-
Notifications
You must be signed in to change notification settings - Fork 103
FAQ & Troubleshooting
This documentation is for software version 0.2.0 and earlier. Click here to see this page in the latest docs.
-
Does it matter which direction the current transformer is installed over a wire?
-
My CT is installed over a wire, but I'm not seeing any data. Why?
-
Can this project monitor DC power (batteries and solar panels)?
Yes. This project requires a step down AC transformer to bring your local grid voltage down to ~ 9V AC so that grid voltage samples can be taken safely. A 120V to 9V AC transformer is available in my shop.
Yes. Some CTs have an arrow stamped or marked on the clamp itself. This arrow is supposed to indicate the direction that current flows from the CT's perspective. However, if you wired the CT to the board yourself, it's possible that the connection was made backwards, so the arrow marking on the CT would be meaningless in this case.
All CT readings for Watts and Current should be positive^ when displayed in "terminal" mode.
^ Exception: If your monitoring implementation has any source of production and you also export power into the grid, it is expected that your mains occasionally report negative readings during times of net production. In this case, the CT should show a positive reading at times of net-consumption and a negative reading at times of net-production.
The most likely reason is that you have the CT installed over a cable that has multiple conductors inside. The CT only works when installed over a single conductor. In a standard 120V US electrical system, this would be the black or red "hot" wire.
Power strips and extension cables usually have 3 conductors inside them. To directly measure an extension cable/power strip, you'll need to place the CT over the hot wire only. This may require some cable modification - do so at your own risk, and NEVER work on anything energized!
The project as currently published is only for AC power monitoring. (DC support might be coming in the future).
This can happen for a couple of different reasons. First - the software could be running in the background via the service file, and you might be trying to start the software manually in phase or debug mode, essentially running two copies of the software that are trying to access the same resources. Check if the service file is running the software with: sudo systemctl status power-monitor.
Second, your Pi might be running an older version of the Python spidev driver. Check the version with pip freeze | grep spidev. If you don't have version 3.6 or newer, update spidev with pip install -U spidev. If you get a message about setuptools, try updating pip first with pip install -U pip, and then try updating spidev again.
TBD