Power over Ethernet is a pretty awesome technology – it allows you to power various electronic devices using only an Ethernet (CAT6/CAT7) cable. But is this safe? And what happens if you accidentally plug a powered Ethernet cable into a non-PoE device? Will it get damaged?
Well in 95% of cases, nothing bad will happen. That’s because GOOD PoE switches and injectors will safely negotiate with the end device, to determine whether to send power of not. This means that if a device does NOT support PoE, the switch will only send internet traffic – and not power as well.
But you should be careful of “passive PoE switches”, because these always send power. They can cause a burn out of your device or its RJ45 Ethernet port.
I demonstrate all this in a quick 1 minute short video:
You can also view this short on:
I discuss the “dos and don’ts” of PoE in another article if you wanted to learn more about this topic.