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I have a question regarding PoE technology.
I understand that PoE switches only supply power if it's requested by the device. My question is how can the device request power if it has no power? What actually happens between the switch and the device prior to the switch supplying power?
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The device does not have to actively request anything. It is identified as a PoE consumer by having a particular resistance present between two of the pins in the ethernet jack.
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to add insult to injury for op, there are two different nominal voltage values, most devices are either one or the other, so have fun experimenting :^)
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>>59760717
that's how nearly ALL electronic technologies work
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>>59760753
Perfect, thank you! As a followup, which pins would that resistance be present, and what's the resistance value?
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>>59761327
Depends on the PoE standard used. There are many of them and they often conflict.
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>>59761507
>conflict
Is that a nice way of saying "fried"?
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