@R1D2 

First, Thank you for your reply. I really appreciate the help. The 2nd question is solved. I didn't take into account half-duplex.

As for the first problem. When I wrote

and when I logged into the Pharos UI to check the Device was set to have a Static IP from the WAN

I meant LAN, Sorry.

What I don't understand is that if the CPE 510 AP had a misaligned antena, I would be experiencing packet loss connected to the AP. What I am experiencing is packet loss direectly connected to the switch when I connect the AP to the same switch. And I don't know if packet loss is the right term. What I am seeing is an intermittent ability to reach the gateway when the AP is connected to the same switch that I'm connected to via ehternet cable. When I remove the AP from  the switch. The network stabalizes. It doesn't make sense to me at all.

@R1D2 

Great Point. I didn't think it could be the client causing the issue or one of the devices behind the client. Here is what I'm going to do. I'm going to take all the devices off the netwrok behind the AP. I'm going to factory default the AP. I'm going to set it to a static IP. Reserve that IP on the Router. Test. And then setup the Client by setting it to a static IP, reserving it on the router, and also locking it to the AP. Test. Then setup the APs behind the Client. Test.

Thanks for your help!

@R1D2 

So I did all those things mentioned above. It worked for a couple of hours and then the CPE 510 in AP mode went down again. At this point I suspect that I'm attempting PoE over too long a distance. I have a 100FT Shielded Cat 6 cable that I'm running from outside the building to the POE  inside the building and then a short Cat 6 LAN to the switch.

Is it possible that this distance is to long for PoE. I read up on the standard and I thought PoE was usable up to 328FT. Regardless my plan now is to move the PoE connector closer to the AP in a weatherproof outside box next to the CPE510 and have the LAN run the 100ft to the switch. I this a good solution, or is it that my cable is bad and I need to run a new cable? When I tested the cable it was showing all channels were good. Any advice here would be greatly appreciated.

Edit: I forgot to mention that I'm extending the Wifi Network that is in the First building. It has the same SSID and Password as the EAPs in the first building. I don't think this should be a problem and I have the client 510 locked to the 510 AP, but I thought I'd mention it in case I'm missing something.

Edit #2: Here is the link to the cable I bought:

https://amzn.to/3iUiQFR

I'm starting to believe that it's the cable that is the problem. PoE 24V over 100FT should not be a problem, this cheap cable may not be able to handle the distance though.

@R1D2

What I got from your reply:

A) Use better shielded cable and gound the cpe with the shortest possible path
B) Because my main is potentially unstable locate the PoE injector as close to the CPE as possible
D) Put the AP and Client on a different SSID than the rest of the network

Questions:

1) Should I use maxstream between the AP and Client

2) I going to put an AC1200 on the same wall as the CPE510 AP. Is there a minimum distance away I should put the devices?
 

Edit: I know this might sound a little dumb but I have been setting my gateway and DND to my Router and not the AP. I believe this is correct but wanted to make sure.

Thank you for all your help. I would be stuck without you assistance.

Regards.

@R1D2 

I thought you'd like to know that the reason for the extreme network instability which was a rogue DHCP server in the form of an Apple Express that I didn't know was on the network. The slow speeds was due to the router not being set to foward DNS. Once I fixed thos issue speed was fine. Thanks for all your help.

I have another issue I was wondering if you could assist me with. I've put the inside and outside EAPs on the same SSID, let's call it Main Buidling. Inside there is one EAP 115 broadcasting this SSID on 2.4 and outsid their is an EAP AC1200 Broadcasting Mainbuilding in 2.4 and 5 hz. Outside is on a 100ft POE cable and Inside is on a 3 ft cable. They are both getting thier IP Addresses via DHCP.

1) My first question is how does a device decide which WAP to use? From my research this is based on detected signal strength and there is little I can do to affect that on the nework side correct? Some of the devices are prefering the outside signal to the inside signal.

2) How can I tell which AP I'm connected to if they share the sam SSID and they are bridging the LAN side of the network.

3) My third question is I am recieving low throughput connected to the Main Building 2.4 SSID when I'm inside the building. Any thought as to why the speeds might be intermittenty slow coming from the WAPs? I've tested wired into the switch and speeds remain stable 300/300 after the DNS fix, but connected to the AP I sometimes get 80/80 more often I get 3 to 4. Should I assign them static IPs? Could the Wifi signals be interfering with each other?

Edit 1: I came acoss another one of your forum posts, https://community.tp-link.com/en/business/forum/topic/202474?replyId=428282. I'm going to change the channels of my three 2.4 APs to 1, 6, and 11. I'm going to leave my 5hz on auto. I'm also going to reduce the singnalstrenth in the m ain building a little as to not interfere with the outside AP.

Thanks!