RuiDeng UM25 vs. UM24 USB Charger Doctor - 12v Solar Shed 

Great review. I think it might be good to note in the video description above that the device is in fact *more* accurate than the UM24, since the documentation switches from percent - % - to permille - the 0/00 symbol, which I can't seem to paste here.

Hi, Adam! Great review! Your video (rich in details) helped me a lot in the purchase decision. You have won another subscriber. Thank you so much!!!!

Good video as ever, been meaning to pick one of these up as they are always popping up as recommended items wherever i shop and look really handy. Shall make sure i get the new one :-)

brilliant video many thanks

glad your OCD is as good as mine (removing screen protectors before even starting) ;)

I learned something! This UM25 is really neat...I wouldn't mind using one for USB QC3.0 voltts/current/wattage monitoring.

Nice video, I have the UM25C, it serves me very well. I really like the bluetooth software, for low voltages I use it as a voltage meter on my PC screen. One mayor improvement Rui Deng could implement is faster measurements (like the Power-Z max. 10ms sampling rate).

Useful video

Say that name huweeey-wi. I love how you said it 😂

Is there something like this for 3.7v li-ion foil packs?

At what value should "stop current" be set?

Great review. I didn't know the graph can be manually scaled on the PC software. Its not in Ruideng's own docs. Great find.

Thanks for this! Is it worth to spend 50% more for the UM25 version? This is the price difference where I live.

I also have both but I am not too sure about the UM25C. The temperature reading on mine seems to be 2 to 3C higher than the UM24C. The UM24C is spot on as I measured with 2 other thermometers. Well not a biggie, but still a precision device... I've also had it twice now that I had to re-calibrate the UM25C since it showed like a couple of mA of consumption when no load was connected to the device.. also has never happened on the UM24C.

I just received a UM25 but have found that it doesn't switch on (i.e. the screen stays blank) when I plug in a USB-C Power Delivery power source. I'm not sure if I'm doing something wrong or if it's faulty.

The powrbank has one 1A port and one 2.1A port, probably has to do something with the data line voltage.

Nice vid! They look really handy, might get myself one! Do you know if they can graph out wattage? Cheers mate! :)

The UM25C pc software also works on the UM34C no need for touchy screen phones.

Спасибо

Shame the loads weren't swapped to see if there was an actual difference.

Adam Welch says OKZU is lovely then I will obtain one! Its price is reasonable and the new version delivers 5VDC 3A! (The one in this video is 2.1A, and older version) But I really do hope it deliver what it claims to deliver. Very many power banks are full of claims, even the famous ones. I think there are too many people selling the same thing (same famous names) that could be or are a fake.

I'm happy with the UM24 by now, if they fix the software for the UM25 I'll buy it immediately

What's the point of having ten times the resolution, if the accuracy is worse by a factor of 2.5 plus a wider error in the last digit? It's very tempting to assume that the claimed accuracies for both devices are specious. That ~20 mA discrepancy is a 4% difference, not 0.2% or even 0.5%. It looks as though there's some crafty marketing going on with those units, as with far too many imported goods. Thanks for the review, Adam

when will you be doing another video on the diy bms?

I reversed engineered the um24c communication protocol. Probably will not find time to put it up on github, but here is the packet structure in case anyone is interested. #pragma pack(push,1) struct UM24C { uint16_t start; uint16_t centiVolts; uint16_t milliAmps; uint32_t milliWatts; uint16_t cTemp; uint16_t fTemp; uint16_t group; struct { uint32_t mAH; uint32_t mWh; } groups[10]; uint16_t centiDplus; uint16_t centiDneg; uint16_t mode; uint32_t mAH; uint32_t mWh; uint16_t stopCurrent; uint32_t recTime; uint16_t recording; // milliAmps > stopCurrent uint16_t screenOff; uint16_t screenBright; uint16_t state; // milliAmps > 0 uint16_t deciOhms; uint16_t screenPage; uint16_t end; }; #pragma pack(pop)

The phone app works after installation, anyone figured out how to fire it up after closing it? The only way I can get it to work is to re-install it, then open. A bit of a bugger, these off piste apk's...

Next USB Display Tester and I hate them at all, because they are not very acurate. Best Tester you introduced is the Portapow, it has his own battery and is very, very acurate about I want to know.

Great to say „Volt“, instead of „volts“. The same should be for Lumen, instead of „lumens“ and Meter instead of „ meters“.

The UM24 THAT I BOUGHT ABOUT 6 YEARS AGO FROM WISH BOTH HAVE BLUETOOTH SO YOU ARE WRONG! WHAT ELSE ARE YOU WRONG ABOUT? So you are guessing about what you are looking at?

dang huie! I never even tried to pro bounce that name! I hate usob cables! they are nice and convenient. I just have trouble with them when they are used a lot. the one on my phone is crappy. and the one on a tablet I had FELL IN! and one in a wall adapter had to be fished out and fixed. I wouldn't mind them in something that's constantly used. I use my phone a lot while charging! that don't help.

No point having extra decimal places if in fact its less accurate surely?

Tt

it's pronounced... Waa Wee

If its "ho a wee" then maybe they should print that in English.