Detect when room is dark?

[paul warshawsky]

I don't know if this is possible.  I would like for activehome to turn on certain lights betwen certain hours, but only if it is dark in the room.  These rooms are well lit when it is sunny, but can be quite gloomy when overcast.  I can't find any product that can be set to send a macro trigger when a certain threshold of dimness is crossed.  Does this exist?

Thanks,

Paul

[hostilejava]

The MS13a and MS14a will send on/off commands to the next unit code higher to turn lights on at dusk and off at dawn.  Perhaps you can use those to setup your macros?

[jkarney]

paul
I too wondered about the same thing. I plan on doing this with a motion sensor using the dusk/dawn feature which sends a unit code +1. I am using a MS16A sensor in my system. I use this motion sensor to trigger macros that set flags to tell if I'm Home or Away. A dummy module using a timer is set to trigger my lighting macro 20 min before dusk. Depending upon if I'm home or away the appropriate macro will run. Currently I'm not using the dusk/dawn feature, but in my mind using a smart macro, flags, and the dummy module using a timer I think I can get it to work and run the lighting macro if the lights need to come on earlier if it's an overcast day.

Right now I'm stuck in a mental ground loop.   I'm over thinking this project.  :-

TTA and Puck have planted the idea of using the dawn/dusk feature on a motion sensor. Search the forum and you will find various ideas on motion sensor dusk/dawn feature.
In the mean time TTA posted a wonderful motion sensor comparion chart that is very helpful.
     

I always use this chart because it's more complete (and possibly accurate):

Comparison of X10 Motion Sensors

In the mean time I will be working on trying to figure this one out. Christmas will slow me down a little. But I will post my results as soon as I can.

Cheers 

[HA Dave]

I would like for activehome to turn on certain lights betwen certain hours, but only if it is dark in the room.  These rooms are well lit when it is sunny, but can be quite gloomy when overcast.  I can't find any product that can be set to send a macro trigger when a certain threshold of dimness is crossed.  Does this exist?[/size]

The dual floodlight (PR511) has a motion/darkness sensor. It can be triggered by ether motion or darkness (or both) and the level of darkness (from low light to actual dark) can be adjusted (it has a dial).

Darkness (light) can trigger up to four different unit codes (sensor code + 4-8) and motion can trigger four (unit + 1-4). See the manual for more info:  http://software.x10.com/pub/manuals/pr511.pdf

[TakeTheActive]

...I would like for activehome to turn on certain lights betwen certain hours, but only if it is dark in the room... ...I can't find any product that can be set to send a macro trigger when a certain threshold of dimness is crossed.  Does this exist?

Personally, for your application, I would avoid the Battery-Powered MS1x Sensors and go with something wired:

• Direct PLC connection, eliminating the potentially intermittent RF middleman
  
  
• No maintenance (batteries to replace)
  

In that arena, you have two choices: PR511 Floodlights and SD533 Sundowner. Each will give you the ability to control 4 consecutive addresses via light sensing. With the PR511 Floodlights, you'll have to go outside, climb a ladder, and install it. With the SD533 Sundowner, pick a window (I use my PR511 that faces WEST to sense Dusk/Dawn) and plug it in.

Now, although you "could" control 4 devices directly with either, I wouldn't. With my 2nd PR511 install (detailed in another thread "somewhere" here), I SEPARATED the Light Sensor/Motion Detect circuit from the actual floodlamp sockets (i.e. I didn't connect the internal relay) and instead wired the floodlamps to a WS467. I use Base+4 and Base+5 to detect Motion and Light, respectively. And they trigger MACROs. This, IMO, gives you MUCH more flexibility.

If/when you return, we can go into this further if you're interested...