The following graphic shows the change process in the request phase.

The process is always started by checking the ECR (engineering change request) and ends with its conversion to the ECO (engineering change order).

This conversion can only take place if:

• you have specified when the change should take place
  (Valid- from date, or values for the effectivity type parameters with a new effectivity type)

• a digital signature is made (if applicable)
  (depending on the definition of the effectivity type)