Welcome to a new voltlog, the first one in 2019 and what better way to start the year than with a InTheMail video the series that will touch both your passion for electronics and your bank account at the same time. As some of you might know I’ve recently created my patreon page so for those that would like to support me making these videos, you will find a link the description below, any pledge amount is appreciated, even 1$, just imagine half of my subscribers pledging 1$ a month. And if you can’t offer any donations, that’s fine too, my content will continue to be free.
Links for all of the items shown in the video will be in the video description, on youtube.
Do I recommend getting this module? Yes, the accuracy is good, the resolution is nice 10mV 1mA and you also have the option for adjusting it manually for both voltage and current.
The design is pretty simple, I believe the microcontroller is an STM8S so hacking it and rewriting the firmware should be pretty easy but it already does what it’s supposed to do so I don’t see a point to hacking this module. I think you would be better off designing a panel meter from scratch.
Someone asked on youtube how should a panel like this be wired up, so here is a wiring diagram that you can use. In this wiring diagram our goal is to monitor the voltage and current for charging a battery.
Example 1 shows the panel meter connected before the battery charging module, which means it will measure everything, even the power losses in the battery charging module.
Example 2 shows the panel meter connected after the battery charging module, which means it will only measure current flowing into the battery or whatever load you have on the output.
In both cases voltage sensing is done right at the output but that wire can be moved according to your needs. Also in both cases the panel meter gets power directly from the power supply because at that point the voltage is constant.
The main thing to remember here is that these panel meters are designed for low side current sensing, that means the ground of the logic board of the meter is connected with the input of the shunt resistor.
Last InTheMail video was published almost two months ago so I think you will appreciate this one where I got some interesting stuff from the usual Chinese sources.
Links for all the items shown in this video below:
So I discovered this module a few months ago and it’s been sitting in a box since then, I almost forgot about it, until a few days ago when I decided it will be a good idea to do a video on the subject.
Let me give you a few details on the specs of this module and as usual it’s pretty difficult to find the information as it’s the case with every new module coming out of China. First of all we have an input range of 0-60V and 0-10A and a 5V rail is needed to power the module itself. It has a voltage measuring accuracy of ±0.2% + 0.2% full scale which sounds strange because these figures are usually given in a percentage plus or minus a number of least significant digits. The current measuring accuracy is ±0.4% + 0.3% full scale.
The meter is basically capable of measuring with a resolution of 1mv and 1mA (however the accuracy is quite bad, as shown in the video) which is quite nice and useful (not really useful with bad accuracy) for projects like DIY power supplies or DIY electronic loads. It can also display the power in watts with a resolution of 1mW as well as showing the load impedance.
In this episode I am building an analog adjustable dc load with parts easily obtainable from ebay and banggood. The advantage of such a dc load is that you can understand how it works, modify or repair it if necessary far easier than you would with a digital one. I was able to push mine up to 60W dissipation, but it is recommend to stay under 50W to protect the mosfet.
Here is a list with links to the parts used in this project:
