Webcore Piston Does Not Fire until I Edit and Save Again


1) Give a description of the problem
when i create a piston depending on the piston i guess (doesn’t happen with all), i make the piston and press save. The piston saves like it should but when i trigger the piston, the piston doesn’t fire. If i go back into the piston, press edit (not make any changes) then press save, the piston will work the next time it supposed to and will work fine until i make a change to it again, then i’ll have to go back into the piston, press edit and save to get it working. I don’t understand why it does that.

2) What is the expected behaviour?
Create and save the piston and the piston should work without having to press edit and save again.

3) What is happening/not happening?
Piston does not work until i press edit and save.

**4) Post a Green Snapshot of the piston!


I would do…

If switch changes to on —> trigger
Time is after sunset --> condition
Then do


What do you mean by doesn’t trigger? Do you meam it doesn’t run every time a switch event occurs? Or do you mean it doesn’t do what you expect it to?

When Switch 18's switch changes to on is evaluated it will only return true if the event that has caused the piston to run is for the Switch 18 device and the switch attribute, the value is on, and the value has changed. In order to be considered to have changed, last time the trigger condition was evaluated for a Switch 18 switch event the value must have been off.

Your piston only evaluates the trigger after sunset so it doesn’t see all the on/off events and may be out of sync. There may also be issues initialising it.

@Pantheon has already suggested a better approach.

In general, if you are defining an explicit trigger condition you should make sure the piston can reach the trigger when the event occurs, regardless of the value.


Thank you both very much but I’m going to try and be more clear. It doesn’t matter which way the piston is setup, whether I set it up with a restriction or the way that @Pantheon suggested. Any time I edit the piston and save it, it doesn’t work until I edit and save it again for some reason.


Any clues in the full log when you first save the piston?