Sun Angle

[rlebel]

Now that I finally have my Somfy shades linked to my ISY I was wondering how best to automatically lower them based on sun angle? The idea is to have them come down just before the sun starts directly coming in to the room, which of course varies with the time of year, without having a physical sun sensor (yes of course I also need to know if it is cloudy, but the weather station light sensor can tell me that, and besides I'm in Santa Monica it is is always sunny LOL). I don't think a fixed number of hours before/after sunrise or sunset will be correct.

 

Thanks

[stusviews]

A fixed number of hours before or after sunset will work (except for the rare cloudy SoCal day or coastal fog). How much time before sunset will depend on the particular direction the window faces. You may need to make a minor adjustment occasionally.

 

BTW, how are you interfacing the ISY with Somfy (e.g., RTS, IR, hard-wired)?

[apostolakisl]

A fixed number of hours before or after sunset will work (except for the rare cloudy SoCal day or coastal fog). How much time before sunset will depend on the particular direction the window faces. You may need to make a minor adjustment occasionally.

 

BTW, how are you interfacing the ISY with Somfy (e.g., RTS, IR, hard-wired)?

 

Well, kinda.  The time of year will alter things.  In the winter (in the northern hemisphere), the arc the sun follows will be further South, it will be shorter, and the sun will move on that arc at a different speed.  Santa Monica is fairly South, so it won't be as extreme an issue as say Seattle.

 

There are programs that tell you exactly where the sun will be on any day of the year at any geographic location at any time.  If you really want to nail it down, you need to consult those programs, then alter your shades per the date.  Or you could just figure being off by a few minutes is no big deal and base it on a fixed time before/after sunset/rise.

[rlebel]

A fixed number of hours before or after sunset will work (except for the rare cloudy SoCal day or coastal fog). How much time before sunset will depend on the particular direction the window faces. You may need to make a minor adjustment occasionally.

 

BTW, how are you interfacing the ISY with Somfy (e.g., RTS, IR, hard-wired)?

 

Set it for fixed for now, will see how that works.

 

http://forum.universal-devices.com/topic/12762-isy994i-compatibility-with-twelve-somfy-motorized-shades/?p=115423