Its clear that the noise technique will need some averaging.You'll need to average over N^2 measurements to improve performance by a factor of N. Rather than look for a single frequency each time, you can extract all data for a single band simultaneously (i.e. with the same set of measurements). However you won't be able to cover (e.g.) 1 Hz to 10 MHz in one band -- perhaps a band could only cover 1 decade ?
You could modify this line in the code:
It was just "two cents" about how *you* can improve your "product".QuoteQuoteSome (not me) could maybe manufacture RLC add-on PCB with 1/10/100/1000 KHz generator on-board to have decent RLC meter that needs only Rigol 1054Z and your softwareAn Arduino (e.g. https://www.pjrc.com/store/teensy32.html (https://www.pjrc.com/store/teensy32.html) would work well for this. It doesn't even need good sine waves -- because the VNA only extracts the fundamental sinusoid from the signal. you could control an Arduino over serial/USB from Python also. Because the VNA measures both the forcing function and the response, it can use nearly any signal; you just need the frequency set correctly.
Interesting.. You are not using DCT? (I did not read code and most likely will not)
Did you test using square wave? Any side by side results to confirm that "It doesn't even need good sine"?
No. Feel free to peruse the code if you are interested in the details.
Sample 124, 15848931.925 Hz, 500 MS/s, 59972 points; 1901 cycles @ 31.5/cycleI checked with a square wave (and added a -q command-line option). It's not as good as a sinusoid.
I'd like to understand how I could use a non-stop frequency sweep instead, but that would require good correlation between the expected frequency and correlation signal -- it's more math and coding than I want to do right now.
p.s. I also have a DE-5000 and am happy with it, although I wish it also had a 10 kHz test frequency.Weird, my DE-5000 does have 10 kHz. After I power it on (at default settings), a single push on 'freq' switches from 1kHz to 10kHz.
Now there are other DE-5000's around, that will no doubt claim the same specifications as the IET Labs instruments, but I suspect are probably inferior.
IET may have had tighter manufacturing requirements (no missing components, no replaced components, discard any that do not meet some specifications, etc.). DER is now free to sell them out with whatever changes they like, and even the info on this forum already indicates there are indeed units with differences. Whether those differences will make them "out of specs" or "inferior" is something I have not seen any solid information about.Now there are other DE-5000's around, that will no doubt claim the same specifications as the IET Labs instruments, but I suspect are probably inferior.How can they be inferior when they are the original. IET DE-5000 was just a rebadge of DER EE DE-5000.
DE-6000 is a tweeked DE-5000, it's the same hardware.
IET may have had tighter manufacturing requirements (no missing components, no replaced components, discard any that do not meet some specifications, etc.). DER is now free to sell them out with whatever changes they like, and even the info on this forum already indicates there are indeed units with differences. Whether those differences will make them "out of specs" or "inferior" is something I have not seen any solid information about.Now there are other DE-5000's around, that will no doubt claim the same specifications as the IET Labs instruments, but I suspect are probably inferior.How can they be inferior when they are the original. IET DE-5000 was just a rebadge of DER EE DE-5000.
DE-6000 is a tweeked DE-5000, it's the same hardware.
: De-embedding (aka Open/Short/Load or OSL) is necessary at all freqs.I intend to do this -- I just got the software in a state where it works well enough to move to those steps. In fact, while I do have nice smooth plots, I have not confirmed that they are accurate.
: Since you mentioned "with a single resistor" I'm guessing you're using the "Series-R" topology with the DUT to ground after it.Yes. I haven't determined what is the best value to use -- it will depend on the DUT. I may need de-embedding for different values; that'll depend on the accuracies I can achieve.
: Unless you're doing autoranging, and have high-sensitivity inputs, that topology is demanding on DSO dynamic range. An 8 bit DAC is going to be the limiting factor, especially at low Z's and high freqs. This is where swept FRA techniques hold the advantage.Yes, it autoranges. One nice feature of the Rigol is it has arbitrary values for the y-scale. I basically set the y V/div to make the measurement span +/- 3 divs. If the Q isn't too high and levels don't change too much between frequency steps, this works well. In fact the Rigol only uses +/- 100 counts for full screen display, so there is some over range available. Later I'll add a check for over range and rescale if needed. For the 1st frequency measurement, I do it twice -- once to get a good autorange value.
: Ground loops are a killer at low levels (read up on "braid error"). With generator and DSO inputs all ground-referenced, you're guaranteed to have it.I haven't noticed a problem -- not even 60 Hz pickup.
: It really helps to have a set of components that have been measured at various freqs on known-accurate impedance meters to compare your results to.Definitely. However I'm most interested in the general trend of the responses, I don't
Do you have any examples or photos of a fixture setup that might be suitable ?
Yes. I haven't determined what is the best value to use -- it will depend on the DUT. I may need de-embedding for different values; that'll depend on the accuracies I can achieve.
Yes, it autoranges. One nice feature of the Rigol is it has arbitrary values for the y-scale. I basically set the y V/div to make the measurement span +/- 3 divs. If the Q isn't too high and levels don't change too much between frequency steps, this works well. In fact the Rigol only uses +/- 100 counts for full screen display, so there is some over range available. Later I'll add a check for over range and rescale if needed. For the 1st frequency measurement, I do it twice -- once to get a good autorange value.
: Ground loops are a killer at low levels (read up on "braid error"). With generator and DSO inputs all ground-referenced, you're guaranteed to have it.I haven't noticed a problem -- not even 60 Hz pickup.[/quote]
: It really helps to have a set of components that have been measured at various freqs on known-accurate impedance meters to compare your results to.Definitely. However I'm most interested in the general trend of the responses, I don't
My main use will be for measuring power supply loop gain characteristics and output impedance.
Autoranging comes with its own set of problems. Now the inaccuracies from range switching is part of the equation. It puts you squarely in the territory of real LCR meters with this - various "range resistors" and receiver gain ranges, all with their own freq and level trims, to cover a wide Z range. OSL does not compensate well for this...
The are still the same meter manufactured by DER EE (not DER). I don't think they would downgrade it under their own name.While DER EE manufactured it for IET, IET could have asked for tighter quality than what DER EE is doing now. How good a reputation DER EE is wanting compared to IET?
IET did not manufacture the IET DE-5000 (or DE-6000), DER EE did.
Quote
Yes, it autoranges. One nice feature of the Rigol is it has arbitrary values for the y-scale. I basically set the y V/div to make the measurement span +/- 3 divs. If the Q isn't too high and levels don't change too much between frequency steps, this works well. In fact the Rigol only uses +/- 100 counts for full screen display, so there is some over range available. Later I'll add a check for over range and rescale if needed. For the 1st frequency measurement, I do it twice -- once to get a good autorange value.
Autoranging comes with its own set of problems. Now the inaccuracies from range switching is part of the equation. It puts you squarely in the territory of real LCR meters with this - various "range resistors" and receiver gain ranges, all with their own freq and level trims, to cover a wide Z range. OSL does not compensate well for this...
If the input shunt protection which guards the RF amplifier shorts out due to an overload, the fact that it saved the RF amplifier is irrelevant to the user.
Your SNR and dynamic range (30 dB only ?) will be horrible with a noise source and FFT. The scope doesn't have enough ADC resolution (8 bit) to remove the noise (in a reasonable time).
Hi, I have question, is new 670$ Pintek LCR-900 good choice for home use?