Hi, I recently bought an EmonPi and I was able to set it up without a problem. Now I want to move it to a location where there is no Wifi coverage.
I was wondering if I would be able to use a 4G dongle out of the box. And if so:
-is there one in particular which you would recommend.
-can I use one of those 4 usb ports
Since 15 days have passed without a reply, I’ll say what I know. I’ve a 3G dongle on a Pi. It works transparently in so far as I can make a get request in python and it gets sent. If the WiFi is off it still goes. However I’ve discovered that an http request involves a lot of data overhead and on my pay as go SIM is not economical. I suspect MQTT is the answer as once it connects theres little overhead per message.
for SIM connections on my devices I generally used RSYNC and compressed appended data ( CSV) . and send every 5 minutes that way if it 100kb of data it generally ends up being only around 4kb - but you can not send to cloud directly you send to another machine that not on a SIM network that translates and then send to your cloud appliance- which works better as you maintain your own secure connection
Thanks @Clinkerr, yes should all work transparently as you have found.
I’ve recently installed a 3G connected system and am having trouble with high data use, it may be being caused by the shellhub remote access client that I installed on the system, I need to have another look at it and work out whats going on. @glyn.hudson and I did install another system on 3G a while back with better results, sending via HTTP but with a long bulk send interval as configured in emonhub.conf emonhub/emonhub.conf at master · openenergymonitor/emonhub · GitHub
In theory MQTT should be better, but it is sending key names so it would be worthwhile benchmarking the different approaches.
Thats a good solution.
There is a long open pull request to add gzip compression to the http interfacer in emonhub that I need to look at, it looks like it needs a bit more work to work with python3. Support data gzip compression in EmonHubEmoncmsHTTPInterfacer by SeanDS · Pull Request #70 · openenergymonitor/emonhub · GitHub