Cisco 7940 and 7960 phones not supporting standard POE (802.3af)

Posted on 2006-04-11
Last Modified: 2008-01-09

I have purchased a standard POE switch which is compatible with the 802.3af protocol, but isn't compatible with Cisco's proprietary POE protocol, so my 7960G and 7940G phones don't work. Does anyone know of an adaptor I can purchase, preferably from the UK, so that I can use to get my POE CAT5E cable to power the Cisco POE phones?

Thanks a million

Question by:chrisbarr35
    LVL 36

    Accepted Solution

    The 'G' versions of the phones are 802.3af compatible so should work.
    If you have the old version of the phones then have a look at for some options on getting them working. It really depends what model of POE switch you purchased.

    Author Comment

    It does depend on the model of the POE switch. In the end I used a PowerDsine POE switch from which worked a treat with the Cisco adaptors provided.

    7940G and 7960G phones do NOT support 802.3af , but the new 7941 and 7961 ranges do.


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