Entering Next Higher Effects

During the FMECA analysis failure modes of product tree items should be specified. For each failure mode it's consequences should be specified - Next Higher Effects and End Effects. See FMECA Basics paragraph for more explanations and examples.

For one failure mode multiple NHE may be specified, for each NHE the affecting assembly should be specified.

RAM Commander FMECA allows very high flexibility of FM-NHE-EE chain definition and supports the following cases:

A.	simplest case - Failure Mode has a single effect (NHE) on a single higher level assembly, which in turn has single effect on the whole system level (EE) - for example FM "A" causes NHE "B" which causes EE "C":

FMECA_NHE1a

Failure Mode affects an assembly other than the parent assembly (for example some failure of hydraulic system affects some assembly power engine system, or for example you wish to specify that component failure affects the whole system without specifying all the effects on the block/assembly/subsystem etc. of that component).

C.	a single Failure Mode has multiple consequences (NHE) - for example failure mode "A" may cause NHE "B" or NHE "C" or NHE "D", each with its own conditional probability:

FMECA_NHE2a

D.	Failure Mode consequences are described by a long FM-NHE-EE chain - for example Failure Mode "A" causes NHE "B" which in turn causes NHE "C" which in turn causes EE "D":

It is up to the user to take a decision about the product tree level where Failure Modes are specified and how (on which tree level and with which level detalization) their consequences (Next Higher Effects) are defined.

The next paragraphs will explain how to define all the mentioned FM-NHE-EE definition cases (A, B, C, D).