How many Wireless Access Points can I plug into a Cisco Switch

I have a 4510 and want to plug some  air-lap1142n-a-k9 Access points and use POE. How many can I plug in with the current power availability?

4510#show power available
Power Summary                      Maximum
 (in Watts)              Used     Available
----------------------   ----     ---------
System Power (12V)        760        1360
Inline Power (-50V)        17        1300
Backplane Power (3.3V)     40          40
----------------------   ----     ---------
Total                     817 (not to exceed Total Maximum Available = 2100)

Powering Options
 • 802.3af Ethernet Switch
• Cisco AP1140 Power Injectors (AIR-PWRINJ4=)
• Cisco AP1140 Local Power Supply (AIR-PWR-B=)
Power Draw
 • AP1140: 12.95 W
Note: When deployed using PoE, the power drawn from the power sourcing equipment will be higher by some amount dependent on the length of the interconnecting cable. This additional power may be as high as 2.45W, bringing the total system power draw (access point + cabling) to 15.4W.

1300 watts available divided by 15.4 watts equals 84.4 APs?

Or should I consider the total maximum power?
Who is Participating?
SouljaConnect With a Mentor Commented:
I believe you are correct and should go by the inline power available.
lewisgConnect With a Mentor Commented:
Since the APs run on inline power then 84 is the correct number.

The more interesting issue is how you could deploy anywhere near 84 APs within the allowable cable length from the switch. My feeling is the wattage available for other devices, such as VoIP, instead of running a large number of APs.
SouljaConnect With a Mentor Commented:
I agree lewisg. I assumed the author was not going to actually deploy this, but just asking, because there is absolutely no way I could think of a scenario of deploying that many ap's to once switch.
Dragon0x40Author Commented:
We are initially deploying 11 on each switch and possible a few more later as necessary.

Sounds like the same math could be used for deploying voip phones as well.
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