The radio/poe power is completely isolated from the control power (which comes from the base unit) on the 4 channel gigabit poe's, and the power for the PoE's defaults to on without a control voltage. The base unit currently only works on positive voltages.
One of the options we're looking at on the rackinjector is providing some internal terminals for a small DC-DC converter which would be mounted either on or just behind the control board. On Sat, Apr 14, 2018 at 8:16 PM, Seth Mattinen <[email protected]> wrote: > On 4/14/18 6:09 PM, Forrest Christian (List Account) wrote: > >> For various reasons you need positive voltage if you're doing traditional >> power-interruption canopy style sync. I.E. the type of sync which the >> PowerInjector+Sync will do. This general statement might not be 100% true >> with the 450i (and perhaps some other more recent radios), but suffice it >> to say that negative voltages aren't easy to deal with for sync. Because >> of this requirement the PIPS requires positive power. >> >> > Makes sense. I was thinking about using some to power stuff that doesn't > need sync (licensed radios) since I had them on hand instead of buying > something. Does the power only SiteMonitor 4 Channel Gigabit PoE Injector & > Controller will work fine with -48VDC or does its control power come over > the bus connectors from the base unit? But then I think I remember a thread > where the sitemonitor base unit itself only works with positive voltages. > > > On the rackinjector, we support the newer Cambium style sync, which >> doesn't much care about polarity, and also a polarity agnostic board which >> also doesn't care about polarity. For this reason, you can feed negative >> voltages into the rackinjector. Currently, you have to have at least one >> of the three power supplies feeding the rackinjector set up for positive >> voltage, and the other two can be positive or negative or whatever you >> want, depending on the requirements of the expansion cards and the radios. >> >> > No problem for me to throw a small DC-DC converter in the mix and feed it > a positive voltage on one of the inputs for controls. > > ~Seth > -- *Forrest Christian* *CEO**, PacketFlux Technologies, Inc.* Tel: 406-449-3345 | Address: 3577 Countryside Road, Helena, MT 59602 [email protected] | http://www.packetflux.com <http://www.linkedin.com/in/fwchristian> <http://facebook.com/packetflux> <http://twitter.com/@packetflux>
