A lot of Unifi access points run with 24 supply voltage. Some people seem to brick them with supplying 48V POE. Fortunately they have a over voltage diode which can be replaced easily.
UAP AC Lite
- remove and/or replace Diode D6
https://de.ifixit.com/Anleitung/Ubiquiti+UniFi+AP+AC+Lite+TVS+Diode+Replacement/73360
UAP AC LR
- remove/replace Diode D1
Spare Part for D1, D6
LittleFuse TVS Diode Uni-Directional SMBJ24A-E3/52 38.9V, 600W, DO-214AA 2-Pin
http://www.littelfuse.com/~/media/electronics/product_catalogs/littelfuse_tvs_diode_catalog.pdf.pdf