In your opinion, the ePMP is waterproof if the cap not arrive to the end
(See image 2)
Or I need to remove it and vulcanize?
I don't like when they have no cover on all the head. For my part what i do i cut a piece of inner tube rubber and i glue it over the antenna connector and drop it over the radio. So the rain not fall directly on it. Cheap and efficient :)
If you loosen the 'nut' around one of the antenna connectors on the radio and raise the washer underneath that you can see a red O-ring intended to seal the housing around the SMA connector. Generally I would trust that to hold out water unless the whole radio is submerged, at which point the antenna connector is the least worry...
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The caps alone will let water in, and you'll end up with water ingress in the connectors.
These UBNT jumpers are actually semi-rigid cable (tin-soaked braid), so the cable itself is water-tight, and the connectors being soldered to the cable, makes water ingress trough the back less of a problem.
The main way water enters (in my experience) sma connectors is trough the screwhead due to impromer mating-torqueing. (Finger-tight is not enough.). You should always give it a quarter-turn with a wrench to make sure the rubber-seal inside the screwhead is properly set.
Particularly, after all that, i always fill the silicone cap with "liquid rubber / liquid insulating tape". When pushed in place the liquid rubber squeezes trough the front and the back of the cap sealing everything.
I have sites where we have condensation 300 days a year, running with installs like that for 5 years without a failure.
Self-amalgamating tape is good, but you have to be carefull and experienced to properly seal a fragile cable and small SMA connector, at times in tight and complicated spaces... Plus in cold days tape can give you a hard time.
I'll find some pictures and post here shortly.