I don't has specific experience with the 450m, but based on various other radios through the years, the silicone may not be a good idea.
What sometimes happens is temperature changes cause pressure or vacuum inside the sealed enclosure, and when there's a vacuum, it will suck air and/or moisture in through any crack, including the cable gland. Even if it's just air, this can lead to condensation inside the radio. I'm guessing Cambium has one or more Goretex vents on the case, designed to let air in and out but not water. I remember people reporting that the original 450 (not 450i) had problems with water intrusion, in some cases due to improperly installed vents. I remember years ago Trango had problems with vacuum inside the case sucking water into their 5830 series APs, people were sealing with silicone, and that actually made the problem worse. Trango finally recommended leaving the cable gland a little loose so water could drip out the bottom, which isn't exactly a wonderful solution. Medusa is like a 450i on steroids, maybe with more air inside the vacuum effect when temperature drops is enhanced? If it's less than a year old, it might still be under warranty, I forget if that's 90 days or 1 year, assuming you didn't purchase an extended warranty. Even if it's out of warranty, but due to a manufacturing defect, you might talk Cambium into replacing or repairing it for free. -----Original Message----- From: AF <[email protected]> On Behalf Of Vlad Sedov Sent: Wednesday, October 10, 2018 2:30 PM To: [email protected] Subject: [AFMUG] PMP-450m taking on water?? So we had to climb one of our towers today to deal with a sudden intermittent ethernet issues with a Medusa that's less than a year old. We did just have a pretty good storm and were fearing the worst.. When the weather coupling on the cable got removed, a bit of water poured out, and the connector had obvious corrosion marks. A bit of cleanup and a new RJ45 later, the radio is kicking again... But it seems a bit weird that a $6000+ radio can't hold back a bit of rain. Last time we've seen this problem was with some older PTP600 and PTP400 radios, after the o-ring seal failed.. Some were full of oxidation and water damage. I hope it's just an isolated incident.... The climber added a bead of silicone around the perimeter of the radio to antenna seal it for now, but I wonder if it's worth opening a ticket with Cambium.. Not a happy camper right meow. cheers Vlad -- AF mailing list [email protected] http://af.afmug.com/mailman/listinfo/af_af.afmug.com -- AF mailing list [email protected] http://af.afmug.com/mailman/listinfo/af_af.afmug.com
