# Optional Expression

An optional write connection. Assign a write expression to this connection.

The application calculates the value of the expression and writes the result to the Value connection. All write expressions must contain a question mark (?) as a placeholder for the value the operator enters at run time.

If the decimal point type is Fixed position, and the "Digits after decimal point" value is not 0, the decimal point is removed from the displayed value and the resulting value is used.