Expression Variable Condition

The Expression Variable condition tests the value of a specified Expression in the current ReactorSensor.

All of the same operators available to Device State conditions are available except updates, so it is possible to make both string and mathematical comparisons. It is also possible to use variable references in the operand(s).

The expression/variable must exist at the time the condition is created. You will need to visit the Expressions tab to create your variable prior to creating an instance of this condition type.

This new feature of version 3.5 is a shortcut. Prior to 3.5, testing a variable/expression had to be done by using a self-referencing Device State condition, and the expression had to be marked for export. As of 3.5, any variable/expression can be tested using the "Expression Variable" condition type, and it is not necessary to export the variable.

If you want to test an expression/variable in a different ReactorSensor, use the Device State condition. The expression must also be marked for export in that ReactorSensor.

You're Doing It Wrong!

If you are using an Expression Variable condition to test an expression that contains only a getstate() function call and no other arithmetic, that's just a less efficient way of doing a Device State condition.