Which USB power tester do you recommend? - Page 1
Forum section: electronics / testgear

author: Its wednesday my dudes
author_rank: Contributor
timestamp: May 07, 2023, 11:34:42 am
content: Hi guys,I wanted to get a USB power meter/tester and I am kinda overwhelmed by the mass of mostly cheap looking USB power tester/meters. After looking around I setteled for this onehttps://www.amazon.de/dp/B07DCS11GMI ordered one, tried it on a broken e-reader I intend to fix, and the screen went all fuzzy permanently after connecting the e-reader. I thought I had bad luck, ordered another one and the same problem occured.So I am back again at picking one. My question is what USB power meter/tester you guys are using/recommending and if it has some kinde of short circuit protection (?) to not getting fried, just because a bad device was connected?Thanks a lot for your input!

author: nctnico
author_rank: Super Contributor
timestamp: May 07, 2023, 01:20:23 pm
content: I have this one. Works pretty well.https://joy-it.net/en/products/JT-TC66CYou shouldn't be super concerned about short circuits because USB ports are typically current limited.

author: 4thDoctorWhoFan
author_rank: Regular Contributor
timestamp: May 07, 2023, 02:33:30 pm
content: I have a couple of these CT-3 USB testers and they are nice.https://www.amazon.com/AVHzY-Digital-Multimeter-Detector-26-0000V/dp/B073R7YRM9/ref=sr_1_3?keywords=usb%2Bct3&sr=8-3&th=1

author: BILLPOD
author_rank: Frequent Contributor
timestamp: May 07, 2023, 07:29:08 pm
content: My most used USB Tester is my J7-C, as it is the easiest to control of all of the ones I have, (I try out most as they come out). Most of them have a convoluted control system of push-button and rocker switches, that are NOT intuitive AT ALL. The J7-C takes just 4 clicks of the push-button switch, to navigate it's menu.I also like my UD18, as it is easy to control with my tablet, using Bluetooth

author: ddavidebor
author_rank: Super Contributor
timestamp: May 07, 2023, 08:26:54 pm
content: I have tried many of these as I design and manufacture tablet computers.In my experience, the best are from ChargerLab. the KM003C is the latesthttps://www.chargerlab.comhttps://www.chargerlab.com/introducing-the-brand-new-power-z-km003c/However, this might be overkill for your needs.

author: Its wednesday my dudes
author_rank: Contributor
timestamp: May 08, 2023, 08:22:23 am
content: QuoteThat was just a wild guess from my side, since I saw two USB testers die by just connecting the same bad device.Many thanks to all of you for your suggestions, I will study them.

author: bffargo
author_rank: Regular Contributor
timestamp: May 08, 2023, 06:26:54 pm
content: The UM25C is the best one I've owned so far. No, it doesn't have all the bells and whistles, but seems to have the most accurate and non-randomly fluctuating voltage / current readings. It easily supports 30V.I've tried everything from the old OLED pixeled or fixed segment LCD displays to the IPS tiny color to the newer ones with the shuttle keys. I find that the non-Riden made ones, usually with 5th decimal digit or more, are generally useless due to wide variations in readings and off by more compared to a calibrated DMM. That's why I always go back to the UM25C. Some of the other ones has protocol triggers and detection which is good, but most of my USB work involves plain old 5V.All work in a pinch, and I've hacked a few to serve as inline monitors for things like power tool battery depletion and the like. But for pure USB, I'm happiest with that one.I've spent $3 to $20 maximum (inflation or no coupons available at the time would bring that to probably $26 maximum now) for all of mine. I can't bring myself to pay $30, $50 or more for a USB tester. Perhaps some of those are really good, but look to just be variations on the 38S/48S ones with the low quality "Oscope" function or the high digit counts that provide me no additional value.

author: DaneLaw
author_rank: Frequent Contributor
timestamp: May 08, 2023, 09:36:46 pm
content: Have tried quite a few over the last decade or more of these small USB meter gadgets - some with BT and all that jazz, and some without.. often fitted with so many features that it's starting to be troublesome controlling it all from crude pushbuttons.One USB-meter, I often tend to use a lot, is these round one's below, as they have all the plugs in one, Barrel DC, TypeC, USB3, MicroUSB, temperature, Bluetooth and they were quite cheap around 10 to 15 bucks incl. EU VAT & shipping and the build were good for the price with USB3 socketshttps://lygte-info.dk/pic/USB%20meter/USB%20tester%20Atorch%20UD18%20%28Hidance%29/DSC_0011a.jpgbut somewhat old, like a handful of years back, since they were sold at sites like Bangood.. reviewhttps://lygte-info.dk/review/USBmeter%20USB%20tester%20Atorch%20UD18%20%28Hidance%29%20UK.htmlThe latest one I got is one from Fnirsi. FNB58 with bluetooth and got tons of settings.very polished interface with PD3.1 140w trigger, not sure what the prices was, but I guess it was around 35 to 40 bucks (incl. shipping and 25% danish VAT) so likely cheaper in US...but its mindbending the features that are build into these USB meters, now-a-days.// yep Fnirsi FNB58 around 37 US so not cheaphttps://tinyurl.com/592zaaeubut for the price, suited with tons of features, but likely also too advanced' if you just want some crude USB-meters that give you the basic stats.But decide what main-interface you want.. TypeC or USB-A.. for TypeC the TC64 is a decent very tiny TypeC-meter, but only one current direction for display-reading, though can also be had in a two-way version TC66' that is like more than double the price of the TC64, but take a look on "Lygte-Info" tons of reviews of USB-meters and the features they have and how they perform according to spec.https://lygte-info.dk/info/indexUSB%20UK.html

