AT34 USB 3.0 Tester,USB Power Meter 30V 4A USB Voltage Tester Multimeter Digital Multimeter Current Tester Voltmeter Ammeter IPS Color Display Capacity Power USB Charger Tester

Glad i bought this. I found 2 adapter that was an out rite lie rated at 2 amp only doing 1 amp or less straight to the garbage they went.In short if you have an adapter that is taking a long time to charge something test it with this to see the output when the battery is dead many companies will over rate an item 2 amp you can expect 1.7 amp or better and watch the voltage sag if it less than 4.5 volts at full load toss it in the garbage. i had one rated at 2 amp and it was 3.97 volts @ 1.1 amp total garbage. The other barely 1 amp @ 4.9 volts garbage it went. Folks with todays tech stuff you need at least 2 amp and a stable voltage to get the phones and tablets charged in a timely manner and have enough reserve power to still use the devise.The battery in the devises is 4.2 volts and charging 5 volts in gets regulated at 4.2 if there is a bad voltage sag it takes even longer to charge. Im getting one 2.4 amp amazon basics adapter to see how it works to replace the 2 that i tossed out. If it does what its suppose to i may buy another one if not ill send it back but ill post a review on it as well.

I would have loved to have given this 5 stars because it's really accurate and it provides all the information you would need on a USB port. The Display while Bright and clear has an issue with some of the values being so small that only younger people will be able to read them clearly. I had to really get up close to see some of the Values. Luckily the Most important stuff is easy to read.

I am working on very low power IoT devices and I wanted an easy way to get a ball park measurement for how much power was being used without hooking up an oscilloscope or other equipment. I compared the measured power consumption against the o-scope and got 9.39ma versus the 9ma shown by this unit. It is close enough for me to use it as way to judge whether code changes improve the deep sleep current drain.This is a great tool if you want to quickly check current draw by a USB device.

I have not had a lot of time to test and use this. I have used it a few times and it was dead on perfect in its reading. I have to figure that it will stay this way. It comes with the device in a nice small storage case. This case is a nice touch as it will keep dust and other foreign objects from getting in and on it.Operation is simple. (Once you find the buttons.) It is very bright and can be seen anywhere you use it. So far so good. If I experience any troubles i will update this review to reflect them. But I do not think that is going to happen.

I bought this for a specific purpose since it did say it was capable of 30 volts and 4 amps. So a 9 volt fast charger at around 2 amps should be read just fine correct? Well this tester is restricting the amount of power going to my devices and won't ALLOW anything to fast charge. For 5 volt stuff it kind of works. For instance at 5 volts and 1 amp this meter will work correctly. Bump up the amperage to 2 amps, still at 5 volts, and this so called meter won't allow that much power to pass through it.What I'm trying to say is that the meter itself is restricting the power flow to very slow charging speeds. I use my phone charger and its cable and it tells me I have whatever amount of time to fully charge my phone. Then hook it up to that same charger this time through the meter and the phone tells me to check my cables and charger because its charging so slow. Earlier, on the charger I had 56 minutes to full. Using the meter trying to read the values of the 5V 2A charger the time went up to 1 hour and 53 minutes. I cant check the fast chargers I have because the meter won't allow the charger to output in 9 volts.Wth did I get a bad meter? If this thing is supposed to be capable of 30 volts, 4 amps (120 watts) why then will it not even allow 5 volts 2 amps (10 watts)?Something is very amiss here....either crappy workmanship or flat out misrepresentation of what this item actually is or what it can do.Why is this allowed here? Judging from the device I was sent, compared with what its truly cabaple of versus what it's being advertised as, someone somewhere isnt telling the truth.I've literally spent hundreds upon hundreds of dollars here this past year. I would not be here complaining about a $12 part if it weren't about the principle of the issue and I flat out feel lied to and think the seller lied.Now I have to go through the trouble of packing it back up, taking it somewhere to ship it back where it came from, and wait and hope it gets where it's supposed to go and get my lil pocket change back.Its frustrating and annoying.This meter, which I was definitely looking forward to, turned out to be a huge pain and worthless for my purposes.I'm kinda sad now. Thanks.

I bought this item to see if my cables are carrying enough amperage, it lets me know which charging cables work better than others.It also showed me that when a charger could not deliver the full 5 volts that the amperage dropped. When this happens the PHONE is detecting the charger is not working correctly, so the PHONE chooses to demand less amperage therefore voltage going back to normal but charging is now slower.

I use this meter to test a variety of solar chargers and battery packs. It is very easy to use as it automatically starts measuring and the settings are adjusted with just one button. It is helpful being able to flip the display output depending on the angle of the device I am trying to measure. The one drawback to this meter is that it can be difficult to view in the sun (i.e. testing a solar charger). I've attached pictures showing the difference between outdoor and indoor views. Overall I think it is a quality meter and I use it regularly.

4-bit accuracy for more accurate measurements; Measure the load equivalent impedance and power; Thermometer function, Celsius and Fahrenheit free switching: Using high-precision thermistor sensor; USB 3.0 interface: Compatible with USB 2.0, support high current test, support USB3.0 interface mobile hard disk and U disk test.