Hi,
I am working on a solar monitor. I will use Arduino/esp8266 and INAXXX shunt current (optional with voltage and power) monitors from Texas instruments.
My problem is the solar charger controller.
It has 6 inputs/outputs. Three pairs of negative and positive wires from solar panel, battery and output to loads
The solar charger controller has the three positive ones joined, so it works with positive common rail.
So I can't join negative ones as I would expect by using 3 INAXXX monitors and Arduino, as all these chips need to be joined by ground
Arduuno can measure negative voltages with resistor divider, no problem here, and also some shunt current monitor support little negative shunt voltage.
The problem here is how could I power my Arduino and other ICs.
Options:
1. Another power supply with output ground joined with positive rail of the solar charger controller. I don't like it, as I need another power supply not only batteries of the solar system.
2. Use a isolated dc-dc converter, input pins will be the battery (aprox 13 VDC), and join her output ground with positive rail. Arduino will see 3.3v or 5v (depends on converter). Here, the problem is that dc-dc converters can use almost 30 or 40mA with no load (for example, while I sleep Arduino), and my solar system is "little"
3. Here is where I ask you for help?
Is there any other option?
Thanks a lot.
I am working on a solar monitor. I will use Arduino/esp8266 and INAXXX shunt current (optional with voltage and power) monitors from Texas instruments.
My problem is the solar charger controller.
It has 6 inputs/outputs. Three pairs of negative and positive wires from solar panel, battery and output to loads
The solar charger controller has the three positive ones joined, so it works with positive common rail.
So I can't join negative ones as I would expect by using 3 INAXXX monitors and Arduino, as all these chips need to be joined by ground
Arduuno can measure negative voltages with resistor divider, no problem here, and also some shunt current monitor support little negative shunt voltage.
The problem here is how could I power my Arduino and other ICs.
Options:
1. Another power supply with output ground joined with positive rail of the solar charger controller. I don't like it, as I need another power supply not only batteries of the solar system.
2. Use a isolated dc-dc converter, input pins will be the battery (aprox 13 VDC), and join her output ground with positive rail. Arduino will see 3.3v or 5v (depends on converter). Here, the problem is that dc-dc converters can use almost 30 or 40mA with no load (for example, while I sleep Arduino), and my solar system is "little"
3. Here is where I ask you for help?
Is there any other option?
Thanks a lot.