Aliexpress bargain alert- WinApex 268B AC/DC clamp meter - Page 1
Forum section: electronics / testgear

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 12, 2024, 06:21:16 pm
content: I've had one of these for a while but now listed at 50% off ( may vary by country) - absolute bargain at that price.https://www.aliexpress.com/item/1005006583519373.html1mA resolution on clamp DCA, 0.1mA on ACA - ideal for earth leakage measurements.Really bright, big display, USB rechargeable.

author: thm_w
author_rank: Super Contributor
timestamp: July 12, 2024, 10:50:31 pm
content: Review:4% off in DC mode low current. I think the UT210e is a bit more accurate at DC, but this has a wider range of 6A.Cheaper here for me $33 shipped:https://www.aliexpress.com/item/1005006582824997.html

author: rsjsouza
author_rank: Super Contributor
timestamp: July 12, 2024, 11:29:54 pm
content: Interestingly a few weeks ago I was looking into the whole leakage clamps at Ali. That is a pretty interesting offer for the price; thanks Mike!

author: Hydron
author_rank: Super Contributor
timestamp: July 14, 2024, 11:55:04 am
content: Has anyone opened one up? Wonder how they're safely doing USB recharge. And thanks Mike!

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 14, 2024, 12:06:47 pm
content: Don't think usb is isolated,but socket is recessed so it's pretty hard to touch, and the unit doesn't operate if charging.

author: wraper
author_rank: Unknown
timestamp: July 14, 2024, 12:10:53 pm
content: A little bit cheaper here considering free shipping (at least for me).https://vi.aliexpress.com/item/1005006582824997.html

author: Aldo22
author_rank: Super Contributor
timestamp: July 14, 2024, 02:41:49 pm
content: Has anyone tested this device below 100mA DC?I have anANENG ST212and it is getting unstable and inaccurate below 100mA.Is this one better?In the video you can only see 500mA.

author: wasedadoc
author_rank: Super Contributor
timestamp: July 14, 2024, 06:03:14 pm
content: Quote from: thm_w on July 12, 2024, 10:50:31 pmThat reviewer was clueless about using a clamp meter to measure direct current.

author: Phil1977
author_rank: Frequent Contributor
timestamp: July 14, 2024, 08:20:30 pm
content: I have this meter, it´s not too bad.DC resolution is real, but accuracy is bad compared to shunt meters. It means, if you can place the clamp, zero it and do not touch it anymore then you can see small current changes.By best guess I´d say accuracy is +/- 2.5% plus +/- 50mA in the DC current mode.It´s also not very resilient to magnetization. If you expose it to large currents (>50A) or strong magnets, you get quite some hysteresis. I already had the degauss it once.Quote from: Hydron on July 14, 2024, 11:55:04 amWhat do you want to know? I´m quite sure it´s not galvanically isolated to the probe jacks. But the plug is deeply recessed and covered by a tightly fitting and not detachable rubber cap. I did not check if the charging circuit is safe for the LiPo-pouch but just in case this is easily accessible and has a standard plug.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 14, 2024, 08:46:42 pm
content: All DC clamp meters are inherently inaccurate at low currents, as they are affected by any stray magnetic field, including Earth's, so are somewhat position dependent.You need to understand how to use them properly to get the best performance - ideally set it up and zero in the final position with the test subject's power off, then power on without moving the clamp. After measuring, power off and verify that the reading returns to zero. Obviously this isn't always practical, so you need to bear in mind any inaccuracy caused.Any movement between where you zero and the measurement position will cause errors.

author: Fungus
author_rank: Super Contributor
timestamp: July 14, 2024, 09:27:48 pm
content: Not always practical, but:You can also wrap the wire around the clamp a few times and get more accuracy that way.eg. wrap it around 10x and divide the result by 10.

author: Martin72
author_rank: Super Contributor
timestamp: July 14, 2024, 09:51:03 pm
content: Quote from: mikeselectricstuff on July 14, 2024, 08:46:42 pmIn this context, I am somewhat surprised that even higher-priced current clamps do not use the compensation method that prevents the core from magnetizing (at least as long as the current clamp is not "overrun").

author: Aldo22
author_rank: Super Contributor
timestamp: July 15, 2024, 08:23:10 am
content: Quote from: Fungus on July 14, 2024, 09:27:48 pmThank you, that helps with low currents.What bothers me about my ANENG ST212 is that it does not display a stable value.It constantly changes the measurement display, e.g. in the range from 0.95A to 1.05A, without changing anything in the measurement setup.These measurements are probably even in the specified range ± (2.5% +8d) for DC current, but difficult to read in this way.With averaging, the measurement might quite accurate. But the way it is, you have to estimate from the changing values.But at least it is "honest" and shows you the uncertainty.The WinApex 268B seems a bit more stable.

author: Phil1977
author_rank: Frequent Contributor
timestamp: July 15, 2024, 08:43:07 am
content: If you want to have a look inside:The cyan clamp housing is glued so I couldn't get a glimpse on the magnetic sensor. The thin green wire going from the main IC blop to the clamp is probably the NCV antenna.There are two trimming potentiometers - so maybe recalibration of the clamp is feasible.A small annoyance is that the "ZERO" button only works in DC amps.

author: wasedadoc
author_rank: Super Contributor
timestamp: July 15, 2024, 09:58:10 am
content: Quote from: Phil1977 on July 15, 2024, 08:43:07 amThe zero button on any clamp meter is to subtract the ambient magnetic field. Earth's field and nearby magnetised objects. That should be a steady offset. When measuring AC that offset is removed by an AC coupling or software. Have you ever seen a "zero" button on a clamp meter which does not measure direct current?

