New TRMS Uni-T UT139C DMM is available now - Page 1
Forum section: electronics / testgear

author: Wytnucls
author_rank: Super Contributor
timestamp: July 28, 2013, 08:43:25 pm
content: The new 6000 count UT139C DMM is now coming to market. It felt pretty well built, when I handled a sample two months ago, before its official release.It seems reasonably priced too, for a TRMS meter with temperature measurement,a backlit LCD, NCV and optional clamp meter connection. It sells for about 50$ plus delivery cost on eBay (free delivery for the US).At first glance, it looks like at least one HRC fuse is accessible from the 2 AA battery compartment. It is marked as CAT III 600V.http://www.ebay.com/itm/UNI-T-UT139C-True-RMS-Digital-Multimeters-AC-DC-with-Temperature-Auto-Range-/181179994103?pt=LH_DefaultDomain_0&hash=item2a2f2b4ff7

author: edavid
author_rank: Super Contributor
timestamp: July 28, 2013, 08:50:31 pm
content: I don't get it, why would you buy this instead of a UT61E?

author: Monkeh
author_rank: Super Contributor
timestamp: July 28, 2013, 08:53:30 pm
content: Quote from: edavid on July 28, 2013, 08:50:31 pmTemperature, clamp, backlight, NCV...Counts aren't everything.

author: Wytnucls
author_rank: Super Contributor
timestamp: July 28, 2013, 09:28:39 pm
content: It also has VFC (Variable Frequency something?), Max/Min, auto power off, 3V diode test and possibly, proper input protection.The rubber holster looks like it is removable.

author: BillyD
author_rank: Regular Contributor
timestamp: July 28, 2013, 09:48:55 pm
content: Quote from: Monkeh on July 28, 2013, 08:53:30 pmwhat clamp does it have? A current clamp?

author: Lightages
author_rank: Unknown
timestamp: July 28, 2013, 09:49:20 pm
content: The VFC function is basically a low pass filter to to remove noise caused by variable frequency motors/drives. It they took input protection seriously this time this would be a nice meter for the money. If they skimped and lied bout the rating again then this would be a potential bomb ready to go off in your hand.

author: Wytnucls
author_rank: Super Contributor
timestamp: July 28, 2013, 10:04:49 pm
content: I think it is compatible with the new UT221 and UT222 clamp meters, both TRMS AC and DC.I'm not sure if they are available yet.

author: Wytnucls
author_rank: Super Contributor
timestamp: July 28, 2013, 10:26:01 pm
content: Quote from: Lightages on July 28, 2013, 09:49:20 pmThere is hope, look at the picture

author: chibiace
author_rank: Regular Contributor
timestamp: July 28, 2013, 10:55:32 pm
content: are you sure thats a clamp icon on the voltage jack.

author: Monkeh
author_rank: Super Contributor
timestamp: July 28, 2013, 11:02:08 pm
content: Quote from: chibiace on July 28, 2013, 10:55:32 pmYes. It supports an external clamp with a 60A range, 10mV/A.

author: true
author_rank: Frequent Contributor
timestamp: July 28, 2013, 11:57:22 pm
content: Quote from: Monkeh on July 28, 2013, 08:53:30 pmIf it's like the UT136 the NCV is 220V only. Need to find a manual...

author: Monkeh
author_rank: Super Contributor
timestamp: July 29, 2013, 12:13:21 am
content: Quote from: true on July 28, 2013, 11:57:22 pmNot their fault certain countries are behind the times.

author: true
author_rank: Frequent Contributor
timestamp: July 29, 2013, 12:15:11 am
content: Quote from: Monkeh on July 29, 2013, 12:13:21 amThanks for being helpful and posting the manual.The meter I keep in my work bag is sensitive starting at 24V, but does trigger below that so in addition to outlets and power cords it's handy for quick checks to see if alarm and lighting panels are powered.

author: Monkeh
author_rank: Super Contributor
timestamp: July 29, 2013, 12:15:45 am
content: Quote from: true on July 29, 2013, 12:15:11 amI'm sorry, but I don't speak Chinese. Perhaps you'd like to go have a look?I think we can reasonably expect it to be set for 230V.

author: true
author_rank: Frequent Contributor
timestamp: July 29, 2013, 12:18:41 am
content: Quote from: Monkeh on July 29, 2013, 12:15:45 amWhy? As I wrote above, it's possible to have a wider range than just line voltage. Additionally, the basic meter or stick NCV that trigger at ~100V will typically also trigger at higher voltages.

author: Monkeh
author_rank: Super Contributor
timestamp: July 29, 2013, 12:20:18 am
content: Quote from: true on July 29, 2013, 12:18:41 amTrigger at higher levels, yes, and be violently oversensitive around lower voltages and coupled voltages in countries which don't use 120V distribution.

author: true
author_rank: Frequent Contributor
timestamp: July 29, 2013, 12:32:33 am
content: I really don't know why you want to argue this so much, it's like you feel personally attacked by this or something. Over a feature to quickly check if power is present on a power line or outlet. Sorry for upsetting you so strongly over such a simple question; I didn't know there would be such animosity when the possibility of voltages lower than 230V are brought to discussions.I'll just wait for someone who buys one to post what the manual says.

author: Monkeh
author_rank: Super Contributor
timestamp: July 29, 2013, 12:38:10 am
content: Quote from: true on July 29, 2013, 12:32:33 amNot so much..QuoteMy sincerest apologies for offending you with a joke.

author: don.r
author_rank: Frequent Contributor
timestamp: July 29, 2013, 01:32:49 am
content: Quote from: true on July 29, 2013, 12:18:41 amGiven that the UT136D only does 230V for NCV, its most likely true here as well. Remains to be confirmed, however.

author: true
author_rank: Frequent Contributor
timestamp: July 29, 2013, 01:44:29 am
content: Quote from: don.r on July 29, 2013, 01:32:49 amYeah, that is what I originally wrote...I am concerned because for what I do it would be helpful. My PM55A works fine but takes a while to "boot"Quote from: true on July 28, 2013, 11:57:22 pm

author: don.r
author_rank: Frequent Contributor
timestamp: July 29, 2013, 02:19:56 am
content: Quote from: true on July 29, 2013, 01:44:29 amOoops... must have skipped past that bit. Sorry. It would have been good, even if they offered a D or E model with 120V NCV instead of 220V.

author: Wytnucls
author_rank: Super Contributor
timestamp: July 29, 2013, 05:31:21 am
content: NCV is good for the States too on this one; it triggers at any voltage above 100V RMS.

author: Electro Fan
author_rank: Super Contributor
timestamp: August 16, 2013, 12:29:41 am
content: Anyone actually see/use the 139C yet?

author: Wytnucls
author_rank: Super Contributor
timestamp: August 16, 2013, 12:39:42 am
content: I held a sample in the Uni-T office before the release, but didn't have time to test it properly. It felt reasonably well made, but the low count (6000 max) put me off a bit.Here is a picture of the meter I took at the time, while in China:

author: Fsck
author_rank: Super Contributor
timestamp: August 16, 2013, 12:55:41 am
content: if you had one in your hand, should've distracted the workers and taken it apart.

author: Wytnucls
author_rank: Super Contributor
timestamp: August 16, 2013, 01:04:05 am
content: I was more interested in their new oscilloscopes.

author: Legit-Design
author_rank: Frequent Contributor
timestamp: September 09, 2013, 10:33:27 pm
content: MCU inside my UNI-T UT139C, pic below. Found this picture on chinese site:http://translate.google.com/translate?hl=en&sl=zh-CN&tl=en&u=http%3A%2F%2Fzhidao.baidu.com%2Fquestion%2F563770993.htmlMine had same MCU inside. At least is suspect it is mcu.I can provide teardown photos if enough people are interested.Yes, it has few movs and few ptc, 600V fuses. 10A fuse is physically smaller than "600mA" fuse, no room for bigger fuses and holders like UT61C/E series has.NCV, non contact voltage is really sensitive, it has 4 ranges, one to four dashes and it beeps more with more dashes.I just had excuse to take it apart, K-type temperature function was acting up. When it was in room temp it was 28 C when it should be 25 and when I heated it with my hand it went DOWN, I heated the tip with my lighter and temp went down to -200C. Now I took the batteries out and it's working normally again, room is 25 and hand is around 30, boiling water is around 98 to 99 C what is just tested, heat from lighter is really hot is just burned the heatshrink from k-type a bit. Earlier today I discovered if I short the temp input with a probe it showed me current room temp, but that wasn't the case. I put my meter in the freezer and it couldn't read the K-type properly anymore. It was around -20 below what it should be.

author: Lightages
author_rank: Unknown
timestamp: September 09, 2013, 10:38:21 pm
content: I would like to see more images.

author: Legit-Design
author_rank: Frequent Contributor
timestamp: September 09, 2013, 11:27:49 pm
content: http://imgur.com/a/984K7Gallery with all the pictures.Please excuse these amateurish shots, took these with my smartphone with flash on, most of them are in focus.Backlight is quite weak compared to UNI-T UT-61D, but good enough to see in dark.Meter feels rugged when handled, I wouldn't be afraid to drop it.MOVs arehttp://www.thinking.com.tw/documents/en-TVR.pdfTVR07681

author: Monkeh
author_rank: Super Contributor
timestamp: September 09, 2013, 11:28:45 pm
content: Well now, that looks a lot like a BS1362.E: That's because it is, with a 600V/200A rating as well as 250V/10kA.

author: Legit-Design
author_rank: Frequent Contributor
timestamp: September 09, 2013, 11:46:55 pm
content: Oh and the most important thingsautoranging is slow, in resistance, like with UT-61D but Continuity beeper is super fast.Binding posts are solid type and feel really good, much better than with my UT-61D/E. I have all three meters so I can do comparison.Manual quotes screen updates 2-3 times per second, looks faster than UT-61D, but doesn't have that analog bar graph thing.Max min includes Max-Min, so it shows difference.EDIT: Few bits... that oscillator is soldered from its can to the board. Case is held by two self tappers, battery cover with the fuse inside is held by machine screw into metal insert.More: microamps range resistance 101 ohms, milliamps 2,1 ohms, amps less than 0,10 ohms, amps range is really tricky to measure. All measured with UT61E with probes relatived out.for UT61D those are microamps 50 ohms, milliamps ~0.8 ohms (I think dave also has covered ut61d in his 100$ MM shootout)One more thing to point out, probes are super dull compared to normal uni-t 61d/e probesPlease check the gallery for more pictures:http://imgur.com/a/984K7/allWhat else should I test with this meter? I don't have any accurate references, but I can do comparative measurements since I doubt all three of my Uni-t meter are out of cal.

