Wind direction is something that we use a lot and if the offset changes for whatever reason, we need to know about it, so that we can reset it and update the readings for the period where the offset was possibly changed?
Another scenario for us is "What is the deployment of the WeatherFlow device is incorrectly done, we need to be able to correct the offset readings once discovered.
Because we are using these devices to facilitate environmental compliance, where the devices are placed outdoors in remote area’s they can be tampered with or animals may accidentally tamper with them (think buck brushing against mounting), which is another reason we monitor them every 24 hours and why Wind Direction Offset is so important to us.
the wind direction offset should never change. You set it once, because you didn’t orient the unit quite in the right direction. If the api would tell you the offset is 10 degrees, you learned nothing about the data, only that the unit wasn’t oriented correctly when mounted. As you don’t change it more than once, there seems no need for this api call.
Not that I am against it, but I don’t see the use case.
I agree with your completely, however we have seen it change on our side on two separate devices where on two separate occasions, and this is after have ensured that a standard operating procedure has been implemented and followed.
We can’t explain how the offset was changed and there is no log of the offset, hence the request for the API update.
Thanks for sharing your thoughts though. Much appreciated.
To achieve sanity of the data at all times this would require that the device have a HMC5883L built-in compass so that as long as the device is standing up it is going to be able to return clean~ish data. The compass direction arrow would then only be a reference to point away from the sun’s track (north or south hemisphere).
Other considerations would be interference if placed on a large metal structure, devices that change the electrical field around the device installation, etc, potentially the pole the device is mounted on.
I work with people with quite remote devices that will only be seen once every year and this would be a good feature that could also provide a tuning of the dataset across the installation base - math differences between grid north and magnetic north not withstanding.
The combination of direction of the device (which way the solar panels are facing) and the compass facing could also trigger an alarm if the solar panels have been moved away from the track of the sun before the battery dies - an alignment error letting the owner know they have an issue before the station runs down on battery…
Alternatively through some backend code the profile of the battery charging on two clear days within a space of a week would be expected to be quite similar unless the unit is rotated by maybe ~45 degrees. Then you would be able to pick up a shift in charge profile alone but it would be very much weather dependent. You could also cluster data within a catchment in the cloud and identify several markers for a device that may be an outlier. This wouldn’t be very accurate (depending on technical standard required for records) but you could look at the dataset without any change to the hardware.
probably easier is to just compare the wind average with the predicted wind average. No compass needed (that would need calibration anyway, like you phone does). For something that isn’t supposed to happen (rotating the device), adding a compass just adds more components that might fail.