PoE of 802.3af switches

802.3af

— switches that only support the PoE 802.3af standard.

This is the oldest active PoE power format in use today, with relatively modest capabilities. Provides power at the power output up to 15 W (at the input of the consumer — up to 13 W), output voltage 44 – 57 V (at the input — 37 – 57 V) and current in a pair of supply wires up to 350 mA. And although this is quite enough for many models of network equipment (and the implementation of PoE 802.3af is cheaper than more advanced formats), this standard is rarely used in modern switches as the only one. Most often it is an addition to the newer and more advanced 802.3af or 802.3bt; devices with such capabilities are listed in the relevant paragraphs, and the features of specific standards are also described there. And you should pay attention to this option first of all if you need a relatively inexpensive solution that you plan to use with outdated or modest in terms of power consumption PoE devices that also use 802.3af. Note that this standard immediately covers 4 power classes (from 0 to 3), which differ in the maximum number of watts at the output and input. So when using this power format, it's ok to make sure that the output power will be sufficient for the selected load.