Where to start, SMA2500u,WMV700s, rPi, x86 10" tablet, etc

Hi, I’ve been poking around here for awhile on @stephen thread(WVC inverter MQTT Data logging for all versions of inverters) with a single WVC inverter and a panel, but recently things changed. I’ve added a number of panels and a few more WVC700 inverters, my ESP8266 running esp-link died so my JAVA code pulling data the SMA2500u needs remaking. It sure seems like OpenEnergyMonitor is the glue I should be using and instead of pushing out XML from the SMA2500u setup I should do something like put an Arduino on it with an HC-12 and make it look like another system/inverter to Stephens script or publish MQTT as wvc does.

Kinda undecided in how this might work and while I’m at it, my HVAC thermostat is really dumb with just on/off times 7 days a week and I had to hack an Arduino on the fan line to have a fan-only timer. So my HVAC thermostat needs an update too.

So with what looks like 3 MQTT devices( 2 publish-only and 1 pub/sub ) what do I do with OpenEnergyMonitor. I have some rPi’s(3B+, 4B and ZW) but I also have some of the Hackaday 10" x86 tablets( Blog | Hackaday | Fresh Hacks Every Day ) which might make for a nice UI/Terminal where the thermostat currently is in the center of the house. The SMA2500u RS232 port is out in the garage where WiFi is weak so another reason for 433MHz HC-12 setup spitting out messages to Stephen’s wvc script. But the 10" tablets don’t have much GPIO but does have a USB3.x port and a USB2/OTG port which I figure would be best to use one for flash memory when power goes out(no batteries on these ~$3 tablets).

So what would you guys do with:

  1. SMA2500u RS232 cable in the back of the house.
  2. Some WVC700 inverters spewing 433MHz data(collectable with wvc which spits out MQTT to OpenEnergyMonitor)
  3. Dumb thermostat in the center of the house making rooms too hot in the AM when it shifts from 60F night setting to 70F morning.
  4. some rPi’s, some x86 10" tablets(no batteries), some HC-12 modules, esp8266, esp32, some Arduinos and a bunch of history using Linux.

if you want my wvc script is based on openwrt, collectd, influxdb and , mqtt
you can use rPI or even orangpizero or hundred of compatible IOT devces out there - I run everything off a single opensource router - banana pi R1

basically for mine install openwrt on your device - install collectd, collectd-mod-mqtt, collectd-mod-network, mosquitto-ssl, and nano ( what ever else you may want ( i would not install luci-statistics as it would then over write collectd.conf and you have modify luci- statistic interface for that - you can find my howtos on openwrt forum for that an luci- collectd-mqtt interface )

then in nano /etc/collectd.conf add this

aseDir "/var/run/collectd"
Include "/etc/collectd/conf.d"
PIDFile "/var/run/collectd.pid"
PluginDir "/usr/lib/collectd"
TypesDB "/usr/share/collectd/types.db"
Interval 30
ReadThreads 2


LoadPlugin mqtt
<Plugin mqtt>
        <Subscribe "Subscription1" >
        host "127.0.0.1"
        port "1883"
        topic "incoming/#"
        </Subscribe>
</Plugin>


LoadPlugin network
<Plugin network>
        Server "localhost" "25826"
        Forward false
</Plugin>

then install influxdb , chronograf and Kapacitor that is suitable for your device architecture - configure influxdb for collectd inputs

now if it is configure properly all published data point will automatically go to influxbd and you build your visuals using chrongraph

for your thermostat you can install domoticz for home automation
for your screens you can look at my RA8875 sketch which just subs to my mqtt post and draw live graph of the published data points

1 Like

Interesting, I’d thought it fed into OpenEnergyMonitor but now that you mention it, I do recall seeing OpenWRT mentioned in the wvc script. I’ve messed with Grafana and infuxdb so Chronograf sounds interesting and while I have a couple of OpenWRT routers around I think I might make this work on one of those x86 tablets first.

And I need to fix up an Arduino with an RS232 serial I/F and HC-12 to get data from my SMA2500u into the wvc script.

More interesting stuff as I was not away of Domoticz and currently all my smart lights and switches are just tied to Alexa via Tasmota firmware upgrades.

Thanks for all the feedback!

your welcome – for me i like to squeeze as much as I can into a single low power device . I like the bananapiR1 or R2 open router platforms … for me it does all my home automation, network monitoring and routing, zigbee hub ( zigbee2mqtt) NAS, database and visualization,weewx and energy monitoring - using arm arch on a little 10watt device … I also done AI incorporation as well with Mycroft ( like alexa) but that was done on a much bigger 64bit intel router board that has 8gigs of ram that device uses 18 watts. the dual core BPI-R1 or R2 was not quite enough for for running AI not enough memory – you can use my script for OEM you just have to modify the Mqtt to something OEM uses

1 Like