@Hank21 IVe used a few different POE switches 4+4 port TP link POE, 8 Port POE TP Link POE, Netgear 16 POE GS116LP,  24 port Zyxel GS1920HP. I used the supplied PSU that came in the box of the EAP 650 AP and it worked fine. EAP 650 didnt come with a POE injector. Only a 12v dc psu which I connected directly to the AP. When the AP was connected to POE, you can see the status led on the AP goes out and back on every few minutes. Ive done a few firmware updates on the AP and my Software based SDN controller but its still the same

  @Hank21 I returned the 2 EAP 650 back to my supplier as there was nothing I could do and I needed to fit them on site. 

I ordered 1 EAP 653 which is only different in that it doesn't come with a 12v PSU in the box so you save a bit of money. I never use the PSU for the AP's (I do use them for other things but it works out quite expensive).

I fitted the 653 and it works fine. Same POE switch and no problems. The 653 is also HW 1.0 same as the faulty 650's

@Hank21 Hi I just tried to setup our new EAP650s (upgrading from CAP1750s) and have exactly the same problem with all APs on a Netgear POE Switch GS324P. The CAP1750 just worked fine for years but the new EAP650 (with a Omada OC300) just... Are there more faulty devices? Is this a general issue? What do I do?

@Virgo Thanks so much for the quick reply. Unfortunately the Netgear is unmanaged, as it is a backup for our T2600G-28MPS, that is in service at TP-Link for some weeks now...

  @Jag1996 Interesting. I sent my devices back to my supplier here in the UK. They tested them and said there was no problems with them and sent them back to me. I haven't had a chance to re test them but I ill see if I can change POE class and try again. I have Zyxel ZS1920HP which I can test it on. Its very strange because on the exact same cable, I had an EAP 225 which worked fine. Then the 650s which didn't. Then 610 which did and currently 653 which has been there for months without problem. Doesn't make sense that the 650s' don't work.

I decided to check them again. Its still the same problem. What I have noticed is that the device is asking for poe class 2. I cant change that. My other EAP's are asking for class 3 or 4. What I have also noticed is that if I don't connect it to a cloud or software controller it works ok. The moment I adopt it into a cloud or software controller, it will reboot every 3 minutes or so. I haven't tried it with a hardware controller. I setup a new could based controller and it was the same issue. I even tried a complete fresh install of my software controller.This is such a waste of time. I shouldnt be spending hours to resolve this. My supplier should have just given me new units. TP Link technical support is also pretty useless in the UK. I am an installer and I use Omada over Ubiquiti. Most of the other installers I talk to think I'm a bit weird for using TP Link over Ubiquiti. I have done about 10 sites with full Omada. Routers, Switches EAPs. Im a bit disappointed with my supplier and TP Link tbh.