author: retiredcaps
author_rank: Super Contributor
timestamp: September 10, 2013, 05:29:45 am
content: Quote from: Legit-Design on September 09, 2013, 11:46:55 pmDoes it overshoot? That is, if you connect the UT139C to a DC or ATX power supply, does it show the correct DCV reading immediately?For example, if the power supply is set to 12.0V DC and turned off and then on, does the multimeter show 18.1V (this is overshoot), then 12.3V, and then finally 12.0V? Or does the UT139C show 12.0V right off the bat?

author: Legit-Design
author_rank: Frequent Contributor
timestamp: September 10, 2013, 06:10:01 am
content: Quote from: retiredcaps on September 10, 2013, 05:29:45 amCouldn't get any of my three meters (UT61E UT61D and UT139C) to overshoot with 12 volts.However I could replicatehttps://youtu.be/3-_dUB8vy8U?t=25m27sDaves test from his shootout and get consistent overshoot with UT61D switching 3.3V rail. Sometimes 4.5V sometimes 4.7V, or even 5V, and I could get atleast 4.5V oveshoot consistently. UT136C didn't show any overshoot with this setup. Sometimes I could get UT61E to overshoot 18V or so, but that was more random than consistent. UT136C gets there more gradually it shows 2.3 to 2.9V for a split second before goes to 3.3V.

author: lpc32
author_rank: Frequent Contributor
timestamp: January 13, 2014, 11:29:38 pm
content: Any new info or opinions? I can't find a manual, nor any official info in the manufacturer site.

author: lpc32
author_rank: Frequent Contributor
timestamp: January 15, 2014, 06:15:18 pm
content: Well, found the manual in some German site:Mirror:http://www.mediafire.com/download/cy2ysi5iixia6g4/uni-t_ut139a_ut139b_ut139c.pdfOriginal URL:http://www.pinsonne-elektronik.de/media/daten/UT139A_B_C_eng_uni-t_pinsonne.pdf

author: Legit-Design
author_rank: Frequent Contributor
timestamp: January 20, 2014, 06:16:12 pm
content: Frankie has these on his ebay store:http://www.ebay.com/itm/Uni-T-UT139C-True-RMS-Digital-Multimeter-Temperature-NCV-Backlight-/171213085325?pt=LH_DefaultDomain_0&hash=item27dd185a8dForUS $49.99I recommend buying from him, fastest shipping on ebay I've seen (from Hong Kong).Also a member on this forumhttps://www.eevblog.com/forum/profile/?u=26834. He can also source other things which are not listed on ebay.And he ships fast, faster than any other ebay seller. He will remove those batteries from the package, but thats so that customs wont stop the parcel, I've had parcels sent back to seller because because some other parcel included batteries, so they stopped whole load of packages.Some special prices for forum members:https://www.eevblog.com/forum/buysellwanted/brand-new-uni-t-ut61e-for-sale/Quotehttps://www.eevblog.com/forum/buysellwanted/fs-digitek-dt-4000zc-tekpower-tp4000zc-with-discountQuote

author: retiredcaps
author_rank: Super Contributor
timestamp: January 24, 2014, 06:58:58 pm
content: Video review and teardown by electronupdate, an eevblog member here, just posted Jan 24, 2014.Franky gets a shoutout.

author: electronupdate
author_rank: Regular Contributor
timestamp: January 25, 2014, 02:27:15 am
content: Quote from: retiredcaps on January 24, 2014, 06:58:58 pmIt's an interesting meter. The calibration mostly appears to be set by inside a serial eeprom (no trim pots on the board). Good for stability, not so good for service. I could not find any details on the main controller IC.The meter has 600V rated fuses which match the CAT rating which is also a step in the right direction (the previous ut61e I tore down used 250V BS1362 appliance fuses).Another item of note is that UNI-T needs a product manager. Each meter they produce does not fit into a nice cadence of features.... one always needs to make a decision on odd axis such as temp sensor versus resolution.

author: Legit-Design
author_rank: Frequent Contributor
timestamp: January 25, 2014, 02:56:53 am
content: Quote from: Legit-Design on September 09, 2013, 11:46:55 pmQuote from: retiredcaps on January 24, 2014, 06:58:58 pmLooks like they updated the board slightly, mine has silkscreen place for that bodged crystal. () That new board doesn't have that and SMD crystal is in place.

author: lpc32
author_rank: Frequent Contributor
timestamp: January 26, 2014, 04:24:57 pm
content: Thanks, electronupdate.Re board changes, maybe there are different versions in different regions?There are a few more details I wonder about, but I'll find out soon enough.

author: lpc32
author_rank: Frequent Contributor
timestamp: March 12, 2014, 04:27:03 pm
content: Some impressions:Build quality feels decent.The backlight turns off after a few seconds by itself. Quite annoying.The probes' tips aren't sharp. Similar to a ballpoint pen.

author: JonathanLee
author_rank: Newbie
timestamp: March 28, 2014, 04:52:26 am
content: DTM0660L IS HYCON HY12P65 Digital Multi-function Meter (DMM) ICshttp://www.hycontek.com/e-page2-HY12P.html

author: retiredcaps
author_rank: Super Contributor
timestamp: March 28, 2014, 07:02:11 am
content: Quote from: JonathanLee on March 28, 2014, 04:52:26 amThanks for sharing that information. I would have never figured that out.

author: awardcat
author_rank: Newbie
timestamp: July 19, 2014, 03:36:09 pm
content: Quote from: JonathanLee on March 28, 2014, 04:52:26 ambut...this page says HY12P65 have 5000 counts , but ut139C have 6000 countsupdate : in the datasheet is 6000 counts

author: IGNT
author_rank: Newbie
timestamp: July 25, 2014, 04:44:41 am
content: Woow that seems, good stuf ... how can i buy it, in indonesia. would you share me a presaller in indonesia who sale this good stuf...regardsIGNITERNote : Sorry About my English language , because i javanese...

author: PedroDaGr8
author_rank: Super Contributor
timestamp: July 25, 2014, 05:15:09 am
content: Quote from: IGNT on July 25, 2014, 04:44:41 amFranky (iloveelectronics) on this forum sells this meter.http://www.ebay.com/itm/171213085325He ships pretty much worldwide from HK. You might be able to get it a tad cheaper via this forum as he doesn't have to pay ebay fees.

author: IGNT
author_rank: Newbie
timestamp: August 08, 2014, 07:54:56 am
content: thank's for nice reply, PedroDaGr8, my apologize ,for late response.RegardzIGNITER

author: boo9
author_rank: Contributor
timestamp: September 01, 2014, 01:24:09 pm
content: Anybody has a link to a _searchable_ PDF for UT139C ?

author: lpc32
author_rank: Frequent Contributor
timestamp: September 01, 2014, 05:15:21 pm
content: Not searchable, but the PDF on UniT's site is better quality than the previously available one:http://www.uni-trend.com.cn/uploads/soft/wanyongbiao/UT139A.UT139B.UT139C%20-Manual-en.pdf

author: mariush
author_rank: Super Contributor
timestamp: September 02, 2014, 01:35:33 am
content: Here, I OCR'ed it ... careful though, it's not proofread, no spell checking, just automated ocr .

author: Ether
author_rank: Contributor
timestamp: October 11, 2014, 06:08:21 am
content: This meter looks pretty good. Just wondering, in comparison with the UT61E, does it outshine it in terms of usefulness? I understand that both have their pros and cons but does the resolution on the 61E outweigh the 139C's better input protection, NCV, backlight, auto power-off etc. ?By the way, I'm asking because I'm looking to get another meter to complement my Fluke 73 III that has been really reliable but somewhat lacking in features so I appreciate any help.

author: Creep
author_rank: Regular Contributor
timestamp: October 11, 2014, 06:51:36 am
content: Totally depends on what you want to use it for. If your thinking of probing mains a lot etc. then you probably want to go for the 139C. If your only working on the bench, then UT61E is your best bet I would say.

author: Ether
author_rank: Contributor
timestamp: October 11, 2014, 06:55:54 am
content: Yeah, I think what you said made sense.I think I'll probably get a UT61E for the bench and use my Fluke for any high-voltage work.After all, the 22000 count is really appealing to a guy with more than a few 6000 count meters.

author: Wytnucls
author_rank: Super Contributor
timestamp: October 11, 2014, 07:10:04 am
content: Don't rely on the last digit of the 61E.The meter doesn't have an external voltage reference and in my experience drifts way too much for a 4 1/2 count meter.

author: Ether
author_rank: Contributor
timestamp: October 11, 2014, 07:24:34 am
content: Then Wytnucls, in light of that, would you recommend the 139C over the 61E, seeing that the last digit is useless anyway?

author: Wytnucls
author_rank: Super Contributor
timestamp: October 11, 2014, 07:37:40 am
content: I guess so, as I would happily trade my 61E for a 139C. But compare features and get the one that fits your needs better.

author: Legit-Design
author_rank: Frequent Contributor
timestamp: October 11, 2014, 03:10:49 pm
content: Quote from: Ether on October 11, 2014, 06:08:21 amI wrote elsewhere on the NCV function:Quote from: Legit-Design on October 11, 2014, 02:46:55 pmstill just my opinion and experiences, your mileage may wary. the youtube review/teardown by a forum member only showed NCV when close to mains wire, and mine works just the same way with mains voltages, but it's the other things I'm worried about.

author: lpc32
author_rank: Frequent Contributor
timestamp: October 11, 2014, 03:33:07 pm
content: Quote from: Ether on October 11, 2014, 06:08:21 amThe light turns off automatically after 15 seconds, and to turn it on you need to hold the button for 2 seconds, so I find it rather useless. Unless there's a hidden way to configure it to stay.

author: Ether
author_rank: Contributor
timestamp: October 12, 2014, 02:11:37 am
content: I hope I'm not hijacking this thread by asking this, but does anybody reckon that the dt-2843r ot the dt-4000zc might be of better value in comparison to the 139C?

author: n33d
author_rank: Newbie
timestamp: October 19, 2014, 05:01:23 am
content: Hi All,I am new to DMM stuff and UT139C is my first DMM. Just got it yesterday.while playing with the meter, i've noticed that it behaved strangely when i test for resistance. i used my test lead and clamp them together, it showed 0.00 Ohm(expected 0.1 or 0.2ohm) but when i switched to continuity test, it showed 0.02. Test done on other wires and the pattern is consistent. Always +0.02 Ohm when switched to continuityIs this "auto-zero" feature from uni-t???

author: Wytnucls
author_rank: Super Contributor
timestamp: October 19, 2014, 05:35:27 am
content: Resolution is 0.1 Ohm on the lowest 600.0 Ohm range with an accuracy of 1%+2, so assuming your test leads have a true resistance of 0.2 Ohm, any reading between 0.3 and -0.1 Ohm would be within specs.

