Difference between Cisco Catalyst 48-port full PoE and Cisco Catalyst 48-port UPOE models

[apereira3]

Hello guys,

The information below can be found at the page 21 of the "Catalyst 3850 Switch Hardware Installation Guide":

"Depending on the installed power supply modules, each port can deliver up to 60 W of Cisco UPOE. See the Power Supply Modules, on page 26 for the power supply matrix that defines the available PoE, PoE+, and Cisco UPOE power per port. The output of the PoE+ circuit has been evaluated as a Limited Power Source (LPS) per IEC 60950-1."

I have a issue with two switch models of the Cisco Catalyst 3850 platform. The Cisco Catalyst 48-port full PoE model (Part-Number WS-C3850-48F) and the Cisco Catalyst 48-port UPOE model (Part-Number WS-C3850-48U) receive the default 1100W power supply. I understood that the two models has the same PoE per port capacibility, which means what the ports of two models can deliver up to 60W of Cisco UPoE.

So, what is the difference to the two models? The two models have the same configuration of the power supply, them why exists the two models?

Thank you very much!

Allyson

[Reza Sharifi]

Hi,

The document maybe misleading but WS-C3850-48F-L is POE+ (30 Watts max per port) and WS-C3850-48U-L is UPOE (60 Watts max per port).

HTH

[apereira3]

Hello Reza,

But, looking for the same guide (Catalyst 3850 Hardware Installation Guide), this document shows the table:

Models	Default Power Supply	Available PoE
48-port full PoE+ switch	PWR-C1-1100WAC	800 W
24-port Cisco UPOE switch
48-port Cisco UPOE switch

The power supply of the two chassis model allow the use of up to 800 W PoE power and repeating the text above:

"Depending on the installed power supply modules, each port can deliver up to 60 W of Cisco UPOE."

So, my questions:

- The WS-C3850-48F-L model can deliver up to the limit of 60W per port?

- Or the full PoE+ and UPOE model have differente hardware architecture that can be allow or no the reach of 60W Cisco PoE, independent of power supply availability?

Thank for your attention!

Allyson 

[Reza Sharifi · Accepted solution]

Hi Allyson,

Looking at an output from a non U 3850 switch with 2 1100W PSUs, the max is 30W.

xxxx#sh power inline

Module   Available     Used     Remaining
          (Watts)     (Watts)    (Watts)
------   ---------   --------   ---------
1          1440.0        0.0      1440.0
Interface Admin  Oper       Power   Device              Class Max
                            (Watts)                            
--------- ------ ---------- ------- ------------------- ----- ----
Gi1/0/1   auto   off        0.0     n/a                 n/a   30.0
Gi1/0/2   auto   off        0.0     n/a                 n/a   30.0
Gi1/0/3   auto   off        0.0     n/a                 n/a   30.0
Gi1/0/4   auto   off        0.0     n/a                 n/a   30.0
Gi1/0/5   auto   off        0.0     n/a                 n/a   30.0
Gi1/0/6   auto   off        0.0     n/a                 n/a   30.0
Gi1/0/7   auto   off        0.0     n/a                 n/a   30.0

I don't have a U version to test, but I would think it should be up to 60W.

HTH

[apereira3]

Ok Reza,

Thank you very much for your explanation and output shared with me!

Allyson

[Reza Sharifi]

Glad to help Allyson and thanks for the rating!