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Can a WS-C2960X-48LPS-L power 48 phones?

I am trying to get some clarification on the WS-C2960X-48LPS-L, is it able to supply power to 48 phones? If Cisco's IPM is required for this to work, can this be done using LLDP instead of CDP?

Look at table 6 Intelligent Power over Ethernet Plus at http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-2960-x-series-switches/data_sheet_c78-728232.html it lists max number of ports for 30W and 15.4W devices but not 7W.

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Bronze

When Poe device detected,

When Poe device detected, switch will provide 15.4W then throttle back when low power device is detected.

If power supply can provide 740W PoE for 48*15.4W, then 48*7W will not be a problem.

New Member

The WS-C2960X-48LPS-L has a

The WS-C2960X-48LPS-L has a 370W power supply.

So what happens if the switch undergoes a cold boot with 48 phones connected to it? The phones I am looking at only draw 7W based off the power brick. The phones support IEEE 802.af Class 2 and LLDP-MED, they do not support CDP

.

Does the switch providing/allocating 15W per port become an issue?

 

New Member

I think i may have found the

I think i may have found the answer to my question at the document referenced below.

"The switch uses the IEEE classification to learn the maximum power consumption of a powered device before powering it. The switch grants power only when the maximum wattage configured on the port is less than or equal to the IEEE class maximum. This ensures that the switch power budget is not oversubscribed. There is no such mechanism in Cisco prestandard powered devices. "

Am i correct in reading this as the switch can autosense the phone is a Class 2 7W device even before powering up the phones (regardless of cdp/lldp) so a switch with a 370W power supply can cold boot and power up 48 7W phones?

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960/software/release/12-2_44_se/configuration/note/ol14988.html

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