Hameg HM8118 or a Chinese EUCOL LCR meter for a newbie? - Page 1
Forum section: electronics / testgear

author: harmitonkana
author_rank: Newbie
timestamp: February 21, 2021, 09:22:56 pm
content: Hi,I have been interested in obtaining a bench LCR meter for my hobby home lab. I'd like to use the meter for designing filters, sensors and possibly try to characterize piezo plates. I know for the last use case an impedance analyzer would be better fit but alsoa bitquite far out of my price range. At this point I need to admit that I do not fully understand LCR meters but that is also part of my motivation to get one, to learn to use one.I managed to find a refurbished Hameg (Rohde & Schwarz) HM8118 for a fair price and have one coming my way as I type. Overall I got a good impression on the device and it supports an optional test fixture for measuring transformer turns ratio and mutual inductance, which I consider a big plus.I thought I had searched for LCR meters pretty thoroughly before ordering the HM8118 but obviously not as only today I became aware of EUCOL branded affordable LCR meters. Linkhere!Does anybody here have experience on these? There seems to be 100 kHz, 200 kHz, 300 kHz, 500 kHz, 1 MHz and 2 MHz models available.My question is, what's the catch here? Sure Hameg is one of the well known brands that make high end equipment but looking at the specs of the EUCOL LCR meters their performance seems at least on par with the HM8118 and for the most part even better. Looking at the prices on AliExpress the EUCOL meters sell for roughly half the price of refurbished Hamegs.I am especially intrigued by the small frequency steps that some of the EUCOL meters offer vs. 69 preset test frequencies of HM8118 as they seem to be pretty good for performing frequency sweeps (and maybe finding the resonance frequencies of piezo plates).Here are my pluses and minuses for both of the meters:Hameg (Rohde & Schwarz) HM8118Pros: Well known quality brand, good performance, good documentation with examples on how to use the device, supports transformer testing, better resell valueCons: Expensive for the specs, "Only" 69 frequency stepsEUCOL LCR meter (U2832 for example)Pros: Good performance on paper, affordable, 10 mHz frequency resolution!Cons: Unknown everything; can't find reviews, unknown user interface & experience, most likely limited (or non-existent) support as it's a chinese product sold on AliExpress.Here are more links for the devices:AliExpress listing for EUCOL U2832HM8118 spec sheet (PDF)Again I'm a newbie on using LCR meters so I might be missing something obvious here. What do you think, should I keep the HM8118 when it arrives or get a EUCOL LCR meter instead?Thank you for your input.

author: nctnico
author_rank: Super Contributor
timestamp: February 21, 2021, 10:14:53 pm
content: Did you look at the Nano VNA? This does impedance analysis from 50kHz. Don't expect great performance at this low frequency but I think it will be better suited compared to an LCR meter. I recently bought a Nano VNA and it works quite nicely.LCR meters are nice for very precise measurements of passive components but at higher frequencies the measurement gets influenced a lot by your test setup. If your application is testing filters then a VNA is a better choice to look at impedance, frequency and phase graphs.

author: rf-loop
author_rank: Super Contributor
timestamp: February 22, 2021, 02:54:32 am
content: Quote from: harmitonkana on February 21, 2021, 09:22:56 pmTuo EUCOL U2832 on jokseenkin varmasti Tonghui 2832 tai sitten ulkoisesti samalta vaikuttava kopio.Tonghui on ihan ok valmistajakunhan hankkii aitoja.Tonghui on ihan oikeasti laatuvalmistaja varsinkin kun katsotaan hiukan arvokkaampia malleja. Mutta ei nuo monetkaan Tonghuin tuotantolinjatesterit ja muut ammattilaisten laitteet harrastajia juuri puhuttele siksi nimikin on aika vähän tunnettu "mikä lie kiinalainen".I'm quite sure this is rebranded Tonghui but in bad case it is copycat because genuine Tonghui is really higher quality brand in China and of course then copycats - lot of. If it is rebranded original Tonghui no problem but if it is copycat with other name, it can be what ever, all is not what looks outside. You know...Tonghui is imho most reliable and good Chinese manufacturer when we go to professional grade LCR test instruments. It make also other instruments and target sector is professional users.One example: Tonghui TH2832 in AliTongui web sides (as most chinese web sides they are terrible when western people look these)http://www.tonghui.com.cn/en/index.htmlAnnd then bit higher class impedance analyzer 20Hz -10MHz TH2839http://www.tonghui.com.cn/en/product_839.htmlI have not any kind of relation with Tonghui.Just only suddenly know this company. In my homeland, time ago I have owned one Tonghui LCR tester and it was better than good. It was designed to some product line for automatic test systems but can use also as just stand alone. Just like this TH2832 also is but it was in rack size metal case.