author: lpc32
author_rank: Frequent Contributor
timestamp: October 19, 2014, 04:55:58 pm
content: Quote from: Ether on October 12, 2014, 02:11:37 amI guess that depends on your requirements. Look for features you must have and see which meters match.

author: Lightages
author_rank: Unknown
timestamp: October 19, 2014, 05:57:28 pm
content: The main differences to consider IMHO:DT2843R has True-RMS with DC, UT139C appears to be True-RMS AC onlyDT2843R has a slow continuity test, UT139C is fastDT2843R has limited input protection, UT139C has much better input protectionDT2843R does not have a non-contact voltage detector, UT139C has NCVDT2843R has a better made temperature probe, UT139C is a simple welded bead end.DT2843R 4000 count, UT139C 6000 countDT4000ZC is close to the same as the DT2843R, but has PC connection and software.Conclusion:Need a safer meter, UT139C. Need fast continuity, UT139C or DT-4000ZC. Need NCV, UT139C.Need True-RMS +DC, DT2843R.Need PC logging, DT-4000ZC.I would recommend the UT139C to most people from what I have seen. I have a DT2843R and it is a very good meter for the money too, but I think the UT139C edges it out for most uses.

author: lpc32
author_rank: Frequent Contributor
timestamp: October 19, 2014, 10:02:24 pm
content: Don't forget that value also includes price.And there may be some differences in accuracy.

author: jarvis
author_rank: Contributor
timestamp: October 20, 2014, 02:33:50 am
content: Low AC bandwidth (1.5kHz) TRMS of UT139C seems not accurated for square wave or higher crest factor waveform even it is lower frequency.

author: Wytnucls
author_rank: Super Contributor
timestamp: October 20, 2014, 03:44:31 am
content: AC bandwidth is 1kHz. Crest factor up to 3.0 for low voltage signal which has to reach at least 5% of the range for accuracy.That should cover square, triangle and half rectified sine waves.

author: Ether
author_rank: Contributor
timestamp: October 21, 2014, 11:04:18 am
content: Thanks to everyone for the replies. I finally settled on a UT139C over the Digitek offerings after comparing the specs again. Personally, I think that the poor-quality temperature probe/thermocouple included can probably be replaced, albeit at an additional cost. The deal-breaker for me was the continuity. Slow continuity is a pain to work with and I would happily trade the True-RMS DC for fast continuity. The NCV and 6000 counts just sweetened the deal. I'll post my impressions after receiving it but from what it looks like, it looks pretty promising. By the way, anybody knows what the V.F.C means. I'm guessing variable frequency something, correct me if I'm wrong.

author: HiTech
author_rank: Regular Contributor
timestamp: October 21, 2014, 01:31:15 pm
content: Quote from: Lightages on July 28, 2013, 09:49:20 pmDon't worry about it .... after all, the old saying "you get what you pay for" is very often true. At the end of the day, it's still a $50 DMM from a company that probably trained field mice to assemble it to maintain a profit margin.

author: lpc32
author_rank: Frequent Contributor
timestamp: October 21, 2014, 09:40:49 pm
content: Another point: the UT139C's temperature resolution is only 1C.VFC, the manual says, is for variable frequency voltage. Maybe someone else can shed more light.

author: Lightages
author_rank: Unknown
timestamp: October 21, 2014, 09:44:18 pm
content: The VFC function is supposedly a high roll off filter to reduce noise on the measurement from switched variable frequency motor drives.

author: Legit-Design
author_rank: Frequent Contributor
timestamp: October 24, 2014, 11:27:26 am
content: Quote from: lpc32 on October 21, 2014, 09:40:49 pmAlso the temperature is all over the place when multimeter comes from the freezer, yes I tested mine, left it in the freezer and took it in the room temperature. It took a long time to warm up and start to show up reasonable temperatures. Maybe this is because there is no cold junction compensation? Or the temperature measurement is just crap. Might be a problem in some places where it is actually so cold it snows in the winter, and some people might want to use it to troubleshoot their car or something. But if used in normal room temperatures it might be of some use.Having 2x AA batteries (UT139C) in a multimeter is a huge plus over single 9V battery (UT61E/D). Now that I've got to use mine and seems like the 9V batteries are flat way too soon. More time without battery warning icon means more measurements that are most likely accurate.

author: Ether
author_rank: Contributor
timestamp: November 03, 2014, 08:55:05 am
content: I just received my UT139C. Haven't done any extensive testing yet but I must say, the construction quality is excellent. I especially liked the sturdy holster which would easily protect the meter from a fall off the bench. Backlight is acceptable as well and the selector wheel is nice to turn and relatively "clicky" but some might consider it too mushy. Included probes are acceptable but I recommend Fluke TL75 leads.I tried to replicate Legit-Design's NCV problem. Unfortunately, I couldn't get it to go off at my earphones (plugged into a computer). However, I noticed that it works better with the holster off but I still wouldn't trust my life on this. Useful in a pinch but if you're doing high voltage work frequently, invest in a proper voltage pen.The temperature probe is pretty cheap and only goes up to 230 celsius if I'm not wrong but this meter is only good for ballpark measurements due to its low resolution.For a first impression, that's more all or less all the annoying flaws I spotted. Don't get me wrong though, this is an excellent meter for the price point and the features/cost ratio is superior to practically every other meter at this price point. Also, the input protection is properly designed with the standard MOVs and PTCs (600V) so this would be a better option for beginners as it is less likely to spontaneously combust if you screw up. Fuses are properly rated at 600V and are HRC fuses.That's about it but I would be happy to try any other tests that others might suggest.

author: Monkeh
author_rank: Super Contributor
timestamp: November 03, 2014, 09:21:02 am
content: Quote from: Ether on November 03, 2014, 08:55:05 amIf you'd trust your life to a voltstick, you're an idiot. They are for locating wires, not determining if they're dead or not.

author: Ether
author_rank: Contributor
timestamp: November 03, 2014, 09:46:06 am
content: Perhaps I didn't phrase that correctly, but essentially, knowing where the wires are is pretty important if you don't intend to live a shorter than average life. Determining whether the wires are dead or not is a different matter so you do have a point there Monkeh.

author: gigahertz
author_rank: Newbie
timestamp: November 03, 2014, 03:45:01 pm
content: Gents,On your web site is mentioned “Optional AC/DC 60A current clamps in different models to measure current up to 60A(1mv=1A)”;Where can I found the current clamp? Has it a separate ordering code?Regards!

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: November 03, 2014, 04:01:46 pm
content: Quote from: gigahertz on November 03, 2014, 03:45:01 pmUni-T actually don't have anything like that yet in their product line. You should be able to use any generic current clamps that work with multimeter though, such as this:http://www.amazon.com/Tecpel-CA-60-AC-Current-Clamp/dp/B002IRU3IM

author: SSchaffrath
author_rank: Newbie
timestamp: December 11, 2014, 01:08:57 pm
content: Hi guys,i blowed the small fuse up when i was testing itWhich replacement can i use, i cant find a 600ma 600v ceramic fuse...

author: Lightages
author_rank: Unknown
timestamp: December 11, 2014, 10:16:47 pm
content: I am beginning to think that Dave needs to enforce mandatory country settings in member's profiles. How many times do we need to ask people to tell us where they are so they can buy from the right place?Franky has a 630mA 500V fuse but that does no meet the CAT rating. But I am sure if you ask Franky he can get the right fuse.

author: SSchaffrath
author_rank: Newbie
timestamp: December 12, 2014, 04:24:09 am
content: Im from Germany.I tried it once to buy something from his ebay shop and it doesnt worked with German ebay.

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: December 12, 2014, 04:50:51 am
content: Quote from: SSchaffrath on December 12, 2014, 04:24:09 amIs it still the case right now? As far as I know people from Germany should be able to see my store nowhttp://stores.ebay.com/99centhobbiesI'm out of stock on the 630mA 500V fuses though. 600mA 600V is actually a tricky one to source...

author: SSchaffrath
author_rank: Newbie
timestamp: December 12, 2014, 04:55:09 am
content: Cool now i can see itLast time i checked it, it was not possible.Which alternatives do i can use for the UT139C ?

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: December 12, 2014, 05:20:31 am
content: Quote from: SSchaffrath on December 12, 2014, 04:55:09 amI will try to source some 6x32mm 600mA 1000V fuse, which would be suitable for both the UT139C and Brymen BM257S that I sell. It will likely take some time though as these fuses are not common.In the mean time I guess you can try to buy some 500mA 500V or above rated fuse, which should do the job just fine as long as you know the limitations.

author: SSchaffrath
author_rank: Newbie
timestamp: December 12, 2014, 05:22:34 am
content: Ok then i buy for the mean time your suggested ratings and when you sourced the suitable fuses for these meter then i buy some from youDo i can use 6.3mmx32mm aswell?

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: December 12, 2014, 05:26:42 am
content: Quote from: SSchaffrath on December 12, 2014, 05:22:34 amYes, that should be fine. The sizes always vary slightly but the fuse holder should be able to accommodate them.

author: Yago
author_rank: Frequent Contributor
timestamp: December 12, 2014, 11:56:24 am
content: The 857S is out now 3Room.They fixed the backlight (perhaps some other changes IDK)!

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: December 12, 2014, 01:13:49 pm
content: Quote from: 3roomlab on December 12, 2014, 10:10:25 amI couldn't get good pricing on that model so I gave up a long time ago. The tme.eu pricing was (still is) incredibly low there's no way I would be able to compete.

author: SSchaffrath
author_rank: Newbie
timestamp: December 12, 2014, 02:29:48 pm
content: Here Franky,http://www.alibaba.com/product-detail/6x32-DMM-fuse-1000Vdc-600mA_60049386394.html1000fuses minimum

author: lpc32
author_rank: Frequent Contributor
timestamp: December 12, 2014, 03:06:01 pm
content: Aren't there more specific specs needed than just the current and voltage ratings?SSchaffrath: Try ebay.com instead of ebay.de. Maybe not all international sellers are listed in the .de site.

author: Lightages
author_rank: Unknown
timestamp: December 12, 2014, 05:56:35 pm
content: If you look at the image of the fuses, you can see that they are also rated for breaking 10kA and have a UL symbol on them. Whether they actually are UL tested is another matter. The fact that they show a clean room and some kind of IC inspection or testing lab leads me to believe that they are not showing the actual environment they have for making fuses

author: classical
author_rank: Regular Contributor
timestamp: January 06, 2015, 07:51:03 am
content: Quote from: Lightages on October 19, 2014, 05:57:28 pmCould this be confirmed in the meantime? In the manual of the 139C I find all the three symbols listed (Table VIII "Knobs and Keys for Range selection").

author: Wytnucls
author_rank: Super Contributor
timestamp: January 06, 2015, 09:08:19 am
content: 139C measures true RMS AC only. Bandwidth is narrow at 1kHz for voltage and current.

author: classical
author_rank: Regular Contributor
timestamp: January 06, 2015, 09:19:17 am
content: Thanks for the reply.

author: lpc32
author_rank: Frequent Contributor
timestamp: January 06, 2015, 03:59:57 pm
content: Makes me wonder. With a 1kHz bandwidth, what would you expect to see at 5/10/20kHz?

author: Wytnucls
author_rank: Super Contributor
timestamp: January 06, 2015, 04:11:08 pm
content: Something like this, but with the slope starting at 1kHz:

author: lpc32
author_rank: Frequent Contributor
timestamp: January 06, 2015, 04:16:44 pm
content: So as long as it's pure sine you can just compensate?

author: Wytnucls
author_rank: Super Contributor
timestamp: January 06, 2015, 04:29:51 pm
content: Probably not, as the curve could change shape with input voltage.

author: lpc32
author_rank: Frequent Contributor
timestamp: January 06, 2015, 08:25:46 pm
content: I see.

author: andrija
author_rank: Regular Contributor
timestamp: January 06, 2015, 09:17:59 pm
content: These fuses go for 40-50 dollars EACH, as per Digikey. Even in 1000's quantities they cost $25. How can these $70 multimeters afford to have them (and you need TWO)?Actually, it's just Digikey. Element 14 only charges around 8 dollars and a 5 pack on Ebay (in original packaging) is around 45 so it's not THAT bad. Not sure why Digikey charges so much, must be a pricing mistake.

author: eas
author_rank: Frequent Contributor
timestamp: January 07, 2015, 04:41:56 am
content: Has anyone explored the (unsoldered) header on the PCB (visible)?VDD, WP, SLC, SDA, V1, and two labeled CAL?

author: mmatic
author_rank: Contributor
timestamp: January 07, 2015, 06:06:56 pm
content: Hey!1.) Can anyone who owns this UT139C meter please measure burden voltage?2.) What is measured accurancy at uA, mA, A range?3.) Is contuinity test fast?Best Regards Matic

author: lpc32
author_rank: Frequent Contributor
timestamp: January 07, 2015, 06:49:18 pm
content: 1. Burden voltage:https://www.eevblog.com/forum/testgear/new-trms-uni-t-ut139c-dmm-is-available-now/msg289230/#msg2892302. Accuracy beyond what's indicated in the manual?3. Continuity is pretty fast.

author: mmatic
author_rank: Contributor
timestamp: January 07, 2015, 07:05:54 pm
content: Quote from: lpc32 on January 07, 2015, 06:49:18 pmHi!Do you maybe own ut139? Does this multimeter has better current accurancy that ut61e?Best Regards Matic

author: Lightages
author_rank: Unknown
timestamp: January 07, 2015, 10:08:38 pm
content: I have had both and the UT61E is rated more accurate of course but my UT139C is as accurate from my recollection. It doesn't mean it will stay that way but it is as accurate as most people need.

author: ataradov
author_rank: Super Contributor
timestamp: February 01, 2015, 03:00:30 am
content: Does anyone know how the frequency measurement works? Is it only for AC voltage with positive and negative swings?I'm trying to measure frequency on the MCU pin, which is 1 kHz, 0-3.3V, 50% duty cycle. And the meter shows 0.At the same time if I touch any of the probes, I get 60 Hz (I'm in the US), so it can measure something.

author: Lightages
author_rank: Unknown
timestamp: February 01, 2015, 04:55:29 am
content: I can read 90mV P-P no problem at 1kHz on the Hz measurement selection on the dial. On the Hz subselection in ACmV I get a reading at around 50mV P-P.

author: ataradov
author_rank: Super Contributor
timestamp: February 01, 2015, 05:17:11 am
content: So it looks like it needs "hard 0v". With pullups on MCU pins, the logical "0" voltage is actually around 40 mV and this is not enough for frequency measurement.I've put a battery between the ground lead and the circuit ground to offset the measured voltage and got proper frequency reading on the "Hz" setting. At the same time frequency measurement on AC voltage setting still shows 0.

author: Lightages
author_rank: Unknown
timestamp: February 01, 2015, 05:57:21 am
content: Sorry Alex, I didn't answer your question. I was busy doing something else and casually did a test that wasn't very helpful. I just did a test that was actually related to your question!Yes, it seems that the frequency measurement needs a zero crossing. I was unable to read 0-3.3V with the meter. I was able to read the frequency by putting a 2uF cap in series with the probe. Try a cap of some value and I think you will get your measurement.

author: ataradov
author_rank: Super Contributor
timestamp: February 01, 2015, 06:06:20 am
content: Yes, using a capacitor is an option, but it becomes a hassle. I considered using a meter for quick frequency check to save time on powering up the scope. With the need to look for capacitor, it does not save much time.

author: electr_peter
author_rank: Unknown
timestamp: February 05, 2015, 09:21:45 am
content: From video reviews it seems that UT139C beeps whenever rotary dial is turned. Who thought it was a good idea?Is there a way to turn off this annoying beep?Buttons also beep, right? Is there a way to turn off button beep?HW mod would help (to disable beep by default) if only there is way to get info about selected continuity mode (to enable beep).

author: ataradov
author_rank: Super Contributor
timestamp: February 05, 2015, 05:24:45 pm
content: Yes, it does beep and it is indeed quite annoying. I have no Idea why manufacturers put all those blinky and beepy things all the time, it feels like they don't think their product is good enough without them.I'd like too see a mod myself.

author: electr_peter
author_rank: Unknown
timestamp: February 05, 2015, 06:21:35 pm
content: Why do designers think that beeping on any input/activity is a good idea? Do they want do drive us crazy? Turn on -> beep, rotate dial -> beep, press button -> beep, ... At least give an option to disable it.I would force such designer to use computer keyboard and mouse where any button press leads to old style type writer loud key press sound. That will show them.Does UT139C turn on/blink back-light on continuity as well as beep? If so, permanently disabling beep would do (almost) no harm for functionality. I have done so with some multimeters which have blink option.

author: ataradov
author_rank: Super Contributor
timestamp: February 05, 2015, 06:25:41 pm
content: It definitely does not turn on the back-light, I'm not sure what happens if the back-light is already on, I don't have the meter at hand, but I'm pretty sure it won't do anything special.

author: Lightages
author_rank: Unknown
timestamp: February 05, 2015, 08:30:10 pm
content: In the case of the back light indicating continuity, no. But if you want to mod the beeper then maybe connecting the back light to the beeper output in some way would be a good substitute. I think needing to look for the back light for continuity indications would be counterproductive. though.

author: Didix
author_rank: Regular Contributor
timestamp: February 08, 2015, 08:39:57 am
content: Quote from: iloveelectronics on November 03, 2014, 04:01:46 pmWhy should I buy a separate $80 clamp when I can get complete clamp meter for $30?http://www.amazon.com/dp/B005HOPRRK/ref=wl_it_dp_o_pC_nS_ttl?_encoding=UTF8&colid=1QZMU23HSUUOC&coliid=I3GLO3CT1DUA92These words are not meant as a provocation!!I really would like to know, why one should buy the UT139C plus the referenced clamp instead of a UT61E plus the UT203?-Didix

author: Lightages
author_rank: Unknown
timestamp: February 08, 2015, 04:01:05 pm
content: If you are going to be using a clamp meter it implies that you will be working on high energy circuits. The UT61E is not suited for high energy circuits at all. It does not have proper input protection. The UT139C has much better protection and appears to actually be built correctly for high energy circuits.Until Uni-T brings out their current clamp for the meter, if they ever do, I would suggest getting a separate clamp meter. The UT211B is pretty good for the money but it is not known if it meets its CAT ratings neither. Good clamp meters tend to cost $200.

author: omgfire
author_rank: Regular Contributor
timestamp: February 08, 2015, 04:25:32 pm
content: Quote from: Lightages on February 08, 2015, 04:01:05 pmCan you explain 3x price difference between UT211B and UT210E?

author: electr_peter
author_rank: Unknown
timestamp: February 08, 2015, 04:27:44 pm
content: Quote from: Didix on February 08, 2015, 08:39:57 amIt depends on what you do and what do you want to achieve. Do you need DMM only for electronics (low power stuff)? Then clamp is useless in any form. Do you need to measure high AC/DC currents? Then you need a clamp.Clamp with built-in DMM or DMM plus separate clamp adapter - again, it depends. Clamp with built-in DMM has an inconvenient form factor (too massive, too long, too narrow, no stand), but is only one piece instrument.Price and characteristics wise you have to choose yourself - all depends on requirements.

author: edavid
author_rank: Super Contributor
timestamp: February 08, 2015, 04:29:31 pm
content: Quote from: Lightages on February 08, 2015, 04:01:05 pmWhy do you say that? I only use mine on household circuits.

author: Didix
author_rank: Regular Contributor
timestamp: February 15, 2015, 07:04:45 am
content: Now I got a UT39C, too.I thought, the NCV could extend the features of my DMM collection.However, the reach of the NCV isverymoderate. The line needs to be closer than a half inch.I was not able to detect any line inside my walls (230V).Somehow disappointing experience ...-Didix

author: ataradov
author_rank: Super Contributor
timestamp: February 15, 2015, 07:12:03 am
content: I think its primary function is to find out if those uninsulated wires sticking out of the wall will kill you if you want to do something with them, and not finding wires behind the wall.

author: SeanB
author_rank: Super Contributor
timestamp: February 15, 2015, 07:22:48 am
content: Best use of a NCV test is to see if a cable is broken internally, and near which end the break is. You have to be right next to the cable and run down the length, and then it works well.To detect cabling in walls you are much better off using a stud finder that has a cable detector built in as well, it is a more specialised part more appropriate for this use. I have one, even though most walls here in SA are brick, it does work to tell where the buried conduits are before drilling into a wall to avoid a very nasty surprise.

author: Didix
author_rank: Regular Contributor
timestamp: February 15, 2015, 07:52:10 am
content: Ok, good points!-Didix

author: Maxlor
author_rank: Frequent Contributor
timestamp: February 15, 2015, 12:13:59 pm
content: Quote from: omgfire on February 08, 2015, 04:25:32 pmThe UT211B is TrueRMs, the UT210E isn't. The UT211B also has a 600mA AC (but not DC) range, which might make it useful as a leakage tester.From my point of view, as a hobbyist mainly playing with low power DC circuits, the UT210E is far better value for money.

author: Lightages
author_rank: Unknown
timestamp: February 15, 2015, 03:09:09 pm
content: Quote from: edavid on February 08, 2015, 04:29:31 pmActually household circuits, if you are referring to house wiring, are considered high energy. If I remember correctly, the distribution panel and any circuits within 10 meters of the panel.

