How many Devices can a PoE Ethernet Switch Connect to?

Nowadays, with the continuous development of network, the demand for equipment application is also increasing. An PoE Ethernet switch used in enterprise networks may need to connect IP cameras or Wifi access points and other devices, which requires the continuous upgrading of POE switches. Nowadays, POE switches have been developed to support two transmission standards, IEEE 802.3af and 802.3at, and their applications are more extensive. However, the number of ports and the maximum transmission power should still be considered in the selection of PoE Ethernet switches. Because a cable carries out power and data transmission at the same time, whether the number of ports and the maximum transmission power of a POE switch can support the corresponding number of devices needs to be calculated in advance.

At present, the most popular switch in the market is the PoE Ethernet switch with rated power of 150 W and 400 W. Taking the FS 8 port 150W PoE Ethernet switch and the 24 port 400W PoE Ethernet switch as examples, this paper further explains how many devices can be connected by a PoE Ethernet switch.

How many devices can a 1-port and 8-port PoE Ethernet switch connect to?
FS S1150-8T2F switch is a managed PoE + switch.
It has eight 10/100/1000 Base-T RJ45 ports and two Gigabit SFP ports, which conform to PoE standard IEEE802.3af/at, with a maximum power of 150 W and a maximum power of 30 W per port. Under the standard of IE802.3af, 8 (15.4W * 8 = 123.2W < 150W) devices can be connected at the same time. Under the standard of IE802.3at, 5 (30W x 5 = 150W) devices can be connected simultaneously. For example, if an outdoor IP camera requires 20W power from a PoE Ethernet switch, the connection of seven IP cameras will require 140 W (7 *20W) power.
How many devices can a 2-24 port PoE Ethernet switch connect to?
FS S1400-24T4F managed PoE + switch has 24 Gigabit PoE + ports, one console port and four Gigabit SFP ports. The switch meets the standard of IE802.3af/at with a maximum power consumption of 400 W and a maximum power of 30 W per port. Through calculation, we know that under the standard of 802.3af, 24-port switches can connect 24 (15.4W * 24 = 369.6W < 400W) switches at the same time, and 13 (30W * 13 = 390W < 400W) devices can be connected at the same time under the standard of 802.3at. For example, if an outdoor IP camera requires 20W power, then our 24-port PoE Ethernet switch can support 20 (20 x 20W = 400W) cameras.