author: harmitonkana
author_rank: Newbie
timestamp: February 22, 2021, 06:27:26 pm
content: Quote from: nctnico on February 21, 2021, 10:14:53 pmI have been eyeing on the Nano VNA and it seems like a wonderful piece of kit but I haven't yet totally convinced myself on getting one. I mostly do lower frequency stuff for which a VNA might not be the most suitable thing. I read that because of the input impedance, there might be significant error if I would use a VNA for measuring unknown impedances which are far from 50 Ohms. Given the low price I might end up getting one anyway at some point just to educate myself on how to use one! Maybe impedance matching for pcb trace antennas?Quote from: rf-loop on February 22, 2021, 02:54:32 amGood catch! I thought I saw a similar looking device/enclosure somewhere but couldn't find it anymore. Thanks for sharing your experience. Very valuable to get some real user experience. I'll take a closer look on the Tonghui selection.Kiitos!I managed to find some affordable low frequency impedance analyzers (ZX70AX-200k, etc.), mostly on ebay but it's the same thing with these.. No idea how they perform in real world. Can't really tell who is the manufacturer either. They seem to be advertized mostly for ultrasonic piezo characterization. I wonder if the firmware is specifically for this very purpose or could they be used for other impedance analyzing tasks as well.Ebay link hereI will most likely return the HM8118 to the shop and see if the idea of what I really need from the device materializes more in my head.

author: poba53
author_rank: Newbie
timestamp: February 23, 2021, 01:27:37 am
content: Hi, I have the Hameg R&S HM8118 LCR meter and that is good for passive components. I used it for measuring LCR parameters vs frequency up to 200kHz (but you cant sweep the frequency) and running in climate chambers and the influence of capacitance as a function of working voltage up to 40V with external voltage source. Many ceramic materials has a huge shift vs the voltage applied that is important for switched applications. For inductive components the range of applied current is to small to be practical if you want to see the saturating behavior. I also have all adapters for different packages.

author: rf-loop
author_rank: Super Contributor
timestamp: February 23, 2021, 04:34:51 am
content: Quote from: harmitonkana on February 22, 2021, 06:27:26 pmNow it is quite clear what is this EUCOL. I did here some small "Sherlock Holmes" because I am also finding LCR meter.It is other company and nothing to with Tonghui. Except... they just copycat Tonghui, in everything. When I ask them, they directly told they make instruments what have same performance with Tonghui but lower prices.Naturally, without own development and design it is more cheap...But of course Tonghui is not alone if talk Chinese bit better testers.One perhaps not bad manufacturer is ZXP.http://zxptest.com/m/product/29_132They make some test instruments also example for aviation etc.

author: Calvin
author_rank: Regular Contributor
timestamp: February 23, 2021, 04:45:26 am
content: Hi,You may have a look at Sourcetronic.com for a european source of these Eucol/Tonghui style devices.regardsCalvin

author: rf-loop
author_rank: Super Contributor
timestamp: February 23, 2021, 05:52:16 am
content: Quote from: Calvin on February 23, 2021, 04:45:26 amExample Sourcetronic ST2839 is perfectly as Tonghui 2839 copy except front panel brand sticker. It can be copycat or real Tonghui just rebranded. If it is made by Tonghui and rebranded I can buy it if I need, but as long as it is unknown Chinese possible copycat manufacturer, no way.

