Field help (FASMAXDEP) 

Limit of depreciations calculation beyond which, these are no longer tax deductible (ex: private vehicles).
By default, the application suggests the limit associated to the category on which depends the fixed asset. This field is accessible in modification only if its category is also set up with a limit. It is up to the user to suggest another value in case of tax modification.
This amount is used in the AMOREINT report (fixed assets to reintegrate).