@James-B 

Hi,

Recently, it was connected to power but nothing else whilst I was doing some maintainance on the cameras for a period of about a day, and this is when it failed.

Some suggestions for you:

1. confirm whether the data transmission still works fine with the switch, if not, it may not be the PoE issue.

2. test or change the ethernet cable, ensure the cable is in good condition.

3. find another power supply, check whether the cameras can still be powered up properly first.

If the cameras can be powered up by other power supply but not by the SG1008PE, it could be the PoE issue.

4. connect a working CCTV camera or other PD which supports the same POE standard as the SG1008PE, test if it can be powered up.

there should be LED indicators on the switch, pay attention to the LED status on the switch when you connect with the PD.

Good Luck!

Thank you for your reply, but the switch does not power up at all. The fan does not start and the LED's do not illuminate so unfortunately I had to replace it. 

Thank you for your help anyway :)