MR18 PoE interface voltage

[RVilhelmsen]

Hi,

I know the MR18 has a 100/1000Base-T Ethernet (RJ45) with 48V DC 802.3af PoE ....

But what´s the reason the ethernet interface will not accept a PoE power of 24V DC? I guess, it is not using over 12V internal.

Regards

Robert

[Adam]

In that case wouldn't you be undervolting the device?  I'm pretty sure the standard is 48V DC 802.3af PoE but I'm far from an electrical expert.  What are you wanting to try to accomplish?

[RVilhelmsen]

the standard says 48v, but the device don´t use 48v. If you power the device with a power supply, it is receiving 12v, so 24v is enough. I guess it must have some sort of 48v/12v internal converter which converts to the actual needed voltages.

But maybe they have designed the eth interface so it will not power on unless it receives 48v no matter what. Maybe the internal "things" can only convert from 48v down to the needed voltage.

It´s because i have som passive midline PoE adaptors running 24vDC/1A i which, i could use.

[RVilhelmsen]

i figured it out. My poe adaptor is passive and use pin 4,5,7,8. The meraki ap use pin 1,2,3 and 6.

Operating Input Voltage Range, V

36

57

This is for active PoE so it will not accept 24V anyway