With the continuous development of network, the application demand of devices also increases. A POE Ethernet switch used in enterprise network may be connected to multiple devices such as IP camera or Wi-Fi access point, which requires constant upgrading of POE switches. Today, the POE switch has evolved to support IEEE 802.3af and 802.3at, two transport standards, and is used more widely. However, the number of ports and the maximum transmitted power should still be considered in the selection of the POE Ethernet switch, since a single cable is transmitting power and data at the same time, the number of ports and the maximum transmitted power of a POE switch should be calculated in advance to support the corresponding number of devices. This article will take two POE Ethernet switches with different port Numbers as an example to illustrate how many devices can be connected at the maximum power of POE Ethernet switches in different transmission standard modes.
Power range of PoE Ethernet switch
Currently, power of PoE Ethernet switches conforms to the IEEE 802.3af and 802.3at standards. The original IEEE 802.3af required power per port of the PoE Ethernet switch to be up to 15.4w. Upgraded PoE Ethernet switches, also known as PoE + Ethernet switches, have an IEEE 802.3at standard of up to 30W of power per port and are also compatible with IEEE 802.3af. However, due to power consumption in the cable, the minimum power output of each port of the PoE Ethernet switch is 12.95w, and that of the PoE + Ethernet switch is 25.5w.
The key to a successful PoE installation is to ensure that the selected Ethernet-powered switch provides the power required for each device, and that the total power must be sufficient for all devices. In short, the total power of all connected devices must be controlled within the maximum power range of the PoE Ethernet switch.
How many devices can a PoE Ethernet switch connect to?
The most popular PoE Ethernet switches on the market today are rated at 150W and 400W. To further explain how many devices a PoE Ethernet switch can connect to, take port 8 150W PoE Ethernet switch and port 24 400W PoE Ethernet switch as examples.
1. The PoE Ethernet switch has 8 10/100/1000base-t RJ45 ports and 2 gigabit SFP ports, which conform to the PoE standard ieee802.3af/at, with a maximum power of 150W and a maximum power of 30W for each port. Under IEEE 802.3af standard, 8 (15.4w ×8 = 123.2w <150W) devices can be connected at the same time. Under IEEE 802.3at, 5 (30W×5 = 150W) devices can be connected simultaneously.
2. How many devices can the 24-port PoE Ethernet switch connect to? There are 24 gigabit PoE + ports, 1 console port and 4 gigabit SFP ports. The switch complies with the IEEE 802.3af/at standard, with maximum power consumption of 400W and up to 30W per port. Through calculation, we know that under IEEE 802.3af standard, the 24-port switch can simultaneously connect 24 (15.4w ×24 = 369.6w <400W) switches and 13 (30W×13 = 390W <400W) devices.
From the above, you should know the power importance of the PoE Ethernet switch. If you are connecting multiple devices to a PoE switch, you need to calculate the total power required for all devices, while ensuring that the PoE Ethernet switch can provide the required current. For more details, you can contact our sales staff for consultation.
