You cannot pass PoE through a non-PoE switch; to power devices connected to a non-PoE switch, you need a PoE injector or a PoE splitter.

Key Considerations

PoE (Power over Ethernet) allows network cables to carry both data and electrical power to compatible devices. However, non-PoE switches cannot transmit power, only data. This means that if a PoE-enabled device is connected through a non-PoE switch, it will not receive power unless an additional device injects it along the path .

Methods to Provide PoE

1. PoE Injector (Midspan Device)
   • A PoE injector adds power to the Ethernet cable between a non-PoE switch and the powered device.
   • It has three ports: one for data input from the switch, one for power input, and one for PoE output to the device.
   • This is ideal for powering devices in locations where the switch cannot provide PoE directly .
2. PoE Splitter
   • A PoE splitter works in reverse: it takes a PoE signal from a PoE switch or injector and separates it into data and a lower-voltage power output suitable for non-PoE devices.
   • This is useful if you have a PoE source but need to power a device that cannot accept PoE directly .
3. Direct PoE Switch Replacement
   • If multiple devices require PoE, replacing the non-PoE switch with a PoE-capable switch is often the simplest solution.
   • This ensures that all connected devices receive power without additional injectors or splitters .

Important Notes

• PoE cannot be daisy-chained through non-PoE switches. The last switch before the device must be PoE-enabled to supply power .
• Active PoE switches detect whether a device is PoE-compatible before sending power, preventing damage to non-PoE devices. Avoid using passive PoE, which continuously sends voltage and can harm non-PoE equipment .
• Ensure that any PoE injector or splitter complies with the IEEE 802.3af/at/bt standards to match the power requirements of your devices . By using a PoE injector or splitter, or upgrading to a PoE switch, you can safely provide power to devices connected to a non-PoE switch without running separate AC power lines.