author: harmitonkana
author_rank: Newbie
timestamp: February 23, 2021, 12:42:30 pm
content: Quote from: poba53 on February 23, 2021, 01:27:37 amThank you for this information. Good to hear some usage experience of the HM8118 too. Will the applied external voltage act as offset for the excitation signal or is it more about making it possible to use much larger peak to peak voltage? Indeed the HM8118 seems to be very suitable for measuring capacitors, inductors. I like the accuracy too. I have once had the chance to use HM8118 for some very basic measurements and it was able to measure singular picofarads just fine. The thing with the lesser known brand LCR meters is that even though the spec sheet shows that the display accuracy for, for example capacitors, is in the order of 0.00001pF, it might just as the name suggests, accuracy on the display, not how accurately the device is able to measure. Of course with this low capacitances the leads have a big effect too. With HM8118 I trust their claims on the devices performance. I keep thinking about the transformer test fixture too as it seems very useful for reverse engineering small transformers. How has the frequency range been for you? I understand the frequencies are probably selected to match with test frequencies specified by component manufacturers. I think jf HM8118 would be able to do real frequency sweeps with greater resolution it would serve me quite well. I found a program that someone had made to control HM8118 remotely from PC and that allows the user to sweep through the predefined frequencies but the steps are just too large to my liking.Quote from: rf-loop on February 23, 2021, 04:34:51 amThe impedance analyzers by ZXP seem quite interesting. They are in the same price range as refurbished HM8118 but allow frequency sweeps with nice steps sizes. The X-models seem to come with "LCR function" too. I can't really find more info on the LCR function but I would assume it is able to view inductance, capacitance and resistance too along with the impedance. I don't feel like I trust the usage experience of the PC software at all (all in Chinese?) so I'd prefer to be able to do as much analysis on the analyzer itself. I'd also like to know whether they offer description on the communication protocol. I'll probably make a list of questions and shoot them an email to feel how they respond.The Tonghui impedance analyzers -seem- very capable. Also outside my price range.Nice to be aware of them however. Suddenly there seems to be much more offering than I initially found. It might be that a performant impedance analyzer under 2-3k price range is just too of a tall order in this point in time.Btw, I wonder would a LCR meter with small frequency steps allow similar kind of measurements to impedance analyzers, just without a visual graph on the device itself? It seems that even though some of the LCR meters have 10mHz frequency steps they still don't allow to scan through the whole operating range at once. Only limited number of steps (in the order of hundred steps?) per scan. Just thinking out loud..Quote from: Calvin on February 23, 2021, 04:45:26 amThanks for the tip! Nice to see an european dealer as well. The prices are a tad higher though, understandably.Apologies for the people reading this topic, my mind is starting to derail into impedance analyzers.

author: Kean
author_rank: Unknown
timestamp: February 23, 2021, 02:24:28 pm
content: @rf-loop or others... Have you come across CKT brand LCR meters? CKT = Changzhou Chuangkai Electronic Co., Ltd.A couple of years ago I decided to invest in an benchtop LCR meter with SMT test fixture. I was looking at the TH2827C LCR meter which can measure to 1MHz. When chatting to my AliExpress seller, they suggested the cheaper CKT1000, and I ended up buying the CKT5000 for less than the TH2827C. It can measure at up to 5MHz, not that I've tried to do so.I haven't actually used the LCR meter as much as I expected, but it has generally met my expectations. I usually just make quick measurements with my handheld Atlas or Tonghui meters, and only rarely want to run a sweep. I just wonder how it compares to a Tonghui unit considering the price difference.The AliExpress seller I bought from appears to have close ties to CKT, but also sells Tonghui equipment and a few other brands. I have some Tonghui AC & DC power supplies, and some other gear that is rebranded Tonghui (e.g BK2831E = TH1941).