DateTime Calculations

[rossko57]

This has ideas

Store time in item, then calculate time past

I have put this together from a bunch of examples, but its not working… any ideas? //in Items file defined as DateTime plum_25_motionName_Last “Plum Basement Playroom [%1$ta %1$tR]” //set last motion stamp with this in a rule postUpdate( plum_26_motionName_Last, new DateTimeType() ) This does not work, trying to determine if its been more than 20 minutes since last motion rule "Check Date Time Stamp" when Item Kitchen_Movement changed to ON then var DateTime dateTime = new DateTim…