Suggestions?

Developer's Corner Scene Scripting
1

Have an outside tap that cannot be shut off during the winter months. When it gets cold outside I can plug a heat tape in to prevent it from freezing.
Recently installed the EDS OW-server to monitor temperatures and the vera plugin, works great
Plan is to create a scene when the temperature goes below 3 degrees C. the outlet turns on and the heat tape comes alive. Like wise another scene to turn off the outlet at temperatures above 5 degrees C.
Question is when the temperature reaches the trigger temperature of the scene will the scene keep firing as the temp keeps dropping or rising or do I need to care if it keeps on firing or does it just fire once?
If the trigger only occurs once at the desired temp I was considering of adding this code as the temp toggles between 3 and 3.1 degrees for example. The scene will not refire if active within the last 2 min. Again will the outlet really care if it gets the command to turn on again when it is really on.

local result = true
local now = os.time()
if (LastTime) then
result = now - LastTime > 120
end
LastTime = now
return result

Thinking it just really boils down to saving CPU cycles in my vera lite and reducing RF in the house.
Thanks for any comments or suggestions.

2

Should not hurt to send an ON command to a switch that is already on.

Of course you need a second scene to handle turning it off as well.

If you want to make sure you only send 1 command … you can use the PLEG with two conditions.
They will only fire the actions once when the condition is satisified:
i.e.
HeatOn Temp < 3.0
HeafOff Temp > 4.0

You do not need to have an outdoor thermometer … you can use the Weather Plugin for temperatures in your area.

I actually do this as well … but for me it’s turning on a circulation pump 15 minutes/hour when the temperature is below 35F. This is to circulate water between the Rain Water Storage tanks and the House (Some pipes exposed). A side benefit is that I also run the water though the filters.

3

Thanks Richard for the comments. Already have the WX plugin but since I have my new toy the OW-Server :slight_smile: I thought I would use it since I have a temperature sensor already attached to the faucet. In the winter I have a cover over it and with the heat of the house it seems to stay a little higher than the ambient temp outside. Never used PLEG but it looks like a good time to take a look at it. Time to search for info. Thanks