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Xela
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hEX PoE lite - PoE operation

Thu Sep 14, 2023 6:53 pm

Hi
I purchased a hEX Poe Lite (RB750UPr2) to be used as a simple PoE switch.
In summary I wanted to power (with CAT 7 ethernet cable of about 40 m) the Hex via the Lan1 PoE and for it to power via the Lan2/5 (with CAT 7 ethernet cable of about 50 m) n. 4 Metal 52ac APs.
Unfortunately, I was not able to do this.
If I feed PoE to the hEX this does not feed the APs.
On the other hand, if I feed the hEX with its DC connector power supply then the Metal APs work perfectly with PoE.
Where did I misconfigure?
Thx
Alex
 
holvoetn
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Re: hEX PoE lite - PoE operation

Thu Sep 14, 2023 7:01 pm

Are you using standard POE as input ?
That's 48V, if I am not mistaking ?

Which means Hex will feed 48V as well to it's clients.
Netmetal AC52 can not accept that voltage, it needs 10-30V.

Standard power brick for Hex POE is 24V, within the range needed for Netmetal.
 
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Xela
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Re: hEX PoE lite - PoE operation

Thu Sep 14, 2023 7:06 pm

I use its 24V 2.5A power supply.
I have also tried 28V and 2.5A power supply but nothing changes
 
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Re: hEX PoE lite - PoE operation

Thu Sep 14, 2023 7:53 pm

Enable this setting and try but use it with precautions.
https://wiki.mikrotik.com/wiki/Manual:PoE-Out
/interface ethernet poe settings
set ether1-poe-in-long-cable=yes
 
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Ca6ko
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Re: hEX PoE lite - PoE operation  [SOLVED]

Fri Sep 15, 2023 9:28 am

Where did I misconfigure?
"A chain is only as strong as its weakest link."
You haven't calculated the budget of the POE.
The standard RG45 port is designed for a maximum current of 1A.
That is, when powered through the first port, the hex can consume a maximum of 24W when powered from 24V minus cable losses. 3W is needed by itself. That leaves 20W, the Metal 52ac consumes 11W. That is, with this scheme you can power a maximum of 1 AP.
If you power the hex directly from the power supply, it can deliver a maximum current of 2A to all 4 ports. which in your case means 12W per port. and this is enough.
PS
What to do? You can use two RBGPOEs (they support 2A) plugged into both ends of the cable. And power it from a 28V power supply. Connect the power output of the RBGPOE to the power input of the hex. With a male to male adapter
PSS RBGPOE is included in the Metal52ac kit.
 
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Xela
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Re: hEX PoE lite - PoE operation

Sat Sep 16, 2023 1:47 pm

Where did I misconfigure?
"A chain is only as strong as its weakest link."
You haven't calculated the budget of the POE.
The standard RG45 port is designed for a maximum current of 1A.
That is, when powered through the first port, the hex can consume a maximum of 24W when powered from 24V minus cable losses. 3W is needed by itself. That leaves 20W, the Metal 52ac consumes 11W. That is, with this scheme you can power a maximum of 1 AP.
If you power the hex directly from the power supply, it can deliver a maximum current of 2A to all 4 ports. which in your case means 12W per port. and this is enough.
PS
What to do? You can use two RBGPOEs (they support 2A) plugged into both ends of the cable. And power it from a 28V power supply. Connect the power output of the RBGPOE to the power input of the hex. With a male to male adapter
PSS RBGPOE is included in the Metal52ac kit.

Wow!
Thank you for the biggest explanation.
I will try what you suggested.
Many thanks

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