22.93 is too low. Cambium says 23V is the minimum into the radio. See http://community.cambiumnetworks.com/t5/ePMP-Installation/ePMP-PoE-Powering-Primer/td-p/49944
You need to subtract a bit of loss inside the injector, and then a bit more for cabling. Plus a bit more for everything else. For verification, I took my bench ePMP and hooked it up to my power supply - it doesn't even turn on until 22.5V at the radio. I'm sure other copies are probably higher or lower. And I'm sure it changes with internal temperature of the radio. One big difference between the PoE Injector and the SyncInjector is that the syncinjector uses semiconductor switches which generally have a bit more voltage drop than a relay. The tradeoff is that the semiconductor switches can switch far more power than the relays can and can switch quickly enough to do sync over power. On Sat, May 12, 2018 at 10:26 PM, Josh Luthman <j...@imaginenetworksllc.com> wrote: > So we replaced all 8 surge cards. It's getting 22.95 and 22.93 for the > two boxes (to the green terminal). Devices are still rebooting... > > Epmp never has problems with the same DC supply through the green POE > injector, forgot to mention that. > > > Josh Luthman > Office: 937-552-2340 > Direct: 937-552-2343 > 1100 Wayne St > <https://maps.google.com/?q=1100+Wayne+St+Suite+1337+Troy,+OH+45373&entry=gmail&source=g> > Suite 1337 > <https://maps.google.com/?q=1100+Wayne+St+Suite+1337+Troy,+OH+45373&entry=gmail&source=g> > Troy, OH 45373 > <https://maps.google.com/?q=1100+Wayne+St+Suite+1337+Troy,+OH+45373&entry=gmail&source=g> > > On Sun, May 6, 2018 at 8:14 PM, George Skorup <george.sko...@cbcast.com> > wrote: > >> Funny story if you were using ePMP near the beginning. Some of the first >> original 5GHz integrated radios had labels marked 56VDC. They were >> definitely NOT capable of being powered from 48/56V. Somebody screwed up. >> >> Yeah. We've run Force180/200 survey setups on a small 12V SLA too. It >> works, but they're rated at 14 volts. Same with the 100 and 450 SMs. Still >> works. However, I recall the regulator is very inefficient down that low. >> Like the old 320 and 430 APs could be run on 24VDC, but you really didn't >> want to do that, and Motorola/Cambium said it was completely unsupported. >> >> >> On 5/6/2018 5:13 PM, Bill Prince wrote: >> >>> I had a portable 12V battery that I would use for site surveys with the >>> old PMP100. I'm pretty sure they would function in the 8-10V region. >>> >>> I know nothing about the ePMP radios. Trust George. >>> >>> >>> bp >>> <part15sbs{at}gmail{dot}com> >>> >>> On 5/6/2018 2:33 PM, George Skorup wrote: >>> >>>> Original 5GHz integrated and connectorized are 14-30VDC, -4/5 +7/8 only. >>>> >>> >>> >> > -- *Forrest Christian* *CEO**, PacketFlux Technologies, Inc.* Tel: 406-449-3345 | Address: 3577 Countryside Road, Helena, MT 59602 forre...@imach.com | http://www.packetflux.com <http://www.linkedin.com/in/fwchristian> <http://facebook.com/packetflux> <http://twitter.com/@packetflux>