diy solar

diy solar

Off-grid Solar / Battery monitoring and control freeware

Why not just use a Debian-based Linux distro on a full-fledged computer instead.

Because most people just want to have a small headless system to monitor their installation instead of a full blown PC/laptop with screen etc - not to mention that a Pi will use a fraction of the power needed, and that matters for a lot of off-grid people.
 
My laptop uses 10W. The external monitor uses some 30, but even with a Pi, you would need a screen.
And most people have - and use - a PC anyway. My laptop, really powerful and fast, I bought used for 200€. A Pi will set you back for some 100. Plus extras, and the monitor. Waste of resources :·)
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Headless. You set it up, do everything over SSH over the network. Nothing needed.

You'd need a monitor (or at least a laptop screen) to do that though - and to see the graphs - so...
OK, most people don't want to use Linux. I can understand, you need to learn it. But in that case, why not just write the stuff for Windows?
A Pi uses Linux anyway. Waste of resources ·)

Which one is that??

Dell latitude e7440. 10W, with the screen off. Measured with Kill-a-watt.

I'll try again with - job_name: 'node'. :·/
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You'd need a monitor (or at least a laptop screen) to do that though - and to see the graphs - so...
OK, most people don't want to use Linux. I can understand, you need to learn it. But in that case, why not just write the stuff for Windows?
A Pi uses Linux anyway. Waste of resources ·)

Grafana and other tools are intended for server usage, and the majority of servers run Linux.
You can check the graphs etc. remotely from a phone for example. In my case, the Pi just sits there to log the data (no screen, no keyboard, nothing but the Pi), the actual display is remote from anywhere I want, be it my phone or a laptop or whatever I have handy wherever I am.

The Pi consumes < 5W.
 
++ on the headless Raspberry Pi

I would add that the Pi power is powered by USB (micro or C) so it can run off DC with the proper common adapter. I don't have to run my power hog inverter in my RV for the Pi to have power when I'm off-grid.
 
My install is in an RV. The Pi4 runs off a 12-5v converter. Using a desktop/laptop in my application is a waste of space & power. I also have Plex on the Pi4 so it's my media server as well. The choice of what hardware to use is specific to each person. The cost of the Pi is a tiny expense in the total system cost so that's not a factor.

I can view the Grafana panels from my phone, laptop or Pi Touchscreen display (on a Pi3)
 
Before you get any custom solar stats working in Grafana, you need to get the base system working, use one of the system monitoring add ons that show cpu usage, load, network activity etc. Then you know the core Grafana/Prometheus system is working.

This is very well documented and the single most popular use of Grafana.

Only then add your custom solar info.
 
Trying to understand what cable I need to connect the Renogy wanderer 10amp to the pi? Can't seems to find the correct connection!
 
You need a genuine RS232 cable, beware of cheap copies that don't work. I have posted the pinout a few times in this forum with photos. Connect pins 2, 3 & 5 with solder or use a breakout. You need an RJ11 with 6 pins for the Renogy connection.
Good luck!
 

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You need a genuine RS232 cable, beware of cheap copies that don't work. I have posted the pinout a few times in this forum with photos. Connect pins 2, 3 & 5 with solder or use a breakout. You need an RJ11 with 6 pins for the Renogy connection.
Good luck!
Thanks a bunch! Will be trying this. Anything you found that would be a more "elegant" connection? For example would a rj11 to USB connection work? Such as this:
 
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I showed you my test rig as that shows the layout. You can use a DB15 breakout connector to make it look good, or cut the cable and directly solder the 3 wires.
Unfortunately, this is not a commodity cable you can buy, you have to make it yourself, but it's been very stable.
 
I showed you my test rig as that shows the layout. You can use a DB15 breakout connector to make it look good, or cut the cable and directly solder the 3 wires.
Unfortunately, this is not a commodity cable you can buy, you have to make it yourself, but it's been very stable.
I'm seeing only RJ12 6pin rather than RJ11 - this correct?
 
On my Rover I'm using a RJ-USB cable that came with it. On the Tracer I used prior I ground down an ethernet cable connector to fit into the 6 pin socket and modified an RS-USB cable to work.
 
On my Rover I'm using a RJ-USB cable that came with it. On the Tracer I used prior I ground down an ethernet cable connector to fit into the 6 pin socket and modified an RS-USB cable to work.
Any pics or explanation on how you modified the USB cable with this?
 
Any pics or explanation on how you modified the USB cable with this?
I'm on the road until April and the cable is at home. It was similar to what BarkingSpider did though. Make sure you get a USB cable that has a genuine chip in it for the data conversion as some of the knockoffs don't work
 
What could be causing an error. "Failed to read from instrument"?
I got this to work, but needed to reformat the sd card. Using the same hardware but this error keeps showing up.
Using the Renogy Wanderer.
Any debugging ideas - Kind of banging my head on the wall here.

Here is the full output:
Reading Renogy Wanderer data...
MinimalModbus debug mode. Will write to instrument (expecting 7 bytes back): 01 03 00 0A 00 01 A4 08 (8 bytes)
MinimalModbus debug mode. Clearing serial buffers for port /dev/ttyUSB0
MinimalModbus debug mode. No sleep required before write. Time since previous read: 10016.35 ms, minimum silent period: 4.01 ms.
MinimalModbus debug mode. Response from instrument: (0 bytes), roundtrip time: 2.0 ms. Timeout for reading: 0.0 ms.

Failed to read from instrument
 
There's no working connection to the Renogy. None of the debug statements indicate any comms success as far as I see it.
 
Is there is list of compatible hardware and hardware that is expected to work but needs testing?

I would like to use this, and would be happy to build a version to use with my setup of 48V 100AH LiFePower4 Battery by EG4, JK48V100 100 AH LiFePO4 Jakiper Battery, and 3.5 kW MidNite Solar MN3548DIY. Which, if any, of these three should work?

Thanks.
 
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