Specifies the source of the Value property of this Alarm's User Field. Possible values for this property are 0 - evsInherited: The Value property is inherited from the Alarm Server or from the parent Area (default), 1 - evsLink: The Value property is provided by the Link property, or 2 - evsForcedValue: The Value property is a user-provided value. This property accepts writings with this object active, as well as inactive. In both cases, users cannot write the evsLink value. To change this property to evsLink, users must write directly to the Link property, that is, deactivate this object if at run time.