479 %-change of measured values

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Proposer: Jochen Haude , RWE

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Category: Issue for edition 2 of this part

Issue: (Question only)
Is there some idea for the Edition 2, how to model the "relative change of a measurand in some defined time interval" (gradient of a measurand) and also the status message, if some gradient-limit is exceeded ? For a lot of measurands the gradient is more important, than the absolute value, especially in monitoring systems.

Proposal:

Discussion	Created	Status ?	Ballot until	Editor
	09 May 07	green		Siemens AG Henry Dawidczak
	10 Apr 07	final proposal	09 May 07	Siemens AG Henry Dawidczak
	10 Apr 07	final proposal	09	Siemens AG Henry Dawidczak
It is understood that these changes happen slowly and are used not for protection (like df/dt) but for monitoring. Therefore, this issue may be solved by adding a new calculation method ("trend")in the statistical nodes.	23 Mar 07	red		ABB Klaus-Peter Brand