Power-Z KM003C Portable USB-C Fast Charging Tester PD3.1 QC5.0 Digital Voltmeter & Ammeter Power Bank Tester

ChargerLab KM003C is by far the most modern USB-C tester, preserving all cable lines, thus it is Alt DisplayPort compatible and allows for video signal transmission with PD 3.1 support. It is surprisingly small, and the screen displays more information than the competition. By far the best USB tester, kudos to ChargerLab.I am providing an overall comment for three USB testers, all of which deserve to be purchased as they complement each other perfectly and are consistent in their results.I would like to dedicate the majority of this review to the Bit Trade One model, which has recently arrived on Amazon. It deserves a shoutout because the tool is exceptional and inexpensive for what it offers.The ADUSBCIM is a USB cable tester that truly complements traditional USB cable testers. Only the cable to be tested needs to be plugged into the A and B ports, and the tool does the rest.The reference value for calculating the cable's resistance is taken using a CR2032 battery, and I note that the calculation is very precise and stable.You can find on Bit Trade One's ADUSBCIM GitHub page, in the Pull Request section, a manual in English in PDF format. This is my small contribution to the project, as the current official English manual is more of a word-by-word description that is difficult to understand.Thanks to this tester, I discovered, for example, that Anker cables, the 765 series, were actually poor high-resistance cables, and that I had much better options for charging. I ended up wasting money on cables that turned out to be slower than cables that were given to me for free with computer accessories.The FNIRSI FNB58 is a very comprehensive USB-A and USB-C port tester. It notably offers numerous rapid charging protocol tests, can test the quality and resistance of a cable, and obtain oscilloscope-like graphical representations. Now that we are on PD3.0 and with PD3.1 approaching quickly, owning one of these tools is now essential to validate the proper functioning of an installation.I've read a lot of advice on Reddit, and if you're looking to equip yourself with the best products offering the most testing possibilities, here are the tester references to get:- Bit Trade One ADUSBCIM (very thorough cable tester testing all the lines of a cable)- FNIRSI FNB58 (the most comprehensive, many ports, many scenarios, USBA/C Micro)- ChargerLab KM003C (the most modern, TB4, 250W)If you have these three or at least a combination of the cable and usb tester, it will take you no more than a few days to become a USB expert. 👌

I could not figure out why some of my devices were not charging as fast as they 'should'. I used this wonderful device to troubleshoot, and found that some of my cables were not great.This device is *fantastic* for troubleshooting and verifying you are getting what you think you are.For example I learned our car is only spitting out 7 watts from its onboard USB ports. My anker powerbank is a 140W unit, but I can only get 30W to my portable device. That's when I learned my portable gaming device has a charge limit of 30W - good to know, now I can plan for how long it will take to recharge under the best of circumstances.So much good use for this tool, I highly recommend! It comes in a nice metal tin case with a protective foam cutout surround to protect it.

This is the device to buy, if you want to find out just how much voltage and current your power supply delivers. It's worth the money.

Works great. This is the second one I’m buying, it does it’s job well.The only reason I’m buying a second one, is I lost the first. It's a "prosumer" level tester. It will handle 20x a week (my level). I think a 100x a week would be fine. If you have a few techs doing that usage, I'd buy it. Even if one fails after a few months, it's only $100. Most of the units will last longer. It fits in a pocket, so it's great for running around all over the place.It's not an industrial level device. I wouldn't recommend it for that. Anything that big wouldn't be portable.

A few things could be better starting with the $109 price tag. I was expecting a larger screen but it is great very good brightness/clarity. Another issue is when plugging into certain PD chargers it will not display, once a device is plugged in good to go this only becomes a problem if you want to check charge protocols and are potentially putting 20v+ into a device not designed for it (I believe it is not supplying whatever marker is required to turn on PD output?) For around $60-$70 you will get something that I feel is a little better downside is a smaller screen, all the features of this item, still USB-C - USB-C, works with every PD Charger I have without issue (23)