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 15, 2024, 10:26:26 am
content: Quote from: wasedadoc on July 15, 2024, 09:58:10 amThe offset is often done in the analogue domain as offsets can be large compared to the measuring range

author: Phil1977
author_rank: Frequent Contributor
timestamp: July 15, 2024, 10:35:00 am
content: Yes,Quote from: mikeselectricstuff on July 15, 2024, 10:26:26 amYes, thank you, this probably is the reason. But anyhow, the "Zero"-Button is handled by the microcontroller, so it would just have meant a few additional lines of code to make it a "REL"-button in the other ranges.

author: thm_w
author_rank: Super Contributor
timestamp: July 15, 2024, 10:56:19 pm
content: Zero button on UT210e works on both DC and AC, for reference.

author: Martin72
author_rank: Super Contributor
timestamp: July 15, 2024, 11:29:38 pm
content: Yes, this is simply a REL function.

author: DaneLaw
author_rank: Frequent Contributor
timestamp: July 16, 2024, 04:29:25 pm
content: Quote from: mikeselectricstuff on July 12, 2024, 06:21:16 pmTake Aliexpress "discount percentages" with a pinch of salt, they are often tainted to create purchase incentive.. its been between 30 to 40 dollars (incl. 20/25% VAT (EU) for the last year)Same with other sources like Banggood... Highest price was 36.99 back in mid-2023 (3Q) lowest price were around 28.99 USD (incl. EU VAT) a few weeks back.Price-evolvement graph Winapex 268B.Price evolvement info grapped from:https://couponsfromchina.com/winapex-268b-leakage-current-detect-clamp-meter-discount-price/Talked about it here on EEVblog ½ year back,as i puzzled about taken the plunge, but after seeing some feedback, I took a pass - as it seemed like a step back (already have an 210E)https://www.eevblog.com/forum/testgear/good-clamp-meter-for-low-dc-currents/msg5347925/#msg5347925

author: Phil1977
author_rank: Frequent Contributor
timestamp: July 16, 2024, 06:37:04 pm
content: I´ve done a quick test with the WinApex and a Peaktech 4250. It´s somehow unfair because the Peaktech 4250 has a much smaller clamp area, which reduces influence of external magnetic fields. The Peaktech was never calibrated, so it has the most stable values but quite some systematic deviation.Continous means that the cable was inserted into the clamp and zeroed while no current was flowing.Single means the clamp was each time zeroed while empty and then put over the active cable.Tabelle.txt(2.63 kB - downloaded 47 times.)

author: vele64
author_rank: Newbie
timestamp: November 08, 2024, 10:15:01 pm
content: Does anyone have manual of WinApex 268B?I've searched everywhere but in vain... :'(

author: popy5
author_rank: Contributor
timestamp: December 18, 2024, 03:53:21 pm
content: I scanned it... not with great quality, but it works.

author: morgan_flint
author_rank: Regular Contributor
timestamp: March 05, 2025, 12:26:10 pm
content: Does somebody know or can test if it's true RMS?I didn't see anything about that in the specs listed in the advertisements, but I imagine all these specialized microcontroller-based meters can do that for almost free...EDIT: I just saw in the manual posted by @popy5, in section 2 "AC Voltage (ACV) RMS": "Frequency response:True RMS measurable: Sine wave, triangular wave (40-1000) Hz, other waveforms (40-200) Hz;"It's a bit ambiguous, and it doesn't say anything equivalent in AC current, so I'm not still very sure if this is a TRMS meter... Chinese specs tend to be "generous", so not mentioning it is a bad symptom

author: HighVoltage
author_rank: Super Contributor
timestamp: March 05, 2025, 12:44:50 pm
content: Best price I found was 29,39€ with 50% discount.Lately all AliExpress orders have arrived at my place in Germany within a week of ordering.Sometimes faster than eBay Germany.

author: morgan_flint
author_rank: Regular Contributor
timestamp: March 06, 2025, 05:23:16 pm
content: Finally, I ordered one for 32.36€ inc shipping from Aliexpress.My main concern was the ability to measure low AC currents for leakage measurements, so the 600mA range in this one was one of the main drivers in the decision to buy it.I also had considered other AC-only clamps, but this one gave DC for only a few more €.I will report when I get it

author: faraday
author_rank: Regular Contributor
timestamp: March 12, 2025, 12:43:01 pm
content: Got one too. It arrived very quickly. About leakage current kettle shows around 2,8mA leakage.

author: Paul T
author_rank: Regular Contributor
timestamp: March 12, 2025, 11:23:29 pm
content: Here's a review which includes some comparison to the Uni-T UT210E.www.keepontesting.com/post/winapex-268b-digital-clamp-multimeter-bonus-materialThe jaws of the unit are a delight to use. However, since the review, I have used the WinAPEX to measure DC current and it wasn't doing quite as well as my original. You can see some more recent results about 2/3 the way through this post:www.keepontesting.com/post/error-chart-compilation-dc-currentI paid US$25 last year, including shipping and taxes.

author: morgan_flint
author_rank: Regular Contributor
timestamp: March 15, 2025, 10:16:39 am
content: Quote from: morgan_flint on March 05, 2025, 12:26:10 pmQuote from: morgan_flint on March 06, 2025, 05:23:16 pmOk, it finally arrived. I have taken some measurements and am happy for now.Regarding true RMS, it is, at least in voltage measurements. I've tested it with 50 and 100 Hz, and with sinusoidal, triangle, and square waves: