This is a sad story about how a terrible user interface can negate all the technical advantages of a device.
I bought an FNIRSI DC-5005L adjustable buck voltage converter for $ 14.68 (now it costs $ 18.56).
The technical parameters are excellent:
Input voltage: 8-55V;
Output voltage: 1.8-50V;
Output current: up to 5A;
Input reverse polarity protection, output short circuit protection;
Setting the output voltage with an accuracy of 0.01V and limiting the output current with an accuracy of 0.001A;
Indication of input and output voltage (2 digits after the decimal point), output current (3 digits after comma), power and operating time, displaying the consumption graph, displaying ampere-hours and watt hours;
Screen flip by 90, 180, 270 degrees, load disconnection timer, automatic load disconnection when the set protection current is exceeded, overheating shutdown.
In general, the parameters are cool. In terms of execution, everything is also on top.
And now back to the sad. For control, an encoder with a push and an output enable button is used, which at the same time turns on / off the consumption graph mode when pressed for a long time.
The encoder is inconvenient - it has a small resolution of 10 steps per revolution (for a good 30 steps) and a very tight pressure, leading to the fact that at the moment of pressing the set value is often lost due to the fact that the encoder is slightly scrolls.
What do you think happens when the encoder is rotated? Maybe you think that the output voltage is changing, which would be logical? NO! Rotating the encoder switches five screens (three display screens and two menu screens).
Maybe pressing the encoder turns on the output voltage setting? NO! On three display screens, it does nothing.
In order to change the output voltage, on the first display screen, press the encoder and hold it for 2 seconds. The tiny numbers at the top of the screen will turn white.
Rotation of the encoder will start to change the output voltage in 0.01V steps.
To change the step, you need to click on the enocder. After the first press, the same low-order digit changes (it is not clear why), after the second press the tenths, after the third unit, after the fourth tens.
After setting the voltage, press the encoder again and hold it for 2 seconds. Do you think that's all? Nope! The current will light up in white, which can be changed in the same way. And to exit the voltage and current setting, you need to press and hold the encoder for two seconds for the third time.
For example, here's what you need to do to change the output voltage from 2.5 to 10 volts:
1. Check that the first display screen is displayed. If not, turn the encoder to the left;
2. Press the encoder and hold it for two seconds;
3. Press the encoder twice to move to the tenth place;
4. Rotate the encoder half a turn to set tenths to zero;
5. Press Ecoder to switch to units;
6. Turn the encoder to set 10 volts;
7. Press the encoder and hold it for two seconds. There will be a transition to setting the current;
8. Press the encoder and hold it for two seconds.
And so for any change in output voltage.
For example, to do the same with a really handy Gophert laboratory power supply (https://ammo1.livejournal.com/1193982.html) it is enough to do the following:
1. Press the encoder twice to go to tenths of a volt;
2. Turn the encoder two and a half turns.
And it takes five seconds, not half a minute.
The FNIRSI DC-5005L step-down voltage converter can be used if frequent voltage and current changes are not required, but using it as a laboratory power source, this is hell (in which, by the way, there should be a separate, especially inconvenient boiler for the creators of such interfaces).
© 2020, Alexey Nadezhin
For ten years I have been writing every day about technology, discounts, places of interest and events. Read my blog on the site ammo1.ru, in LJ, Zen, Mirtesen.
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Lamptest.ru. I test LED lamps and help figure out which ones are good and which are not so good.
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