Wireless Access

I'm working on my first outdoor install of AP-275s and have a question regarding lightning protection.  I have 3 outdoor rated cat6 cable in buried conduit going from an inside IDF to the APs.  There's roughly 50ft of cable from the IDF to the building's egress point, and 150ft from the perimeter to light poles where the APs are installed. Inside the poles, the cable connects to a grounded, POE rated lightning arrestor, and then a patch cable from the arrestor up the pole to the AP.  We also have a lightning arrestor at the other end of the cable in the IDF to protect the switch.  We're having issues with water getting into the light poles and into the RJ45 connections on the arrestors.  Instead of trying to figure out how to waterproof the arrestor and its connections, I'm thinking of removing the lightning arrestor inside the pole and just running the cat6 straight to the AP so I don't have to worry about water inside the pole.

BEFORE:

IDF([LA])--50ft--(building egress)----150ft----pole([LA]---[AP])

AFTER:

IDF([LA])--50ft--(building egress)----150ft----pole([AP])

I feel like arrestors at both ends isn't necessary, but as I stated before this is new territory for me.  So how many arrestors would you install and where?

First and foremost, local CE should be sought out on the rules and regulations on how equipment should be grounded, as different regions and localities have their own rules and regulations. 

That said, I think grounding at the AP shouldn't be necessary, the only protection the LAs at the APs offer is to protect other lines run through the same conduit. However, if other drops and network cables are run through the conduit, you may want to keep the LAs in place to protect other devices who's cables are within the same conduit. But if it's just the three AP network cables through the conduit, I would think you should be fine removing the LAs. 

But again, local CE is the final authority.

I ended up pulling the lightning arrestors out of the poles and left the other upstream lightning arrestors inside the building.

Having lightning arrestors inside the poles turned out to be a troubleshooting nightmare as they got wet and started corroding the RJ-45 pins on the patch cable and arrestor.  We started having really bad packet loss as a result.  I couldn't get any guarantee from the maintenance department that water would not get inside the poles.  So I just removed arrestors, connected the trenched able to AP patch cable inside the pole with a waterproof RJ-45 coupler.  I didn't have a good option for water proofing the arrestor, so this made most sense.  Future troubleshooting should be a bit easier since I have one less device to check when there are issues.