Can anyone explain exactly what is Passive poe In and out?
In Polish but you can translate it:
It's a cheaper, non-standard variant of PoE that only works with compatible devices.
Unlike “proper” PoE, passive PoE can not automatically negotiate voltage.
To be picky (as I am) "voltage" is not actually negotiated in "active" (802.3af/at/bt) either, what is negotiated is the power class, voltage (and also Mode A vs. Mode B connection) is determined by the PSE and the PD has to accept it:
https://en.wikipedia.org/wiki/Power_over_Ethernet#Standard_implementation
I.e. a power supply at 48V will not "reduce" voltage to (say) 24 V, nor a power supply at 24V will raise voltrage to 48V.
Before any negotiation takes place (in active PoE out) or actual power is applied to the port (in passive PoE out) Mikrotik devices with PoE out make a check for resistance of the connected device:
- for passive PoE resistance should be from 3kΩ to 26.5kΩ
- for 802.3af/at/bt from 23.75kΩ to 26.25kΩ
I think he was actually asking about whether it was both in and out, not whether it was passive or not...
In/out, as the name suggests, can either passively supply voltage to power the device,
or (not simultaneously) supply voltage to power another device.
Obviously, in the latter case, voltage must be supplied either from another in/out port or from the power jack.
Ok, so my question actually has 2 parts relating to microtik routers that have passive poe ports (in/out)
- what is passive POE, i know what poe is jsut not what passive means.
- once that is answered what relevance/effect does the in port and out port do.
You can power a device that has PoE in from ethernet (if you provide the power by means of an injector and a power supply or from another device that has PoE out).
You can power another device from a device that has PoE out.
Some Mikrotik devices have both PoE in and PoE out, i.e. they can be powered by PoE in and power (usually only one) another device via their PoE out port.
Some Mikrotik device have either PoE in or PoE out, i.e. they have PoE out only if they are NOT powered through the PoE in connection.
that did not clear up anything for me.
if i have a POE injector what benefit is it that i plug it in the (IN) port on the router?
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Maybe no benefit.
You haven't even specified what the router is or what the PoE injector is. They may not even be compatible.
If you inject in that injector appropriate power (via the DC jack or by inserting the AC plug in a mains socket, for injector that integrate a power supply), that power will be injected on the ethernet cable (guess why It Is called Power over Ethernet).
Now if you plug the cable in a device PoE port in the device will be powered by that ethernet cable.
I am failing to understand what your doubts are, maybe if you would read or re-read the Wikipedia article:
https://en.wikipedia.org/wiki/Power_over_Ethernet
you can understand the basic concepts.
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i guess i’ll have to look elsewhere for the answer
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The quality of the answers often follows the quality of the questions...
Compared to what? Where to plug in?
If PoE injector is used to power the device to turn it on by ethernet cable,
what's the point of this question? I'm assuming you don't even know what PoE injector is at this point...
or that you put it in wrong... port...
Yep, but maybe Claude or ChatGPT can answer those questions directly or point to another place with more adequate answers. 
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Not true, also just because you say it doesnt make it true. My question was very simple to read and understand, however people just didn’t answer it, they answered stuff i did not ask for.
Questions do not have “quality”
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In short, they're all stupid and don't understand you...
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That must be the reason why people that attempt to provide answers on a forum have such a low pay and will soon be completely replaced by AI.
There's little to say, he gave the OK to the fact that we're all stupid...
You know, in a world of stupid, stupidity is normal, and it's the smart ones who are crazy...
Se la canta e se la suona...
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