Events for Change Documents - FM For Event Id

[jerry martinek]

Hi,

I've looked at the help for the 'FM For Event Id' in the Events for Change Documents and unfortunately I don't understand the explanation. The explanation 

"This function module is used to determine event names from the data transferred by the change document. Its interface therefore has event names as output parameters and the change data which is to be saved as input parameters:" 

doesn't answer my question which is what is this function module used for.

What I need to do is to create a new triggering event if a requisition changes when the value of the change is less than 10% and there is no active workflow for a release relevant requisition.

This is an SAP 46C system.

I want to know whether change documents is the place to make this check.

Thanks,
Jerry