Wireless Access

Hi Friends,

I am not sure if its not the proper forum to ask this question but it seems most appropriate to me.. So appologise in advance if i m wrong.

well my question is I have installed 23 AP-92 with single PoE switch. Now as per datasheet of AP-92 it consumes 10watt while the switch i installed mentioned in its data sheet that it can support maximum 180 watt power on PoE. So here the confusing part, as per datasheets of switches and AP's 180/10 = 18, mean that only 18 AP's would be power up and running but in my case all of 23 AP's are up and running. What I concluded is " Either AP is using less power than 10W or Switch is providing more than 180W" .

What do you say about it ??

A couple of comments:

- The latest AP-9x datasheet mentions 8W as the maximum (worst-case) power conumption when powered from POE

- In typical operation, the AP-9x will consume significantly less, especially when considering the average power consumption of multiple devices. 6W per AP is probably a safe number

- When using POE, some additional power will be consumed (lost) by cable resistance, so the power draw from the POE source will be a bit higher. This depends on cable type & length, supply voltage and current needed to supply power to the AP. At 6W AP consumption, and assuming CAT5 cable and max length, this adds just 0.25W though.

I would think that if 180W is available, it should be enough to power up to 30 AP-93 units.

Thanks,

/Onno

Just to add more relevant info regarding the previous post:

AP-93 = 802.3af  = MAX 12.95watts

The current delivered to each node is limited to 350 milliamps. The total amount of continuous power that can be delivered to each node, taking into account some power loss over the cable run, is 12.95 watts. IP phones and wireless LAN access points typically consume 3.5 to 10 watts.

12.95W is indeed the guaranteed minimum amount of power available to an 802.3af POE device (assuming worst-case conditions, cable loss etc.). The AP-93 consumes significantly less, see my earlier post.

/Onno