arduino Image


Automatically switch on Phoenix 12/500 VE.Direct on recharged battery


is there a way to turn on the Phoenix 12/500 inverter at a defined battery level (or voltage)?

I have a small island system with 240 Wp charging a 55 Ah/12V LiFePo via SmartSolar MPPT 75/12. This is running fine so far, but I often have a fully charged battery with no way to discharge it on the 12 V system (which I use to charge smart devices and notebook computers). So a lot of sun energy is wasted (charger in float mode).

So I installed a Phoenix 12/500 inverter that now runs a fridge most of the time. I also installed an automatic transfer switch, so the fridge gets landline power in case the battery is too low for the inverter. This also works fine.

But now the inverter discharges the battery completely and then it does not turn on again, when the battery is full again. But I would like to switch off at 20% battery level (so I have enough spare for my more efficient 12V system) and automatically turn on at 80% battery level (so the inverter just kicks in, when I risk to run into a 100% full battery)

Is this all possible with the two Victron devices or will I need to read the battery level with an Arduino via from either MPPT or inverter and then switch the inverter manually on and off via the remote control port of the Phoenix?

Thank you very much


oli-1 asked
ripper answered ·

1 Answer

MPPT75/15, use of 5V of Victron port as 5V power supply ?

Hello team!

I have a SmartSolar MPPT75/15 and i'm asking if 5V of the Victron port could be use to run tiny MCU like Arduino or ESP8266 ? What is the power capability of this pin ?

I know I can use a regulated voltage and current from LOAD output with more components...

Thank you


biozor asked
biozor answered ·

3 Answers

18 Posts
16 Users

Topic Experts

0 Points