If you have a simple roof automation, maybe a garage-door system, there is an effective way to close the roof in case of unsafe weather, including sunrise, with no risk of opening it again (unless manually, for the next session).
The risk with this simple systems is inadvertently opening the roof, as a simple pulse will also open it if closed. We’re going to avoid it.
The elements we need:
- a CloudWatcher, that will close its internal relay when the weather becomes unsafe
- a small timer relay, such as this one from Amazon, that will make the change in the CW relay a timed one, that is, a short pulse, as usually needed to activate the roof.
- a limit switch (we have a few models in our shop, anything that will close when the roof is open will do).
- a small 12V power supply
- Starting from the power supply, the “+” side, goes to one terminal of the limit switch,
- From the other terminal of the limit switch to one of the CW relay terminals,
- and from the other terminal of the CW relay to the timer relay.
- The “-” or ground from the power supply, directly to the timer relay. (at this point we have connected the timer relay to the power supply, via 2 switches)
- Last, the “com” and “no” (normally open) connections of the timer relay, go to our garage system push button.
With this setup, if the roof is open, and the CW signals unsafe, then and only then, the timer relay will generate a pulse, that will (hopefully!) close the roof.
As soon as the roof is not open, it does not matter if the CW signals safe or unsafe again, as the circuit will be open.
While this is far from failproof (for example, we’re not warned if the roof fails to close for whatever reason), it is really an improvement to a simple “button pushing” action.