Community discussions

MUM Europe 2020
 
tyoma53
just joined
Topic Author
Posts: 8
Joined: Fri Mar 21, 2014 9:08 pm

mAP2n PoE for Yealink W52P

Sun Nov 11, 2018 9:26 am

Greetings all,

Can I power Yealink W52P phone DECT base station from mAP2n using mAP2n's standard 24V 0.8A power adapter and RBPOE injector for mAP2n's first ethernet port and second port to Yealink's base station?
According specs Yealink supports Power over Ethernet (IEEE 802.3af), Class 2 and requires C 5V/600mA input.

Thanks.
Last edited by tyoma53 on Sun Nov 11, 2018 11:47 am, edited 1 time in total.
 
nescafe2002
Long time Member
Long time Member
Posts: 645
Joined: Tue Aug 11, 2015 12:46 pm
Location: Netherlands

Re: mAP2n PoE for Yealink W52P

Sun Nov 11, 2018 11:18 am

No, not by specs, but you could try with a standard 802.3af injector (48V).

I have had success with the following setup: standard 802.3af switch (Netgear FS728TP) => mAP2nD => Yealink T46G desktop phone.
 
tyoma53
just joined
Topic Author
Posts: 8
Joined: Fri Mar 21, 2014 9:08 pm

Re: mAP2n PoE for Yealink W52P

Sun Nov 11, 2018 11:47 am

No, not by specs, but you could try with a standard 802.3af injector (48V).

I have had success with the following setup: standard 802.3af switch (Netgrea FS728TP) => mAP2nD => Yealink T46G desktop phone.
thank you.
could you please explain why should I need so powerful injector? e.g. I can power 2 mAP2ns, which POE-in supports 802.3af, from one RBPOE, but not mAP2n and Yealink 802.3af phone. according mAP2n specs its POE input voltage is standard for 802.3af - 12-57 V.
I tried to google it, but it's still confusing to me, why 802.3af POE-in of Mikrotik means it can be powered by passive POE-out of other Mikrotik, and 802.3af POE-in of other device means it can't be powered by passive POE-out.
 
mkx
Forum Guru
Forum Guru
Posts: 3565
Joined: Thu Mar 03, 2016 10:23 pm

Re: mAP2n PoE for Yealink W52P  [SOLVED]

Sun Nov 11, 2018 12:13 pm

IEEE (or which ever) standard for power over ethernet, called 802.3af, defines active negotiation between power "donor" and "receiver". One of typicalities (I'm not sure, might be part of standard itself) is voltage of 48V.

However, many vendors "invented" passive PoE which does not use any kind of handshake between both sides, but rather power donor provides power and receiver can take it. In this case voltage is not defined, nor are any other details. So mikrotik's passive PoE can take any voltage suitable for both devices.
Traditionally this kind of PoE used two pairs of ethernet wires that were not used for fast ethernet (100BaseTX).

Some mikrotiks support both proprirtary pasdive PoE out as well as standard 802.3af PoE out but that usually mandates 48V power supply necessary for 802.3af ... but which might be too high for some devices not supporting 802.3af which take up to 28V on input.
In addition to this, many mikrotik devices have (per PoE out port) current limitations which sometimes limits application possibilities.


In short: PoE on mikrotik is not a simple thing.
BR,
Metod

Who is online

Users browsing this forum: AlexL, Borismuh and 29 guests