Deegoo-FPV AT34 USB 3.0 r Power Meter 30V 4A USB Voltage Digital Multimeter Current r Voltmeter Ammeter IPS Color Display Capacity Power

It definitely needs a heat sink and larger enclosure. Values are approximate as they aren't static.Charging a phone > 3.6 watts, 5.14v, 122mwh. LED light >1.9 watts, 5.19v 158mwh. No problems.The LED has a heat sink and runs hot to the touch. The tester shuts after about 5 seconds.

Would like a larger watts display as that is a more accurate measure of charging power (volts x amps = watts). Good enough to test a few USB charges a throw out the old 5 watt chargers as no longer useful.

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.

Nice display that is very easy to read. It works well, does what I wanted and I'm happy.Testing USB devices, USB power supplies, Powerbanks, and USB ports was easy and accurate.

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.