POE on C4507 and C6509 switches

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Sep 12th, 2008
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I am now ordering the newer model IP phones, 7965, 7975, 7937. When I plug in these new phones they don't work on the c4507 or c6509, but they do work on the c3750. It seems that the new phones have a higher power rating and the older switches POE isn't enough to power the phones. What would be my resolution to fix this? Would I need to purchase new blades to go in these switches?

For example: I have a WS-X6148-RJ45V in the 6509 and all my other IP phones work fine. In the Cisco Global Catalog there is a WS-X6148A-RJ-45 and says it is upgradeable to PoE 802.3af. So it sounds like I do have to order new blades.

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Rob Huffman Sat, 09/13/2008 - 07:09
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Hi Kimble,

You are most correct my friend :) The newer IP Phone models that you listed (like the 7965) are Class 3 PoE devices which means that the require 15.4W of power. The blade that you are using like the WS-X6148-RJ45V will only provide PoE for Class 2 devices (like the 7961) which require only 7W of power.

There are a number of blades that would work shown in this good guide;


Hope this helps!



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