PoE possible on all 48 ports?

[AlexJohansson]

Hello community,

In my company we use a few HP 5130-48G-4SFP+ switches to where we connect all office computers and WiFi access points. All APs are connected through PoE and draws 13W each at most. I did some calculations and I think we're well within the capabitlity margins for what a switch could handle. No switch has more than 15 APs anyway.

But I just want your support to confirm a good setup. Some experienced colleagues say the switches can't handle more than 5-10 APs through PoE.

[sdide]

Hi,

that depends. Which HP 5130-48G-4SFP+ are we talking about? Is it the

"HPE 5130-48G-POE+-4SFP+ EI (JG934A)"

or the

"HPE 5130-48G-POE+ 4SFP+ HI (JH324A)"

because there is quite a difference.

Anyways I'm guessing the former, the EI model. That one has a 370W PoE budget. So an equal distribution of Power pr port gives 370/48  = 7.7 Watts pr port.
or if you talk full PoE+ (which is rated to 30W), you have enough power for 370/30 = 12 ports maximum.
Normal PoE rating is 15.4Watts which gives 24 ports.
You can tell your power-budget in detail by issuing the command.
] display poe pse

Here is an example from one of our switches running 3113P05 (shipped software)

<MY_UNIT>display device
Slot Type                 State    Subslot  Soft Ver             Patch Ver
1    5130-48G-PoE+-4SFP+  Master   0        3113P05              None
     EI
<MY_UNIT>display poe pse
 PSE ID                           : 4
 Slot No.                         : 1
 SSlot No.                        : 0
 PSE Model                        : LSP7POEB
 PSE Status                       : Enabled
 Power Priority                   : Low
 Current Power                    : 104.7    W
 Average Power                    : 105.2    W
 Peak Power                       : 115.1    W
 Max Power                        : 370.0    W
 Remaining Guaranteed Power       : 370.0    W
 PSE CPLD Version                 : -
 PSE Software Version             : 146
 PSE Hardware Version             : 57633
 Legacy PD Detection              : Disabled
 Power Utilization Threshold      : 80
 PD Power Policy                  : Disabled
 PD Disconnect-Detection Mode     : DC
<MY_UNIT>

So, if your maximum usage is 15 APs at 13Watts, you should be well below the limit.

NB: If you do have the HI-model, the PoE budget is depending on which power supply units you are using.
it has a 720W option and a 1100W option (with 2 slots) which actually gives you the possibility for PoE+ on all 48 Ports.

Regards

[AlexJohansson]

Thank you Søren for your answer. I had a closer look at the switch in question last week, and it's the "EI"-version (model JG937A). Don't know how it differs from the JG934A you mentioned.

So with the 370W PoE-budget we're theoretically able to connect up to 28 of our APs to 1 switch. Practically, we don't need to worry at all.

I'm not at the site at moment, but will look at the power-budget when possible. Thank you for your help!

[sdide]

Hi, about the JG934A vs. JG937A

You're right, I must have copypasted from the wrong entry in the paranthesis. The JG937A is the PoE+ version with the 370W PoE budget, the JG934A is without PoE.

Thank you Søren for your answer. I had a closer look at the switch in question last week, and it's the "EI"-version (model JG937A). Don't know how it differs from the JG934A you mentioned

Regards