In pimatic I use a lot of devices where I would like to display and control there operating time. Currently this
is only possible with vraibles or timer device and acouple of rules.
Too keep the system easy managable it would be better to keep the amount of rules small.
My idea is to have a special device similar to thoses in the Filter plugin and to avoid any rules.
This device can be linked to a observable device and then automatically increments operating time, when the observable device is in state on.
Here my rough definition: