Hello, friends. Today I want to review a pretty useful device. RD LD25 USB tester with built-in load.
Using this tester, you can quickly determine the quality of the charger or other power source via USB. It turns out the device is 2 in 1. A kind of mini-combine.
This electronic load has the following characteristics:
Comes to the buyer in a foam box. The fact that during delivery the device may suffer can not worry. The load looks like some kind of tricky flash drive with a radiator and a fan:
At the end of the load there is a small display, two buttons and a twist knob:
There are also two buttons for selecting the mode and turning on / off the load:
On the other hand, there are MicroUSB, Type-C and regular USB ports:
Below is the electronic load board itself:
The general assembly of the load is of high quality. But the impression remains that there is not enough housing. The device looks a bit unfinished. Although on the other hand, the load costs less than $ 10. And this means that the manufacturer simply saved on the case. Those whose hands grow where necessary, can themselves make this body. Or they may not. For me, even without a case, this load works fine.
In order to see the burden in the work, naturally you need to apply power to any of the three inputs. I connect to the usb port of the phone's charger. The screen lights up. The red numbers in real life are clearer than in the pictures, but in general there is clearly not enough of any kind of light filter. The display shows amps, volts and power:
V and A is understandable. Power is displayed by the letter P:
There is no built-in trigger in the load. But if you use the external one, the load will display the current voltage without problems:
Well, actually for what the load can come in handy. To check the chargers. USB cords and power banks.
For example, I have this not very powerful block lying around:
On the case of this charger it is indicated that it is capable of delivering up to 1.5A:
I connect the load, turn it on, watch:
At 1.7A, more or less normal:
But if you give 2.1A, then the voltage drops very much. Up to 3.4V:
But then no one promised us anything. Within the claimed charge is held. And considering that it costs less than a dollar, and that’s already good.
But here I have another charge. It costs 2 dollars. Remaks SR-9288. And it says on it that she can give up to 2.1A:
I connect the load to it, I set it using the 2.1A twist as stated:
And what do I see? Voltage dipped to 3.4V:
And this means that the manufacturer is brazenly lying to customers. Charging trash. More than 1A, she is not able to give:
And to find out, you just need a monitored device.
Such a load can help check all the chargers available in the house, as well as be a useful tool, for example, if you are going to buy a charger offline. Well, or got a charge with aliexpress, we checked it right away and found out if it corresponded to what the seller said or not. if it does not meet, boldly open a dispute, and get a refund. Of course, I do not call for collecting charges in this way, simultaneously punishing sellers. But everything happens.
For $ 9.99, this is a pretty good purchase. Checks power supplies. Shows what they are capable of, if necessary, you can conduct a stress test. In the home, it can be very useful.
For those who are interested in this load, now there is just a discount. Can be bought at the selling price:
RD LD25 Electronic Load resistor USB Interface
For example, I have a whole fleet of similar loads and testers:
But sometimes I need to check different chargers for work. So there is so much. And for normal use, the observed load will do.
For those who are interested, the following testers and loads are in the photo:
one. Mantistek usb doctor
All these 6 testers and loads are constantly in my work, and often help. Therefore, I can also safely recommend them for purchase.