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17 of 18 people found the following review helpful.
Functions as described.
By My Penname
This review is for the DROK Micro Load Tester Board Electronic Load Equipment Module Voltage Charging Current Monitoring Tool Aging Device Discharge Resistance with 2A/1A Switch USB Port.
This item is a load tester used to put load on you USB power supply. With this load in place you can determine if your supply puts out it's correct voltage and amperage under load using an inline USB meter. One such inline USB meter would be the DROK Dual USB 2.0 Digital Multimeter Ampere Voltage Capacity Power Meter 7 Modes Monitor for Fast Charging Data Sync DC 3.2-15V 0-3A Volt Amp Charger Detector Mobile Solar Panel Alignment Tester (ASIN B00J3JSEG6).
First the physical package.
The unit is not marked for manufacturer, UL or CE. The unit is 3 in long (USB plug included), just over 5/8 in wide, and just under 1/2 in thick. When plugged in it sticks out 2-1/2 in.
On the unit I received there were small chips in the resistor coating and a mild scratch in the PCB coating on the rear side. Neither was big enough to make me worry but it is worth mentioning as new items should not be scratched and chipped.
Also, on the unit I received the switch was soldered with a gap to the board (large enough to get my fingernail into) and slightly crooked. This is only an ascetic issue and doesn't affect function. The soldering quality seems alright and they did sand the leads to remove any obnoxious sharp points. The edges of the PCB were also blunted as not to be sharp.
On to function...
The USB plug fit in the socket snugly but not overly tight.
When plugged in my meter read .92A on the 1A setting and 1.72A on the 2A setting. To me .92A @ 1A is fine but 1.72A @ 2A is a little light. It's not too far off and perhaps it's my power supply or meter so I'll let it slide.
The LED is bi-color and water clear. It glows green on the 1A setting and red on 2A setting. Being water clear it glows obnoxiously bright on green and is tolerable on red. The green is bright enough to leave “shadow spots” in my eyes even after the shortest passing glance. I will probably rub fine sandpaper on the top of the LED to make it opaque.
The resistors do get hot under load so be careful. There was a slight smell the first time I ran it but it went away within a few minutes.
Overall the unit functions as intended and was a good buy.
So why four stars then?
-1 star because the build quality is lacking.
The switch is soldered on crooked, there are small chips in the resistor coatings, and a little scratch on the PCB coating. While none of these directly affect function they show a lack of quality in general. Also, the LED is water clear and way too bright on green. This is an engineering issue and a moderate brightness opaque LED would work better as an indicator.
All this said, the unit functions as intended so it was a good buy at the six dollars I paid for it.
10 of 11 people found the following review helpful.
Ok under 1Amp load, but not up to spec under the 2Amp load,
By Gadget Review Videos
Even though I've recommended this device from DROK in another review of mine I may have done so a little to soon. The one I received has a different PCB and switch from what is show on in the picture, normally this wouldn't be an issue unless it effect performance. In my case it does effect performance. Using a single resistor for a 1A load it come out to be 0.98A, that's close enough. But when I flip the switch for a 2A load I only get 1.82A. Now if the first resistor is the same quality as the second one I would have expected 1.96A as the load. So I suspect this is either the added resistance from the cheaper switch that came on mine, or the change in the PCB, or the second resistor isn't doing 1A, or maybe even a cold soldering joint. But I have not had the time to inspect it to find out why it's considerably less when I switch it over to 2A.
I can say I've tested this with my multimeter inline using my desk variable power supply with good gauge wire to rule out the USB power supply as the issue, and my desk power supply will provide up to 5.1A, or even 10.2A when in parallel mode so I know it had plenty of power to pull from.
I stopped after that test, I shouldn't have to waist my time testing and trying to figure out why something I purchased to simulate a 2A load is only pulling 1.8A. But I suspect it may be the cheaper switch I received on my unit?
For most people it mays draw enough power to test your wall USB power supply or test your cables performance. I guess I'm not most people and I do a little more and needed something to simulate a full 2Amps current load.
UPDATE: I decided to look into why I was seeing a different reading in the 2A load. It ended up being cold soldering joints, and through hole component that were not solder though and not making good contact with the PCB pads.
Basically, I ref lowed the board one joint at a time. So in the end I'm getting 0.98A on the 1Amp load, this is acceptable with the resistance of the power meter I'm using to measure. If I use my fluke in line I get 0.99235. I also replaced the switch with one that had better current contact and removed the LED since it just takes away from the lower and isn't really needed.
But after fixing the so,dear joints I know get 1.95A instead of 0.82. So I raised it to 4 stars only because I had to fix the shotty soldering joints myself and spend time on it. If you have lab equivalent testing equipment and see the same thing I would just exchange it. But on the other hand if you have this equipment you will most likely just fix it yourself.
12 of 13 people found the following review helpful. See all 84 customer reviews...
current and power a USB port delivers but that just got more useful. With old-school wirewound resistors as dummy loads for ...
By Martin Winston
We've known forever that USB chargers sometimes fib about their ratings. We have gear to measure the Voltage, current and power a USB port delivers but that just got more useful. With old-school wirewound resistors as dummy loads for just short of 1A (5W) and just short of 2A (10W) we can see if a port under load looks every bit as healthy as it might appear to be "naked". THis dummy load is a product we sought out - one that solves a problem, simply and well - one we might have tried building ourselves if we hadn't found it. If you're smart enough to double check USB power sources and smart enough to have inline metering to help with that, a good 2-setting dummy load brings those measurements into the real world. Those resistors do get hot (expected) so be aware of that when you unplug. For your testing, this is the piece that Ohm's Law says you should have.