PoE supply voltage is not always 24V, the standard PoE supply voltage is usually 48V. Standard PoE devices comply with IEEE802.3af or 802.3at standards, which stipulate a supply voltage of 48V.
However, there are also non-standard PoE devices whose supply voltage can be 24V, 12V or even 5V.
Basic concepts and standards of PoE technology
Power over Ethernet is a technology that sends power through network cables. It provides power and data to IP devices without needing to change the current Ethernet wiring. Standard PoE devices must negotiate between the power supply and the power receiving device.
Application scenarios and safety considerations of different voltages
24V PoE: Usually used for certain specific devices because they may require lower voltage power supply.
12V PoE: Suitable for some low-power devices, such as some surveillance cameras.
5V PoE: Although less common, it is also used in some specific applications.
Safety considerations
When using non-standard PoE devices, you need to pay attention to the voltage requirements of the device. If the device's voltage needs do not match the PoE supply voltage, it can damage the device or reduce its performance. Therefore, when selecting PoE devices, you should ensure that their voltage requirements match the PoE supply voltage.
