Programming suggestions for Weatherflow

[GQuack]

Greetings, I had my original Weatherflow Air and Sky system working fine and just replaced them with the new Tempest, also working fine. I haven't yet started using the data in programs but expect to soon. Can anyone point me to some good info on do's and don't's for programming? I've looked at the options for the devices and here is an example: if I want an action to take place once the wind hits a certain velocity, I would have expected that to be a "control" condition not a status, but control is not available. If I have gusting wind and certain actions to take once it gets too high or conversely too low, does each change in velocity get reported? I'm uncertain as to what is considered a "reportable" event to the ISY. If I don't do things correctly I could see actions happening more frequently than necessary since I live in an area subject to gusting conditions.

Temperature would be another question. Once temperature hits a certain threshold, turn on fans as one example. Once the temperature goes lower than the threshold, turn off the fans. If I have a cloudy day and the temperature is widely variable, will the fans be turning on,  then turning off in another 10 minutes then turning back on in 15? 

I'm thinking wide use of variables as I do for most everything anyway would play a role here and using a range of values seems reasonable rather than setting too tight of an upper and lower threshold.

Any thoughts or links to good information would be appreciated since I haven't found anything yet that focuses on the programming side.

[bpwwer]

All of the weather conditions are considered status.   Control would be used for things that don't really have a current status.  Something like a lightning strike event could be a control, but the distance to the strike is a status.  But I haven't created any controls in the WeatherFlow node server.

Any program that triggers on a status, will get executed when the status value changes.  So yes, if you had something like:

if temperature > 76
then
    turn on fan
else
    turn off fan

would cause the fan to turn on/off every time the changed going above/below that limit.  To prevent that you either need to guard band the value I.E. have the on temperature >  than the off temperature or add time references so that it has to be above or below the threshold for some amount of time before switching.

The node server is getting updates from the WeatherFlow hub at 1 minute intervals so that does limit somewhat how often things can change.

[GQuack]

Thanks bpwwer, pretty much as I expected, I need to think this through how to do things the best way. It is interesting when the items to monitor are more analog in terms of behavior than digital. What will be helpful is that my first area of interest will be temperature which should be less volatile than something like wind so I should be able to learn a bit from how that behaves and adjust accordingly.

[bpwwer]

I had a whole house fan set up with a bunch of rules including indoor/outdoor temperature.  At one point I got it stuck in a loop where it would turn on, blow some air over the HVAC thermostat which would cause an indoor temperature change which would turn off the fan.  Once it stopped the temperature changed again and the fan would turn back on. Probably not good cycling the fan like that.   It took some playing around with temperatures to get it working right.   It was pretty cool when it did.  I had it also tied to window state so when the indoor and outdoor temp was about the same I could open some windows and then when there was enough of a difference the fan would come on and start cooling things down. And if it ever got too cold inside, it would shut the fan off, or in the morning when it started getting too warm outside, it would shut the fan off so that we wouldn't pull warm air into the house.  Basically all we had to do to control the fan was open/close windows.

[GQuack]

Wow, makes my brain hurt just to think through all those scenarios! My wife is already saying, if you’re gone, what would I do if something doesn’t work? It’s a good question and when my old ISY gave up the ghost and I looked at the things that were not working or I couldn’t control because of that, I started putting more thought into Plan B, and C, and D with alternate ways of doing things.