8851 with KEM

[erodriguez@iqteksolutions.com]

Hi,

I have a site that recently changed their switches to Fortinet 424E-FPOE 421w, but now their 8851 KEM's are not working. My question is, what is the power needed of the 8851 with a KEM installed. 

Thanks

[Roger Kallberg]

Simple search with your favorite search engine would have given you the answer.

Power Requirements

• 8851 + (1) KEM – 8851 must be powered via 802.3af PoE, 802.3at PoE, or Cisco Power Cube 4.
• 8851 + (2) KEM – 8851 must be powered via Cisco Power Cube 4.

[Roger Kallberg]

Additional information Cisco IP Phone 8851/61 Key Expansion Module 

[erodriguez@iqteksolutions.com]

Rodger Thanks,

I see that the 8851 consumes 6.4w in idle state and 12.2w in active, but would happen to know the KEM's? I ask because the Fortiswitch is 421w and per port is 17.5w

[Roger Kallberg · Accepted solution]

The two supported PoE standards for the KEM is 802.3af and 802.3at. 802.3at gives maximum power to 25.5 watts and 802.3af gives maximum of 15.4 watts. 802.3at vs 802.3af: Which PoE Standard to Use Based on that the power that your Fortinet switch gives should be with the accepted range. I haven't been able to find any specific figures for what the KEM uses in idle or active state and I don't know that by heart either. Hopefully someone else in the Community can pitch in with this.

[erodriguez@iqteksolutions.com]

Thanks again!