PARIS, Jan 16 (Reuters) - French nuclear operator EDF's 900 megawatt (MW) Gravelines 3 reactor in northern France went offline Monday following an "unsatisfactory" result on a test of one of the functions of the safety system, the utility said.

The shutdown has no impact on the safety of the installations or the environment, and maintenance teams are carrying out checks to enable production to be restarted as soon as possible, EDF said.

The initial expected restart date has been pegged for Wednesday. French nuclear availability was at 75% of total capacity early Monday morning. (Reporting by Forrest Crellin; Editing by Jan Harvey)