I know there has been lots of discussion about +48 vs -48, but I don't remember if this specific question has been answered. Can you power a 450i AP using -48V POE. I'm not talking about flipping the polarity, but using a power supply that has the + side tied to ground.
We converting a site that originally had Purewave WiMAX that requires -48V DC power so it was built with an Eltek Micropack rectifier system that puts out negative 48V DC. We have a DC-DC converter for a few pieces of equipment that require +24. I was assuming that I would have to temporarily put in another DC-DC for +48 to power a 3.65 GHz 450i AP (with AUX port sync if that matters), and then change out the Eltek to Traco once all the customers were moved off the WIMAX system. But it occurs to me that a lot of gigabit 802.3af/at powered equipment actually doesn't care which side of the POE power is grounded, or if it is grounded at all. So maybe I can keep the Eltek and power the 450i with one of Chuck's GIGE-POE-APC thingies. But I'm not brave enough to risk frying an expensive AP just to find out. For turnup I been using one of the Cambium AC powered indoor POEs, but this is a DC site so that can't be the permanent solution.
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