Log Locally


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Data can now be logged to Emoncms runnning on the emonPi’s local server, data will be saved to the Raspberry Pi’s SD card.

Data can also (optionally) be posted remotely to Emoncms.org, see Next step: Log Remotely.

For application specific input processing see:

  • Login to Local Emoncms http://emonpi/ (or local IP address)
  • Navigate to Setup > Inputs

You should now see an updating input list of connected nodes (e.g emonPi, emonTx, emonTH) and they keys (e.g. power1, power2 etc.) together with the last received value. If you do not, see Setup > Troubleshooting.

Input data is not saved to disk. To save an input Emoncms Input Processing is used to log an input to a Feed. Feed data is then logged persistantly to disk. To log an Input to a Feed:

  • Click on the Input Config Spanner next to the input you wish to log to a Feed:

Emoncms Inputs

  • Process List setup box will open
  • Choose required Input Process e.g Log to Feed
  • Create a new feed giving it a name e.g. use or log to an existing feed *
  • Select the default PHPFINA Feed Engine
  • Select a logging interval e.g. 10s **
  • Click add to Add to add that input process

Input Processing Power

If logging a Power value input you will also want to create a corresponding KWh Feed. This is done by adding another input process:

  • Choose Power to KWh Input Process
  • Create a new KWh feed e.g. use_kwh *

Input Processing kwh

  • Once required input processes have been added click Changed, Press to Save
  • Then Close the Input List window

Input Processes List View

  • The Inputs page should now display the active input processes in the Process list column

Input View with processing

  • Navigate to Setup > Feeds
  • Updating feeds should now be visible

Feed View

  • To view the feed data click the Eye Icon
  • This will open Data Viewer
  • Multiple feeds can be overlayed on the same graph by checking the boxes on the right hand side
  • To view daily data see Emoncms > Daily KWh.

Note: no data will be visible immediately. Wait a few hours to build up some data before trying to view a feed.

Feed Viewer

* Using standard feed names such as use, use_kwh, solar, solar_kwh import and import_kwh (case sensitive) will automate the setup of MyElectric, MySolar PV and Android app dashboards. See Setup > Dashboards and Home Energy and Solar PV applications pages for more info.

** Feed interval loging time should not be less (faster) then the default node update rate. Choosing a longer (slower) update rate is fine and will conserve disk space:

Node Max Update Rate
emonPi 5s
emonTx 10s
emonTH 60s

We recommend making regular backups of local data. See Setup > Import/Backup.

Video Guide



Next step: Log Remotely »