author: Lightages
author_rank: Unknown
timestamp: February 15, 2015, 03:13:06 pm
content: Quote from: Maxlor on February 15, 2015, 12:13:59 pmThe UT210E is TRMS. The main differences I see are the current ranges, and the UT210E is 2000 count and the UT211B is 6000 count with slightly better accuracy specifications.

author: edavid
author_rank: Super Contributor
timestamp: February 15, 2015, 08:06:48 pm
content: Quote from: Lightages on February 15, 2015, 03:09:09 pmDo you have a citation for that? I don't think it's true here in the US.

author: naughtilus
author_rank: Contributor
timestamp: February 28, 2015, 07:58:14 pm
content: For the Uni-T UT139C we need theSIBA 7012540.0.630(page 620), which is 700VAC, 630mA, 50kA, ceramic w/filler and 6.3mm x 32mm.Found these sources doing a google search:DIYtrade.comand11467.com(no affiliation). Indicatively prices are under $8 for 100 unit lot on these, which is not bad for a difficult to find fuse I reckon. Any group buys organized before on this forum or maybe Franky is interested offering this type of fuse for his ebay store (where I got my 139C originally)? Franky, do you do pre-orders where we give you money and when there is at least 100 of us you buy a lot and send us the fuses? Small amount per person at stake and we are all bound eventually to blow the voltage fuse considering this is somewhat of an electricians DMM, not for bench work really. I bought it to poke the mains at home.Thoughts?

author: Lightages
author_rank: Unknown
timestamp: February 28, 2015, 08:16:36 pm
content: Quote from: edavid on February 15, 2015, 08:06:48 pmActually, a US company says so! The most concise explanation comes from Fluke. It isn't a very rigorous explanation but it does confirm my assertion.http://www.fluke.com/fluke/m2en/training/safety/Look for ABCs of multimeter safety.This is why I almost always suggest a properly rated meter for even casual bench users. The temptation to use it on home wiring is too much.

author: edavid
author_rank: Super Contributor
timestamp: February 28, 2015, 08:46:39 pm
content: Quote from: Lightages on February 28, 2015, 08:16:36 pmThat document does not define "high energy".Anyway, it says that CAT III is three-phase distribution, so doesn't that mean that single-phase house wiring would be CAT II?

author: naughtilus
author_rank: Contributor
timestamp: February 28, 2015, 09:14:56 pm
content: I have three-phase outlets (400V) in my house. Those would be CAT III most likely.

author: Lightages
author_rank: Unknown
timestamp: February 28, 2015, 09:37:29 pm
content: Do I need to read everything and repeat for everyone?''Within a category, a higher working voltage”(steadystate voltage) is associated with ahigher transient, as would be expected. Forexample, a CAT III 600 V meter is testedwith 6000 V transients while a CAT III 1000 Vmeter is tested with 8000 V transients.""CAT III Three-phase distribution, including • Equipment in fixed installations, such as switchgear and polyphase motors.single-phase commercial lighting • Bus and feeder in industrial plants.• Feeders and short branch circuits, distribution panel devices.• Lighting systems in larger buildings.• Appliance outlets with short connections to service entrance."

author: naughtilus
author_rank: Contributor
timestamp: February 28, 2015, 09:45:04 pm
content: Transients... pffft. Just roll the dice man! O0

author: Wytnucls
author_rank: Super Contributor
timestamp: February 28, 2015, 10:26:56 pm
content: A three-phase outlet is considered CAT III, as is a single-phase outlet within 10 meters of the distribution panel.

author: Lightages
author_rank: Unknown
timestamp: February 28, 2015, 11:26:31 pm
content: Obviously "High Energy" is a relative term. I think that anyone with experience with electricity would agree that Class III would be classed as "High Energy". This, especially, when compared to bench electronics energy levels.

author: naughtilus
author_rank: Contributor
timestamp: February 28, 2015, 11:36:20 pm
content: Basically everything in my house is CAT III since everything is within 10m radius from the distribution boards.The Uni-T UT139C + Fluke TL71 leads seems good enough for measuring single phase <240Vac at home and <24Vdc/1A for hobby projects. Not sure if I wanna poke in the 3-phase outlet though... I'd call it CAT II and CAT III-ish.

author: Lightages
author_rank: Unknown
timestamp: February 28, 2015, 11:42:43 pm
content: Quote from: naughtilus on February 28, 2015, 11:36:20 pmYes! You understand now. I am glad someone will know their risks and won't be blindly poking probes where they could be a hazard. Now you know the risks and can asses them to your liking instead of just thinking you are safe.

author: naughtilus
author_rank: Contributor
timestamp: March 01, 2015, 12:33:20 am
content: Also it seems leaving the protective caps on the leads increases their CAT rating. This is most likely because by reducing the exposed metal tips area, chances of arc flash occurring during a large transient when you pull out the tips are greatly reduced. HV cutouts between the inputs and fuses also seems to help prevent this. Plasma ballin your face can't be fun.That Fluke ABC pdf is a fun read. Thanks for sharing LA.

author: Wytnucls
author_rank: Super Contributor
timestamp: March 01, 2015, 01:29:19 am
content: Quote from: naughtilus on February 28, 2015, 11:36:20 pmFor three-phase outlets in Europe, the voltage to consider for IEC CAT III environment is between neutral and any phase (230V 50Hz), not the voltage between two phases (400V 50Hz).There is a big jump in transient energy test between CAT II and CAT III/CAT IV, as the voltage source impedance is reduced from 12 Ohms to 2 Ohms.If the UT139C lives up to its CAT rating, it's all good up to 600V in a CAT III environment. Of course, without independent testing, that CAT rating is not to be trusted.

author: naughtilus
author_rank: Contributor
timestamp: March 01, 2015, 01:37:21 am
content: Quote from: Wytnucls on March 01, 2015, 01:29:19 amSo 400V between phases for a domestic plug within 10m distance of the dist. board is what category?BTW. How'sfor safety? OrThe future Photonicinduction?

author: Wytnucls
author_rank: Super Contributor
timestamp: March 01, 2015, 01:51:35 am
content: Three phase outlet, regardless of distance is CAT III, requiring a meter rated CAT III 600V minimum, being lowest voltage for CAT III.

author: naughtilus
author_rank: Contributor
timestamp: March 01, 2015, 02:17:31 am
content: Thanks.

author: mos6502
author_rank: Frequent Contributor
timestamp: September 11, 2015, 11:38:43 pm
content: Looks like the boards went through a few revisions. I've attached pics of the PCB of the meter I got some three weeks ago. The first in this thread was marked 190612-1, mine is 190612-4, so presumably it's the fourth revision. As you can see, they added another MOV. The board also looks better made than the the old one, all the components are straight and the soldering looks excellent.

author: mematyi
author_rank: Contributor
timestamp: October 03, 2015, 02:30:46 pm
content: Hello there!I just got this meter, and well it is quite good for the price. Mine is also the 4.th revision.I wonder if anyone read the chip's datasheet? It says that there are serial output.There are also connections on the PCB for communicating(sda,scl) and for calibrationApparently the "cal" traces do not lead to the mcu, but the RMS chip if i am correct

author: Ichabod
author_rank: Newbie
timestamp: December 24, 2015, 12:20:45 pm
content: Quote from: JonathanLee on March 28, 2014, 04:52:26 amBut i ask me where UNI-T takes the other 1000 Counts- on HYCON stands 5000 only!

author: Electro Fan
author_rank: Super Contributor
timestamp: December 24, 2015, 07:54:09 pm
content: Quote from: edavid on July 28, 2013, 08:50:31 pmOn a related question, why wouldn't the manufacturer read the half a zillion posts about the UT61E and their other models and either modify or add one or a few models that better address the user feedback?Seems like they have the ability to make many different models - why not put the most popularly requested features into one or two really, really well-received combinations?No doubt, the UT61E has done pretty well - but it could be even more successful.As it is you can choose model A with this and this but not that and that, or you can get model B with that and that but not this and this. I could understand it if they only made one or two models but when they have a bunch of models why not add a backlight here and a whatever there?The manufacturer would probably say "we've studied the market and segmented the market by user types and use-cases and we've determined that the profile of a person who buys a UT61E is someone who has $45 not $48 and they don't value having a backlight". On the other hand, we have found the profile of a UTXYZ customer and they have even less money but they like to see their digits in the dark."The answer is that in most companies the Marketing department that does "outbound" marketing communications rather than the "inbound" determination of market requirements and opportunities. Meanwhile Engineering is generally too busy and often doesn't have the skill set, experience, budget, or charter (at least one of the above is missing) to sort through the signals and noise in the market, and the Sales people get listened to even less than the customers. As a result you get a hodgepodge of "almost" products in a product family all scattered around the targets rather than hitting any of the targets squarely. Of course since the targets change over time (due to changes in technology and competition as well as use cases) it's an evolutionary process but the low hanging fruit is to thoughtfully incorporate user feedback regarding current products. It sure does seem like the DMM market could benefit from better product planning rationalization.Having said all that, it's probably easier to be a critical customer than a successful product marketing manager.

author: Lightages
author_rank: Unknown
timestamp: December 24, 2015, 08:44:52 pm
content: I have come to the conclusion that multimeter manufacturers really don't spend much time worrying about customer feedback. They seem to design in the dark and think they are designing to lead the consumer. The exception seems to be Uni-T. They seems to just make a whole pile of different models with as many variations as possible and hope tat something sells. If they were actually trying design for what people want, then they could cut down their range of models to 1/10 of what they have now.

author: adrianf88
author_rank: Contributor
timestamp: January 24, 2016, 07:36:10 pm
content: Hey there everyone, a few months ago i was looking at the 139c as my next buy but i just couldn't source it locally. I know Franky is an ebay seller that everyone recommends around here, and i was going to buy it from him. But after i bought several items from ebay and recieved them all banged up by the local mail and customs office and by no fault of the seller i decided to wait for it to be available locallyA few days ago i finally found it in a store in my city and next thing tomorrow after i leave work i plan on buying it.But seeing that its price is a 1/5 of my monthly salary i do feel like i should bury my impulses and think about it for a minute or two.My questions are:How reliable is it for bench operation only?How much drift should i expect after 1 year? What about 5?Can i calibrate it once it drifts?When something eventually goes poof! and releases the magic ghost, how likely am i to find the necessary parts and documentation for the repair?Thank you all for your time in advance!