author: MarkMLl
author_rank: Frequent Contributor
timestamp: July 27, 2023, 05:27:10 pm
content: Quote from: DaneLaw on May 08, 2023, 09:36:46 pmThe link below describes that type of meter being repurposed as a smart charger, which is interesting.https://hackaday.com/2023/01/01/use-usb-c-chargers-to-top-up-li-ion-packs-with-this-hack/However, what I'd like to know is the extent to which that (or for that matter any) type of meter can report what resistors are connected to a peripheral's data and (for mini/micro) ID lines, since (as I understand it) resistors on the D lines announce whether a peripheral is USB v1, v2 or power-only while various resistors on the ID line can informally signal the type of the peripheral (I've seen a list related to I think Samsung that described the options: lots of debugging adapters etc.).The particular reason I'm interested is that I've got a blood pressure meter where the same connector can either be used to connect a pulse oximeter, or for a USB connector to a host. I'd quite like to know what's going on here without taking it to bits...I could obviously do that using an Ardiuno etc. and some analogue switches, but am interested to know what's available before I consider putting time into it.MarkMLl

author: Veteran68
author_rank: Frequent Contributor
timestamp: July 27, 2023, 06:53:26 pm
content: I currently have these:X-Dragon- First one I owned, cheap and simple. One of my dogs somehow got hold of it and took it outside, I found it in the backyard wet and covered in mud. Cleaned it up and it still worked!Klein Tools ET920- The one I've used the most to this point. More sophisticated than the X-Dragon but much less than the Fnirsi FNB58. I like how it has flexible cable leads for both USB-A and USB-C, unlike the unibody testers with a rigid connector, and which require patch cables to use both A and C type connectors. The cable attachment makes it less likely to be bumped or jerked and risk breaking a port or connector.Fnirsi FNB58 (Bluetooth)- Most sophisticated one I own, it has tons of features including waveform display of voltage and noise signals, like a mini oscilloscope. I haven't used this one as much yet as I just got it a couple months ago. Requires a patch cable to use with USB-C devices. Fnirsi does make theC1 modelthat has a USB-C connector, but less features.

author: zerrin
author_rank: Newbie
timestamp: November 21, 2024, 07:20:08 pm
content: You might be interested in this project, USB VSense:https://www.hackster.io/news/usb-vsense-makes-sense-of-all-the-voltages-available-from-usb-c-8fd21a49fbb7https://www.crowdsupply.com/meticulous-technologies/usb-vsense

author: MarkMLl
author_rank: Frequent Contributor
timestamp: January 29, 2025, 08:11:46 pm
content: Quote from: Veteran68 on July 27, 2023, 06:53:26 pmA persistent niggle of mine is that most (Chinese-made) USB voltage/current meters are "upside-down" in relation to most (Chinese-made) PSUs.A few days ago I took a saw to the PCB inside one of the cheap meters in a transparent case and fixed that one...The FNB58 does appear to have a very nice feature set when it comes to power delivery protocol detection. I definitely need to get something along those lines, because apart from anything else I'm concerned that there are PSUs which, if asked to put 24V on one port, will put it on all of them.MarkMLl

author: nctnico
author_rank: Super Contributor
timestamp: January 29, 2025, 09:57:01 pm
content: Quote from: MarkMLl on January 29, 2025, 08:11:46 pmThat would be a gross violation of any USB based power protocol designed to deliver >5V on a port.

author: MarkMLl
author_rank: Frequent Contributor
timestamp: January 30, 2025, 08:51:23 am
content: Quote from: nctnico on January 29, 2025, 09:57:01 pmSo? I can't immediately find the photos I'm looking for, but I've seen (Chinese-made) "solar MPPT USB" modules based on an Injoinic IP6538 chip designed to support either a USB-C plus a single USB-A, or two independent USB-As with several of the power-delivery protocols.Except the manufacturer has added a second USB-A in parallel with the first, in addition to the USB-C.And I've seen a writeup of somebody sticking a couple of those into a homebrew powerbank.Now we're obviously way outside the realm of "Standard USB with logo legitimately attached" here, the designer of the module is way out of line, and the hacker who made the powerbank didn't do her homework and assumed that the stuff she was buying in was OK.https://hackaday.com/2022/11/13/diy-usb-charging-the-right-way/So the next time you see a cluster of USB outlets in a cafe or shop, I suggest you ask yourself what's actually behind it, rather than relying on "if it blows up my 'phone then it's obviously violated the standard".Updated: the module which I've described above appears to have been unceremoniously pulled during the last month by all AliExpress sellers and replaced by one with a PCB marked v1.1, which carries an extra chip which is presumably the PD stuff for one of the USB-A ports.After this I'm doubly wary of all cheap multiport USB charger/PSUs, particularly if they make any claim to be "fast".MarkMLl

author: dav888
author_rank: Regular Contributor
timestamp: February 02, 2025, 11:59:39 am
content: also looking for a new one, but I really want greater precision on the current measurement...wishing there was one that works like the nordic PPK 2, basically several shunts with an autonomous switchover to pick the most relevant one for the actual current passing thru.big bonus if the analyzer also had a fast display / scope-view.