dear all,
just receive my RB850Gx2 today and do some experiments…
the thing i found is this unit can not be powered up from RB750UP.
and my RB1100AHx2 also confirmed can not be power from RB750UP as well.
I am using poe-mode = auto-on on RB750UP.
can someone at Mikrotik @ Latvia to reconfirm that unit can not be powered from RB750UP ?
thank you
Paul
RB750UP can run from 8-30V
Supports PoE output on ports 2-5. Max current 500mA per port
So each port can give out from 4W - 15W depending on Power supply Voltage you use on RB750UP
RB850Gx2 Max Power consumption 8 W
So as long you power your RB750UP with 16+V ( calculating cable loss i would go 24V) power supply it should be ok
RB1100AHx2 max power consuption was ~30W if i remember correctly, so even theoretically you can’t powe it from RB750UP.
dear macgaiver,
my rb750up firmware has been upgraded into v2 so it can support up to 1A for ever ports; with total 2.2A for all ports. see http://wiki.mikrotik.com/wiki/Manual:PoE-Out for details.
i do not think there is a power problem on my RB750UP as I did power it up with 24VDC 2.5A, and both RB1100AHx2 and RB850Gx2 could not on. But they can on with normal small PoE unit even with 16VDC 1A power adaptor.
FYI.. I did try to power up my RB433UAH with 3 active R52HN from the same RB750UP with no problem.
the problem suspect is the resistance produce by PoE-in port on PPC family that can not trigger the power from RB750UP.
the wiki said “For power-on to happen there should be resistance on spare pairs in range from 3kΩ to 26.5kΩ.”
anyway, i have not test with force-on from RB750UP yet as I always use auto-on
updated:
i just try to change the PoE-out mode from auto-on into force-on and both of them can ON normally as it should be. RB1100AHx2 power consumption is 10.7W, and RB850Gx2 power consumption is 3.2W. both on idle state condition. so it seems really the resistance problem at PoE-in port on PPC family.
Paul