I recently bought a house. In the dinning room, the previous owners added a gfci outlet connected to a gfci breaker. What might they have used this for? I can’t seem to find any relevant case. Location is Lafayette, IN.
With a GFCI breaker no other GFCI device is needed and sometimes a second GFCI device can cause nuisance tripping. I have seen a DIY person that did not understand put close to 50 GFCI outlets in his home that only had 5 or 6 branch circuits and thought he had miswired because now he was constantly tripping them. So why was a GFCI outlet added to a GFCI protected branch circuit? Probably because the person did not understand how they work.