Solar Panels/Battery monitor

Hi, I just wanted to share some of the results of my home automation project.

http://elrobot.top/SolarGuests.php

Moving to the Dominican Republic some 17 years ago I realized quickly that electricity was a luxury, So I installed over 2kw of solar panels.

Recently I wanted more control on the system as well as live data on my cell phone. There were may ways to do it but I settled of mysql database and some php files on an old laptop running linux.

Initially I was only updating the PHP file with no database… Because the project is now going to full automation of the house, a database was required.

For this part of the project I use an Arduino nano, a esp8266, an ads1115 ADC, a Real time clock module and a buck converter. Also on the original page (Not this guest page because of my low bandwidth) I have a live camera stream for the from gate at the house. (Nice when the door bell rings and want to know who it is...)

I designed a PCB in DipTrace and assembled it. (I will be making an other PCB because I also want the watts that the solar system is giving out… To come…).

If I can help anyone with what I learned here just let me know.

Cheers! Marc

Hi FlyDr2

Am interested in assembling a similar system. Please could you share documentation: components list, wiring diagrams and code.

Looking forward to learning from you.

im eventually going to get to a similar point in my project to include solar but for now i am working on the generator half og my project.. currently my android app runs on bluetooth however i havent gotten to the wifi of things. what did you use for your current sensor solution... my generator puts out 200A x 8 and sensoring this is a bit costly ...

tbillion: what did you use for your current sensor solution... my generator puts out 200A x 8 and sensoring this is a bit costly ...

The existing cables to/from the generator/battery can be used as shunt resistors. Try measuring the voltage (millivolts) across a length (30-60cm) of this battery cable with a DMM. A chip like the INA219 can convert that small voltage into a digital value. Assuming voltage on the shunt is within the common mode range of the INA219. The INA219 comes on breakout boards from Adafruit or ebay. Leo..

You might be interested in InfluxDB and Grafana to store and.plot collected data

@Wawa .. your saying use the cable itself as a shunt resistor... wouldnt corrosion make this a bad idea? becasue corrosion over time leads to increased voltage drop.

@musskopf i have a custom made android app for that..

tbillion: @Wawa .. your saying use the cable itself as a shunt resistor... wouldnt corrosion make this a bad idea? becasue corrosion over time leads to increased voltage drop.

Corrosion of what. The connectors? Could be wise to use Kelvin connections to the wire, like on a real shunt. Leo..

tbillion: im eventually going to get to a similar point in my project to include solar but for now i am working on the generator half og my project.. currently my android app runs on bluetooth however i havent gotten to the wifi of things. what did you use for your current sensor solution... my generator puts out 200A x 8 and sensoring this is a bit costly ...

That's exactly what i did... An ADS1115 reading voltage between the charge controller and the inverter... Then from the inverter to the battery bank using the wires as shunt.

Just weld a pin and stick it in the cable at both ends of the cable... read the voltage diff. (Use proper voltage dividers) Then use a multiplier to calibrate. Google "Using wire as DC shunt"

The longer the wire the more precise the readings are … More of a difference.

mugambi: Hi FlyDr2

Am interested in assembling a similar system. Please could you share documentation: components list, wiring diagrams and code.

Looking forward to learning from you.

Well I'm willing to help but if you have no idea where to start it can be complex.

I have no doc. all in my head.

Components are listed above.

Wiring diagram in my head. If you want my messy code PM me. I doubt it would be useful.

Start somewhere then ask for help on resolving issues.

musskopf: You might be interested in InfluxDB and Grafana to store and.plot collected data

All I wanted initially was to be able to switch from “Street Hydro” to “Inverter” But then the project evolved. I’m not looking at logging at all. Thanks for the suggestion.

Since my 1st post on this topic.

I’ve added email (from php) and push notification (using pushbox and newtifry) to notify me if:
1- The hydro went offline
2- The Hydro came back
3- Batteries at 50%
4- Batteries at 30% (Dead just before shutdown)