All I meant to say was that you should understand a little bit about the switch you intend to purchase, and the devices you want to connect. For example, I just bought a Netgear GS308P switch. It has a total of 8 ports, but only 4 of them are PoE. Now if I had say 4 devices that required 15W each for a total of 60W, I could only connect three of them. That is because even though the PoE ports will supply 15.4W per port as per the 802.3af standard, the power budget for the switch is only 53W. So if you wanted to connect all four of the devices to one switch, your options would be to purchase a different switch with more PoE ports (because the power budget would MOST LIKELY be higher), or a switch with the same number of ports but conforms to 802.3at standard that supplies 25.5W per port.
There are other things that need to be considered too. For example, if the four devices were PTZ cameras that had a MAX power consumption of 15W, you MIGHT still be able to connect all four to the GS308P even though the MAX requirements exceed the power budget available. That is because the max power consumption for a PTZ occurs when all of the P, T, and Z motors are running simultaneously. So if the cameras are all manually controlled, it is unlikely that you would exceed the power budget but this is still not a good idea. If they are programmed to continuously scan an area and are constantly using max power, your little switch is gonna burn in hell. Actually what SHOULD most likely happen is that one port would turn off the power.
Wayne
