Hi Sander,
Edit the AP Zone or AP group or specific AP to check/modify it's TX power.
By default all APs run with full TX power.
Regards,
Syamantak Omer
Syamantak Omer | Community moderator | Staff TSE | CWNA | CCNA | RASZA | RICXI | Follow me at https://linkedin.com/in/syamantak-omer-5949b6124