author: joeqsmith
author_rank: Super Contributor
timestamp: January 24, 2016, 08:15:53 pm
content: >How reliable is it for bench operation only?Difficult to know what you do on your bench.>How much drift should i expect after 1 year? What about 5?Good question. The two I have purchased only lasted a few hours after removing them from the box.>Can i calibrate it once it drifts?I assume you mean align it and I would doubt it.>When something eventually goes poof! and releases the magic ghost, how likely am i to find the necessary parts and documentation for the repair?These meters are what I would consider disposable. The two I damaged took out the control IC and I was unable to do anything with them. Some of the meters I have tested had enough protection to at least save the main controller. These I have been able to repair.The PCB shown appears to be the same as what I had ran. Notice the two unpopulated clamps. I do wonder if the controller IC would have survived if these were populated but those four diodes cost money!

author: adrianf88
author_rank: Contributor
timestamp: January 24, 2016, 08:26:06 pm
content: What i do on the bench is mainly hobby type stuff, amps, led's, repair broken stuff around the house (monitors, tv, etc) stuff like that.What did you do to them that they only lasted 2 hours?I know the term calibrate, i have 0 ideea what you mean by align.Well, do you have any ideea what diodes were supposed to go there? If so, we can add them on our own.

author: joeqsmith
author_rank: Super Contributor
timestamp: January 24, 2016, 08:47:21 pm
content: If you are playing with line voltage stuff and you have some sort of clamp and breaker, the meter itself should be alright if you know what your doing.The two I had were purchased for the purpose of attempting to see how robust they were. They were both tested to failure and were not repairable.In my own neck of the woods, Calibration is going to be verifying that the equipment is within the manufactures tolerances using some traceable means. If the equipment is out of calibration, we would have it Aligned to bring it back into tolerance.I would guess they would have used the same parts that were used for the other clamp but I would NOT recommend that ANYONE would EVER attempt to make ANY changes to a meter they plan to use for ANY high energy work!!!

author: adrianf88
author_rank: Contributor
timestamp: January 24, 2016, 09:36:47 pm
content: Yeap... I would most definitely do some mains stuff... Testing live wires mostly... But not just sticking the probes in the outlet for the kicksHence the need for NCV but anything more than that, i don't think so.But still some questions remain...How reliable is it for bench operation only?How much drift should i expect after 1 year? What about 5?

author: adrianf88
author_rank: Contributor
timestamp: January 25, 2016, 05:53:14 pm
content: Guess what... I bit the bullet and i bought it... I'm the proud owner of a brand spanking new Uni-T UT139C and i love it. I'll just have to see if it was worth the money in the long run...

author: john_p_wi
author_rank: Regular Contributor
timestamp: January 25, 2016, 06:27:23 pm
content: Adrian, I'm sure it will be fine as long as you don't do something stupid with it.I bought one from Franky over the Holidays and it seems to be a great little meter for general bench use. So far I have only used it in concert with other meters in the development of a low voltage tube filament soft start supply with LED go - no go indication. The only complaints that I have so far are 1) It shuts itself off too quickly and 2) the resistance reading update time is slooow. That is OK, I'll just use one of my Flukes for resistance measurements.Actually, I'll probably order another with a set of mini clips - it is just too handy for general bench use.

author: Simon1983
author_rank: Newbie
timestamp: February 15, 2016, 10:29:08 pm
content: I also got an 139C some month ago. I already had an Ut81B (the scopemeter) ansd it worked well, but was replaced with a Rigol DS1054z. The 81B is still in use for work at cars, where a scopemeter is handy. On the bench I only use it because it runs from mains over the power plug.But I really love the UT139C. Is has fast display update speed, good continuity tester, ans its the first UNI-T I own thas really has input protection and big fuses. The only small drawback (as already mentioned) is the auto-off feature. Yes, and if you would want to calibrate it and adjust it to your reference, you can't: No pots in there, just an eeprom which (possibly) stores the calibration data. The UT81B has pots and I trimmed them to match the UT139C so I would have matching meters (good when using both meters in one circuit).

author: mos6502
author_rank: Frequent Contributor
timestamp: February 16, 2016, 04:42:38 am
content: You can disable the auto-off feature. Hold select while turning the meter on.

author: Martini
author_rank: Regular Contributor
timestamp: March 26, 2016, 03:13:33 pm
content: Hey!I'm probably going to pull the trigger on a UT139C in the coming days. I found it listed at 33 € shipped and that seems very reasonnable compared to a Vichy VC99.I don't think I'll miss the bargraph. One thing I'll miss, though, is the carrying pouch. Any advice on where to find one? Or keywords for the eBay/aliexpress search?

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: March 26, 2016, 03:49:22 pm
content: Quote from: Martini on March 26, 2016, 03:13:33 pmI sell one in my eBay store which fits the UT139C rather well:http://www.ebay.com/itm/Double-Layer-Zipper-Carrying-Case-Bag-for-Multimeters-Fits-UT61E-Fluke-87V-/171047385726

author: freebil
author_rank: Regular Contributor
timestamp: May 13, 2016, 02:39:47 pm
content: Hello. I would like to buy the ut-139 but I saw that it can measure frequency up to 10Mhz. The ut-61e can measure up to 220Mhz I think. The difference is big but maybe I will go with ut-139c because of the protection and its nvc.As I read here its board has different versions and the last version is the fourth. Are there any differences between the versions? May I assume that the last version is better? ThanksQuote from: mematyi on October 03, 2015, 02:30:46 pmI think this link is useful:http://www.kerrywong.com/2016/03/19/hacking-dtm0660l-based-multimeters/

author: Tainer
author_rank: Contributor
timestamp: May 14, 2016, 02:51:16 pm
content: Quote from: freebil on May 13, 2016, 02:39:47 pmI can't tell you about different versions, but if you're planning to buy this meter then keep in mind that frequency measurement will only work if the signal has no DC offset. For instance, you won't be able to measure a 0-3.3V PWM from microcontroller and so on. You'll have to AC-couple the signal with an external capacitor.

author: freebil
author_rank: Regular Contributor
timestamp: May 14, 2016, 04:02:21 pm
content: Quote from: Tainer on May 14, 2016, 02:51:16 pmThanks for the answer. Can ut61e measure it if it has DC offset?

author: Tainer
author_rank: Contributor
timestamp: May 14, 2016, 05:12:45 pm
content: Quote from: freebil on May 14, 2016, 04:02:21 pmI don't have a 61E, but user manual says "Input amplitude: (DC electric level is zero)", so I presume the answer is no.

author: freebil
author_rank: Regular Contributor
timestamp: May 16, 2016, 01:45:30 pm
content: Ok! I pulled the trigger and I ordered one! Are there any alligator clips that can be used with the probes? Maybethese? Thanks.

author: pmason
author_rank: Newbie
timestamp: July 03, 2016, 03:21:32 pm
content: Quote from: freebil on May 16, 2016, 01:45:30 pmI just received mine from China yesterday. I don't know of any alligator clips that are going to work with the probes. Just buy a set of alligator test leads.The UT139c feels very good in the hands, and I really like the ability to snap the probes into the back of the case.The probes are not sharp though.

author: hugatry
author_rank: Contributor
timestamp: July 03, 2016, 03:44:47 pm
content: Quote from: freebil on May 16, 2016, 01:45:30 pmThose need leads that have 4mm banana plugs on both ends. I haven't tested, buttheseshould work with the probes that came with the meter.

author: freebil
author_rank: Regular Contributor
timestamp: July 05, 2016, 09:49:09 am
content: Anyone with 5th revision of the board? Or the last revision is 4?

author: electrifying
author_rank: Newbie
timestamp: July 28, 2016, 10:28:07 am
content: What about the current clamp? Does anyone of you have a current clamp for this meter? And if so, where did you buy it? I have been looking around ebay now but the current clamps I can find cost more than the multimeter itself and mostly have a BNC connector. Am I just using the wrong search phrase? The link to a clamp on Amazon from earlier in this thread sais "currently not available". What's the purpose of the clamp connection if it's cheaper to just buy a complete clamp meter instead of an external clamp for the multimeter?

author: crazyguy
author_rank: Regular Contributor
timestamp: July 28, 2016, 02:19:11 pm
content: MS3302 Digital AC Clamp Meterhttp://www.p-mastech.com/product/detail/392

author: electrifying
author_rank: Newbie
timestamp: July 29, 2016, 08:13:26 am
content: That one would probably work, but only for AC by the looks of it. I would like to have a clamp that can also measure DC. I think it must have hall-effect sensors to measure DC. Strange that UNI-T does'nt offer any clamp at all when they advertise that the meter can be used with a "optional current clamp". I bought the meter thinking that I would just buy a clamp for it as soon as I need one... Maybe they are afraid that offering a reasonable current clamp for the UT139C could ruin the sale of their clamp meters...?

author: classical
author_rank: Regular Contributor
timestamp: July 29, 2016, 09:39:13 am
content: Sensitive DC clampmeters are not cheap and have to be "calibrated" directly before andin the place of the measrement to compensate the magnetic field of the earth.Some years ago a bougt a CA 60 from German ELV.de for about 70 EUR. It is "just" a converter i-> u with 1 mV/10 mA: up to 2 A or 1 mV/100 mA for i> 2 A. You need an additional Multimeter or a scope.If you need 10 times higher resolution next would be Chauvin Arnoux E3N or K1 about 400 to 500 EUR.

author: freebil
author_rank: Regular Contributor
timestamp: August 23, 2016, 08:29:41 pm
content: Hello. The 2 fuses are blown now. Where I can find cheap alternatives? I see that the one is 6X32mm(600V, 600mA) and the other 6x25mm(600V, 10A). I found some 250V and maybe I will go with them. The glass fuses are far inferior to ceramic?

author: cpalha
author_rank: Newbie
timestamp: December 14, 2016, 09:35:14 pm
content: Hi friendsRecently I buy one UT139c from ebay.But has a problem with temperature measurement, when I compare teperature measuremente, the UT139c, gives less 8ºc from reality.I check with other k thermocouple, but the difference are the same, and there is no polarity change.What I can do with this problem? The guy from ebay sais that can refund, but it is only the temperature.Any ideas to resolve this problem? This ut139c has some temperature sensor inside that can be damaged?I would prefer try to resolve the problem or change for a newone, but from ebay seems the only solution will be the refund, and this way is no fair to the seller.Best regardscp

author: Macbeth
author_rank: Super Contributor
timestamp: December 14, 2016, 09:43:45 pm
content: Quote from: cpalha on December 14, 2016, 09:35:14 pmThere is likely a trimmer inside to calibrate the temp. In fact I've found many DMM's with 2 trimmers, 1 for each scale C or F, which is absurd. (Oh are you sure you are reading the correct units C or F?)If all the other functions on the meter appear in good calibration then a twiddle of one of these trimmers while your K probe is in the vicinity of a known good thermometer is probably all you need to fix it.eta: Measuring temps using thermocouples requires a cold junction compensation. In a lot of hand helds this will just be hard-coded to a typical 25 celcius lab temp. If your environment is hotter or colder than this then that is why you have a problem.

