The above notwithstanding, it appears that they may have a rather funky cheat to get around the speed/power/cost problem with their
8 port gigabit passive PoE injector (am awaiting a return call to confirm). But it rather looks like the 'passive' applies to how it is not an active network device as such, but merely something that puts woema on (any) eight ports your heart desires, as coming from a completely bog-standard switch of your choice.
View attachment 88977
DANGER WILL ROBINSON!
So, having (had to, they failed at returning my call yesterday (but hey, work ends tomorrow, right?)) called them, and gotten some sense out of Guy in CPT (thank you again for your time), this is a thing I will never ever (EVER!) bring near any network of mine. It turns out that, aside from needing being to be fed power (obviously, it's an injector) it's passive all right, and dangerously (to your equipment) so, it:
- is NOT a network device, like a switch would be; it is invisible to the network a ghost (that shunts woema onto the wire) - so passive in the network device sense.
- has NO, none at all, integrated power intelligence, which is the the very essence (pdf, see graph on p20) of the 802.3 standard, it blindly, dumbly - passively - shunts power (itself a value derived from voltage AND current) onto the wire. To devices that are expecting the handshake sequence in order to power up.
- has no internal power management/regulation (guess derived from conversation): you feed it an input DC voltage, 12-48Vdc per their site, and ALL of that power is available on the wire - brute force, with no control. Related: it's apparently passive about just what VOLTS go on the wire, with there being a direct one-to-one relationship to input voltage, so: 12Vdc out for 12Vdc in, up to 48Vdc out for 48Vdc in; it seems this thing has no DC-DC converter to jack the input voltage up to the PoE standard (but then it apparently has nearly nothing in it anyway)
Here's
another visual for the handshake:
As if that weren't enough, they barely know about how (potentially) dangerous this thing is to the unschooled, they carry no warning on the product page, nothing about
"Use this 8 Port Passive PoE injector to power up 8 Passive GIGABIT PoE devices through a single power source. Ideal for powering AP's, IP cameras or VoIP phones. Power by DC jack or Terminal Block connector" (sic) carries any warning about its shortcomings.
And then they have no power for it anyway, you have to go and find one yourself somewhere else and mate to this monster; which you can, quite easily, from your local
electronics supplier, here a 150W/48Vdc PSU, easily good enough for eight 802.3af devices which, at 350mA/node, want a total of 2.8A. But 802.3at devices, with their 600mA tendencies at a 4.8A demand would swamp
this thing (pdf); no, to power a full house of .at devices, you would have to go up to
this beastie. (pdf) And both of those PSUs will just dump their full, regulated power onto the line, as designed. To devices that want an introduction before they wake up and work.
TL;DR: this thing is an utterly uncertified, non-compliant device that is an excellent, unnecessarily expensive (in terms of time and hassle) and entertainingly easy, way to blow (expensive) equipment up.
That said, if you are suitably careful it may be feasible, maybe with this
PoE passive splitter to pull the power off the wire at the PD end, and feed it the usual, expected power through its DC jack ..but why would you when it's just simpler and safer to go with properly certified hardware?
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The 'Key Features' tab lists that it has ONE (and only one) PoE port at port 8 and the 'Specifications' tab indicates that the 5Vdc power adapter it needs is not included in the standard package - which could mean that you would have to need buying a PSU separately (id est check first!) ..and that for a unit that appears to have ONE lousy PoE port! This all falls somewhat OUTside my own personal definition of 'good'. 
