Gain/offset adjustment/configuration for the Homey Figaro Smart Implant app?

[nosern 0]

I have a Homey Pro system with several Figaro Smart Implants. Very flexible and great devices! One of these implants are logging the voltage of a solar cell equipment, AN1 to the solar cell and AN2 to the battery charger output. The voltage output is in the range 12V to 18V so I have a used a resistor divider to get a voltage between 6 and 9 voltage as input to my Homey Pro system. The analog inputs are configured without the internal pull-up resistor. Is there any way that I can configure the Figaro app configuration to add a gain of 2 to these voltages to display the correct value in my Homey Pro system?  It seems that I can only configure the change of voltage and time for updating the value, but no offset/gain adjustment of the voltage values?  I assume that this will always be an issue when converting a voltage signal to the 0-10V range for the implant.

[Martin_N 154]

@nosern

I don't know the programming options of "Homey Pro".
However, if you are asking about the possibilities of analog input 0-10V, then with Fibaro, for example HC3, there is the possibility to assign appropriate values to these limits. HC3 then recalculates the voltage between those limits in the sense of 0-100% = 0-10V, or in transparent mode a really direct measurement of the 0-10V voltage at the input (with a step of 0.1V).
If your system can assign an offset for the obtained values, it will only be a matter of your system's capabilities and possibly some programming.
If you want to measure the voltage outside the specified range, the right way is a voltmeter with an output of 0-10V, where the input values will be converted into the range for you, which can then be entered in the system.

And, yes, if I was going to measure the voltage directly, as in your case with a voltage divider and display the status in my HC3, there is an option to create a QuickApp and create the given offset within it.

[nosern 0]

Thanks Martin_N! If I understand your answer correctly there is no option for zero/gain adjustment for the Figaro Smart Implants and I need to deal with that in my system.

[GanzConrad 7]

hope You will find something usefull in my post:

Please login or register to see this link.

there is solution, how to convert lead acid battery voltage to 0-10 voltage

i didn't test it...

[Martin_N 154]

@GanzConrad

@nosern

 

GanzConrad> Yes, your post is interesting and can certainly be useful to someone who is not afraid of a little DIY :).
Well, it doesn't really matter if you use a zener reference, a voltage divider, an operational amplifier... You will be comparing to some reference and you will usually have some drop voltage and you have to perform conversions again.
The interviewer wanted to correct the measured value (from the voltage divider) with some offset for direct voltage measurement. I don't know Homey's capabilities, or his programming skills. Smart Implant can measure in the range of 0-10V, transmit this value and it is up to Homey's abilities to interpret this value.Going back to the zener reference, TI really has an interesting chip at a "few cents" price. TL431.
I did some simulation with it where I tweaked the resistor values. The graph shows the dependence of the input and output voltage in the range 0-19V (at the output 0-10V).

 

 

Please login or register to see this spoiler.

 

 

But,.. again it's just adjusting the measured value to the range, not a direct voltage measurement.
If it can define this range in Homey, it will then get a net value in voltage.

 

eM.

 

 

Edit: DYI to DIY 🤫

Edited March 15, 2023 by Martin_N