author: cpalha
author_rank: Newbie
timestamp: December 15, 2016, 09:05:29 am
content: Hi MacbethThanks for the answear.I compared the measure in degrees celcius with a good thermometer from my lab.In page (6) of this thread we can see the pcb board inside the ut139c and i dont see the trimmers, but i will open it.best regardscpalha

author: Kbird
author_rank: Regular Contributor
timestamp: January 24, 2017, 12:01:17 am
content: Hi , new Member here but I have been reading the Forums for a while and Ordered a Uni-T 61E, for playing around with small projects at home and measure the odd line voltage thing at work, but at least to me it was doing strange things like when auto ranging while measuring AC voltage of an outlet and getting stuck in Manual mode, so I returned it and replaced it with the UT-139C having read about it here too and knowing it was safer for AC measurements anyway since it has 600v Fuses not 250v like the UT-61E . However I am sure the 61E was able to do the Red LED test as can my Old POS DMM I have had for 15-20yrs, but my new 139C doesn't seem to be able too ...or I am doing something wrong ?Is there a good Tutorial on Testing a DMM , incase this one needs to go back too while it can, it seems okay autoranging on AC unlike the 61E ...thanks.Also I always seem to have an issue measuring AC at an Outlet easily , so my thought was to splice a polarised Lamp cord ( so you can't get it wrong) into a set of cheap DMM leads I still have hanging around in the Shop , and use that instead of the probes?.Thanks for your help/commentsKB.

author: totalnoob
author_rank: Regular Contributor
timestamp: January 24, 2017, 01:25:26 pm
content: Not really a tutorial, but if you go to Youtube and look for, I believe its, MLorton he tested a boat load of meters a few years ago and he uses a multimeter test board that he purchased online and goes through each test in those reviews. I believe in one of his videos, or in the comments he tells you where he purchased it from. It contains known values for the various functions that you can test your multimeter against. Without something like that, you are really just guessing as to whether your meter has a problem or not, although you can probably get close enough if you have multiple multimeters that give approximately the same reading.

author: Kbird
author_rank: Regular Contributor
timestamp: January 24, 2017, 09:22:04 pm
content: Thanks Total Noob , I do know MJLorton's Website , so I will have a look there for sure , it is possible there are just functions etc of this meter my old POS DMM doesn't have and I am doing something wrong , it's why I upgraded , it doesn't even have a continuity setting (or buzzer) and I wanted to play around with Arduino etc as well as Household Repairs etc.https://www.youtube.com/user/mjlorton

author: Shadowjump
author_rank: Newbie
timestamp: February 09, 2017, 07:47:57 pm
content: I just got it today. Is there any way to keep the backlight on? It turns off so fast that there is no point in turning it on.

author: Kbird
author_rank: Regular Contributor
timestamp: February 09, 2017, 08:56:28 pm
content: Quote from: Shadowjump on February 09, 2017, 07:47:57 pmI just got one too and think 15 secs is too short as well, but the only fix for it is if you are willing to hack the Firmware on the DMM Chip , it has been done by many, more savvy than me thoughsee Kerry Wong's Page about it here..... you don't need to do the whole hack just for the backlight ie adding the IR receiver/sender etc you just need to change the hex file correct and upload it to the chip. you can apparently make it a 8000 or 9000 count meter too.http://www.kerrywong.com/2016/03/19/hacking-dtm0660l-based-multimeters/The audible chirp when using the dial can't be fixed ( needed for continuity buzzer too) but it doesn't bother me like some, I did see a post saying to add some hot glue to the sensor/speaker to lower the volume works though.KB

author: Martini
author_rank: Regular Contributor
timestamp: June 21, 2017, 01:52:44 am
content: Quote from: Kbird on February 09, 2017, 08:56:28 pmGreat!QuoteSad.

author: Kbird
author_rank: Regular Contributor
timestamp: July 14, 2017, 04:39:11 pm
content: Quote from: Martini on June 21, 2017, 01:52:44 amI did end up modding my 139C , with the Help of FrozenFrog over on this thread....https://www.eevblog.com/forum/testgear/uni-t-ut139c-lcd-biasing-(schematics-avail)/msg1165035/#msg1165035KB

author: darmach
author_rank: Newbie
timestamp: July 16, 2017, 03:10:07 pm
content: Guys, I'm looking for a new mmeter - this or Uni-t UT61D? Why?Im interested in precision, reliability and speed .)I can also buy an used Metex M-3850D similar price, maybe that?

author: Kbird
author_rank: Regular Contributor
timestamp: July 16, 2017, 04:58:45 pm
content: Quote from: darmach on July 16, 2017, 03:10:07 pmI am no expert on MMeters ( or electronics) but I returned my 61E ( getting stuck in autorange it seemed) and got the 139C ( safer for mains voltage which I wanted) and am happy with it so far, and recently picked up the UT-210E mini Clamp meter to complement it too. And I have now hacked both based on posts here (and elsewhere) to add/change a few features.more info on that herehttps://www.eevblog.com/forum/testgear/a-look-at-the-uni-t-ut210e/andhttps://www.eevblog.com/forum/testgear/uni-t-ut139c-lcd-biasing-(schematics-avail)/new/?topicseen#new

author: darmach
author_rank: Newbie
timestamp: July 16, 2017, 06:49:15 pm
content: Quote from: Kbird on July 16, 2017, 04:58:45 pmAnd how do you felt the quality, and working with them? Which one seem to be faster, more convenient?

author: Kbird
author_rank: Regular Contributor
timestamp: July 16, 2017, 08:56:44 pm
content: Quote from: darmach on July 16, 2017, 06:49:15 pmI did not have the 61E long but they seem about the same from what I remember , I am happy with the 139C , i have used it alot on the Bench , modifying so old Gameport Joysticks and throttles to USB and messing with Arduino etc and also at Work to check Voltages and Temperature to which was handy.the 210E wouldn't be a good Bench MMeter, but is handy if you work on Vehicles etc too or want to check Appliances etc with the Clamp .I don't know the Metex at all , perhaps some-else will post about that, perhaps it's a good buy ? though if you need Data logging it and the 61E are the only two to do it. there is an old post on that meter from 2013 I just found here :https://www.eevblog.com/forum/testgear/metex-m-3850-dmm-good/If you want a cheaper meter ($20-25) to play with or as a backup to your main MMeter , there is alot of talk about the AN8008 in this thread :https://www.eevblog.com/forum/testgear/an8008-us-$19-10000count-1uv-0-01ua-0-01ohm-resolution-meter/

author: MosherIV
author_rank: Super Contributor
timestamp: July 16, 2017, 11:33:25 pm
content: QuoteGo with the UT139 for your new meter.If you truely are after precision, you should be looking much more up market - 4 digit meters and above. Now you are into bench meter territory, which generally are not as reobust as the hand helds.Also, precision and speed do not generally go together. You either want precisionand accuracy and are prepared to wait for the measurement (though now a days they take 10+ measurements a second) or you want speed and sacrifice precision/accuracy.

author: darmach
author_rank: Newbie
timestamp: July 17, 2017, 05:06:16 am
content: Quote from: MosherIV on July 16, 2017, 11:33:25 pmAh, that's a very good advice. Most likely I wanted a holy grail then! .) Thank you!

author: darmach
author_rank: Newbie
timestamp: July 20, 2017, 06:24:52 am
content: Quote from: Legit-Design on September 09, 2013, 11:46:55 pmHi, you wrote that you have both ut139c and ut61E. Can you compare autoranging speed between them? Measurement speed? I'm torn between these two.

author: hans_ober
author_rank: Newbie
timestamp: July 29, 2017, 05:12:45 pm
content: Was considering purchasing this meter based on all the reviews I've read. I'm an EE student, and will use it for hobbyist electronics work, plus electrical work around the house (and fixing electrical stuff).I was looking for an Autoranging True RMS meter in general. Most often used functions would be Voltage and Continuity test (which is fast on the 139C from what I've read). Backlight and Temperature weren't essential, but nice to have.I'd like a Peak/ Min-Max mode that I could use to calculate the Crest/Peak factor of AC Mains voltage.What's the difference between the Peak function on the UT-61E and the Min/Max on the 139C?Will the Min/Max on the 139C show me the peak of a sine wave: 230 * 1.414 = ~320V(assuming a crest factor of 1.414 for a perfect sine wave)?

author: Martini
author_rank: Regular Contributor
timestamp: February 04, 2018, 01:49:21 pm
content: Quote from: hans_ober on July 29, 2017, 05:12:45 pmNo. It will display 0V or close.EDIT: I have a question myself: which clamp can you use with it? Will it do DC current?

author: Kbird
author_rank: Regular Contributor
timestamp: February 04, 2018, 07:30:26 pm
content: Quote from: Martini on February 04, 2018, 01:49:21 pmI ended up just getting the 210E and Modding it too since it was basically the same cost as an addon clamp but also gives me a 2nd Meter to Test with/compare , if needed.KB

author: Martini
author_rank: Regular Contributor
timestamp: February 04, 2018, 08:32:17 pm
content: Well, the 139C has the min/max function

author: Kbird
author_rank: Regular Contributor
timestamp: February 04, 2018, 09:13:52 pm
content: I meant I got a 139C AND a 210E = best of both worlds... not just a 210E , I got the 210E instead of an addon Clamp for the 139C as it was only a few $$ more at that time and it gave me a 2nd Meter for backup .... the new 210E have a slightly better Chip now I believe.

author: Martini
author_rank: Regular Contributor
timestamp: February 04, 2018, 10:00:42 pm
content: Do you remember the clamp add-on reference?

author: Kbird
author_rank: Regular Contributor
timestamp: February 04, 2018, 10:34:27 pm
content: I don't sorry AFAIK Uni-T never made one but I believe it is limited to 60Amp on the 139C. I think the Cheapest I found was $38 which made the 210E a no brainer for me...something like these perhaps.... I do not have or recommend either of them ,,,I just had a quick look on Amazon...perhaps wait for more replieshttps://www.amazon.ca/dp/B00X3GDVWM/ref=sxbs_sxwds-stvpv2_1?pf_rd_m=A3DWYIK6Y9EEQB&pf_rd_p=3443526782&pd_rd_wg=Yfik6&pf_rd_r=BW2MG6BEH2YSDJBH6NNY&pf_rd_s=desktop-sx-bottom-slot&pf_rd_t=301&pd_rd_i=B00X3GDVWM&pd_rd_w=vVV3m&pf_rd_i=Clamp+Meter&pd_rd_r=0008d437-3747-4a38-bbb2-f1fe132dd42c&ie=UTF8&qid=1517782789&sr=1https://www.amazon.ca/all-sun-Current-Working-Multimeter-Measurement/product-reviews/B013QH4K86/ref=dpx_acr_txt?showViewpoints=1

author: Martini
author_rank: Regular Contributor
timestamp: February 04, 2018, 11:44:47 pm
content: Clamp add-on seems like a shitty idea suddenly.

author: carnage
author_rank: Regular Contributor
timestamp: October 25, 2018, 01:37:27 pm
content: Has anyone tried using Energizer Ultimate Lithium in the UT139C?Did it work properly?

author: Kbird
author_rank: Regular Contributor
timestamp: October 25, 2018, 04:51:09 pm
content: Have not tried them in the 139CBut I have/had them in a logitech mouse and they do strange things...one will drain to almost 0v (0.404v) and the mouse becomes erratic as expected but if I leave the batteries out on the Workbench, a day or two later the battery is back to full Voltage.....has happened twice now but I am not using it in my Old Mouse any longer.... not sure if it is a drainage issue or what?

author: carnage
author_rank: Regular Contributor
timestamp: October 28, 2018, 11:34:20 am
content: Quote from: Kbird on October 25, 2018, 04:51:09 pmI read that there was some Brymen meter don't like Energizer Ultimate Lithium.Thanks for the reply!

author: Kbird
author_rank: Regular Contributor
timestamp: October 28, 2018, 04:16:54 pm
content: Quote from: carnage on October 28, 2018, 11:34:20 amNow I am curious ......what was happening with the Brymen?The Lithium start out at high voltage .... like 1.78-1.81v .... the 2 I have used a while are in the 1.54-1.56 range though..

author: carnage
author_rank: Regular Contributor
timestamp: October 28, 2018, 09:57:34 pm
content: Quote from: Kbird on October 28, 2018, 04:16:54 pmHere's the link where I read about the Brymenhttps://www.eevblog.com/forum/testgear/the-bm235-does-not-accept-lithium-batteries/

author: Kbird
author_rank: Regular Contributor
timestamp: October 29, 2018, 12:10:21 am
content: Thanks for the Link Carnage*** looks like I was right about the initial 1.8v+ being too high (Over 3.6v total) when new....However I am unsure if the 139C has the same limitation?KB.

author: carnage
author_rank: Regular Contributor
timestamp: October 29, 2018, 01:55:53 pm
content: Can it cause any damage to the meter if I use the Energizer Ultimate Lithium?Does the meter has any protection if the batteries has a higher voltage than what it call for?

author: Kbird
author_rank: Regular Contributor
timestamp: October 29, 2018, 06:27:47 pm
content: Quote from: carnage on October 29, 2018, 01:55:53 pmI don't know sorry and as far as I have read the Manual does not mention Over-voltage on the Battery Power at all. ( may have missed it?)Lower Battery Pwr warning light is 2.4v and the Meter will not work below 2.2v ( backlight may not work below 2.6v or be dim)

author: carnage
author_rank: Regular Contributor
timestamp: October 30, 2018, 11:34:35 am
content: Will the Eneloop Pro work or any NiMH at 1.2V?What are you using for batteries in your Uni-T UT139C?

author: Kbird
author_rank: Regular Contributor
timestamp: October 30, 2018, 06:09:51 pm
content: Quote from: carnage on October 30, 2018, 11:34:35 amJust standard AA Energizer currently , also use the Duracell AAI have had issues over the years with NiMh 1.2v cells in different devices eg Camera gear etc , so I avoid them nowadays. I do have some 1.5v+ Pure Energy Rechargables but was worried about leakage as the Batts sit along time in a Meter so I didn't use them.According to the Specs at 2.4v it will work but I am not sure if accuracy is effect as it turns off at 2.2v according to the Specs.Perhaps try emailing Uni-T and ask for more details especially the Upper limit and if you can use the 1.8v Lithiums...KB.

author: carnage
author_rank: Regular Contributor
timestamp: October 30, 2018, 10:31:40 pm
content: Quote from: Kbird on October 30, 2018, 06:09:51 pmI have the Energizer Max I probably going to use if I can't find anything else to use. I had to many Duracell leak in my devices to use them.Look like my Eneloops aren't going to work.I tried emailing Uni-T twice with no reply.I also tried emailing the seller, I'm just waiting for a reply.Is there a Uni-T in the U.S.?

author: Kbird
author_rank: Regular Contributor
timestamp: October 30, 2018, 10:45:43 pm
content: Not as far as I know , there is a Nth American Sales link , maybe worth a try?Neo Chen - North/South America & AustraliaTel: (86-769) 8572 3888-306Email: neo@uni-trend.com.cn

author: carnage
author_rank: Regular Contributor
timestamp: October 30, 2018, 11:32:40 pm
content: Quote from: Kbird on October 30, 2018, 10:45:43 pmI just sent him a email.Thanks for all of the replies! I'll let you know what he said if I get a reply.

author: carnage
author_rank: Regular Contributor
timestamp: October 31, 2018, 11:35:36 am
content: I got a reply from the seller. He said to use Zinc Carbon batteries.I had to Google Zinc Carbon batteries to see what it is and if it available.Does Zinc Carbon have or hold more power than alkaline and do they leak?

author: HKJ
author_rank: Super Contributor
timestamp: October 31, 2018, 11:50:17 am
content: Quote from: carnage on October 31, 2018, 11:35:36 amZinc Carbon is about 1/3 the energy of Alkaline and cannot deliver very high power, I have published a few test of them.They are worse than alkaline with leaks.

author: carnage
author_rank: Regular Contributor
timestamp: November 01, 2018, 12:08:58 pm
content: Quote from: HKJ on October 31, 2018, 11:50:17 amThanks for the reply HKJ!Do you think it would be safe to try Energizer Ultimate Lithium in the UT139C without any issue? Like shorting out something.

author: HKJ
author_rank: Super Contributor
timestamp: November 01, 2018, 12:16:40 pm
content: Quote from: carnage on November 01, 2018, 12:08:58 pmI would expect so, the DMM chip is rated for 3.6V operating and 4V maximum.

author: carnage
author_rank: Regular Contributor
timestamp: November 02, 2018, 10:32:58 am
content: Quote from: HKJ on November 01, 2018, 12:16:40 pmThanks for the reply HKJ!I'm going to get a pack of Ultimate Lithium.

author: Kbird
author_rank: Regular Contributor
timestamp: November 02, 2018, 04:16:12 pm
content: Quote from: carnage on November 02, 2018, 10:32:58 amIf you have the same issue as the Brymen , then run them down to 1.6v in a flashlight and they should be fine , fresh my last pact was 1.82 or higher.Post back please and let us know how it goes, thx.KB.

author: soren
author_rank: Regular Contributor
timestamp: March 11, 2019, 03:54:21 pm
content: An unbranded version of the UT139C is currently on sale via Amazon Europe for EUR 10.99.https://www.amazon.de/dp/B077ZQS94Khttps://www.amazon.fr/dp/B077ZQS94Khttps://www.amazon.es/dp/B077ZQS94KI just received one and everything including probes and manual appear to be exactly like with the UT139C, except without the Uni-T name. If it's a clone, it is an extremely faithful one.

author: rsjsouza
author_rank: Super Contributor
timestamp: March 11, 2019, 06:26:47 pm
content: US$16.99 at Amazon.com with prime free shippinghttps://www.amazon.com/Multimeter-Voltmeter-Ohmmeter-Temperature-Measurement/dp/B077ZQ2Z5S

author: stj
author_rank: Super Contributor
timestamp: March 12, 2019, 01:24:57 am
content: i dont have a 139c, but if it uses the 0660 chip like the 210e or the aneng meters then it will run on eneloops etc.i have been using ladda's in my 210e and 2 aneng's for over a year without problems.

author: TheNewLab
author_rank: Frequent Contributor
timestamp: March 12, 2019, 02:03:07 am
content: hmmmm, interesting the US Amazon shows $22 USDhttps://www.amazon.com/dp/B0194VGLFS?aaxitk=U1Y6brI3NcyHLqKAr8U4cA&pd_rd_i=B0194VGLFS&pf_rd_p=e037c154-e093-48a4-b127-477e5e294e3f&hsa_cr_id=7814473900601&sb-ci-n=productDescription&sb-ci-v=Proster%20PSTTL334%20Digital%20Multimeter%206000%20Counts%20TRMS%20Auto%20Range%20NCV%20Detector%20DC%20AC%20Voltage%20Current%20Meter%20Temperature%20Capacitance%20Diode%20and%20Continuity%20Tester%2C%20Manual&sb-ci-a=B0194VGLFS

author: rsjsouza
author_rank: Super Contributor
timestamp: March 12, 2019, 03:17:47 am
content: This is a completely different meter.

author: rsjsouza
author_rank: Super Contributor
timestamp: March 12, 2019, 04:37:59 pm
content: Wow... Amazon delivered it in about 24h. I wonder if this was just around the corner from here.It really looks the real deal. It even has the Intertek listing number, although on a sticker and not indelllible.I did not open it yet. Will do at the first opportunity.

author: hli
author_rank: Frequent Contributor
timestamp: March 14, 2019, 08:11:30 pm
content: Quote from: soren on March 11, 2019, 03:54:21 pmGot mine from the german Amazon - 10.99 EUR delivered. Opened it up, and the PCB says 'UT139C' (look at the right side in yout photo). Compared to my older ones the PCB looks a little bit different. From the silkscrren it looks the old ones are at PCB revision -1 and the new one is at -4.When I look at the product page now its at 39.99 EUR. So it seems to be a mistake on the sellers part...

author: rsjsouza
author_rank: Super Contributor
timestamp: March 14, 2019, 08:17:21 pm
content: Quote from: hli on March 14, 2019, 08:11:30 pmI opened mine and can attest it is a UT139C - same markings as yours, good input protection and excellent build quality. I even connected its inputs (ohm, continuity, diode, temperature, frequency) to a high voltage source and the meter did not even blink - a hint that the input protection is doing its work in protecting the meter.Amazon US still has it for US$16.99 with Free shipping.

author: rogbese
author_rank: Newbie
timestamp: October 13, 2020, 11:43:39 am
content: Hello!Sorry to dredge up an old post. I just got this meter after reading thru this and was wondering on this new revision 5 board. The main chip is conned(?) and the location of the interface pins is different. I also notice an led? I'm thinking maybe a shared board? From others' experience, how good is this dmm in 2020 compared to the ut89x for bench work and basic home work?

author: Fretec
author_rank: Contributor
timestamp: October 13, 2020, 03:22:44 pm
content: Quote from: carnage on October 31, 2018, 11:35:36 amZinc Carbon, really? I wonder where he got this information from... This is ancient battery technology far inferior to alcaline (and everything else made these days).Not sure if you can even still buy them, have not seen any for a long time.