Sun Radiation / Sunset time shifted by 1h earlier?

Hello everybody,

Ive been playing with the openhab/influx/grafana stack for some months now and I really enjoy it ! Thank you very much for that.
Then, I suspect a strange behavior in the middle of this.
I recently added a simple light sensor outside the house to get an idea of how much light/sun is coming from the sky. It’s a simple LDR giving a 0-1024 value (green curve on the attachment). Mainly tuned for low light levels so the top of the curve is a little bit compressed.

I have also added astro channels like total radiation (light blue on the attachement above)(coming from the astro binding) and I am surprised it is not centered on my light level green curve.

  • Im drawing these two using grafana
  • The time indicated on the X axis is the local time (UTC+1, DST is on)
  • My coordinates are 48.7, 2.3
  • My system timezone is correct (Europe/Paris) as well as my system time:
    pi@raspberrypi:~ $ cat /etc/timezone
    pi@raspberrypi:~ $ date
    Wed 13 Nov 23:25:47 CET 2019
  • My location and timezone are also correct in paperUI

I also added some other channels to try to explain what was going on:

DateTime         Sunrise_Time       "Sunrise [%1$tH:%1$tM]"                   { channel="astro:sun:home:rise#start" }
DateTime         Sunset_Time        "Sunset [%1$tH:%1$tM]"                    { channel="astro:sun:home:set#start" }
DateTime         NightTime          "NightTime [%1$tH:%1$tM]"                      { channel="astro:sun:home:night#start" }
DateTime         DayLightStart      "Daylight start [%1$tH:%1$tM]"            { channel="astro:sun:home:daylight#start" }
DateTime         DayLightEnd        "Daylight end [%1$tH:%1$tM]"              { channel="astro:sun:home:daylight#end" }

This gives the following values for today (Nov 13rd):

Sunrise_Time changed from NULL to 2019-11-13T07:25:00.000+0100
Sunset_Time changed from NULL to 2019-11-13T16:15:00.000+0100
NightTime changed from NULL to 2019-11-13T18:18:00.000+0100
DayLightStart changed from NULL to 2019-11-13T07:29:00.000+0100
DayLightEnd changed from NULL to 2019-11-13T16:15:00.000+0100

The good thing is that these values are pretty consistent with the blue curve (radiation).
The other good thing is that sunrise time is also consistent with the green curve (actual light)
The bad thing is the sunset time doesn’t match the actual light or the “official” sunset time ( (and what I can see through the window).

Everything is like if the sunset time was incorrect (shifted by 1h earlier)

What did I miss ?

Thank you for your help !


Answering to myself…

I switched from “astro:sun:home:…” to “astro:sun:local:…” and it seems that does the job for the sunset time… A bit too late for radiation as it is nigh time now but my guess is it is now fixed. More to come tomorrow !


Summer time changes I presume. Can’t tell right away where exactly to look for, but I’d start
checking OH’s and your server’s timezone and as you already said the astro thing.
Eventually there’ also s another setting in InfluxDB/Grafana to affect this.

Check astro Things - this is two different Things. Most likely, one of your own creation and one auto-generated based on system defaults.

much better today :slight_smile: