Multi-port PoE injectors are a nice option to add say 3-8 PoE ports to an existing switch. More flexible in some ways, I’m using 1 port of my 8-way injector to

Multi-port PoE injectors are a nice option to add say 3-8 PoE ports to an existing switch. More flexible in some ways, I’m using 1 port of my 8-way injector to add PoE to the WAN interface of my router. In conjunction with an active PoE “splitter” on the far end I can remotely power the GPON modem on the other side of the house and power everything from one UPS. I also made sure to get a Mode A “gigabit” injector in order to power 2x PoE cameras in a location with a single Cat6 drop. On the far end there’s just a passive splitter, each camera only gets 2 pairs which run both 100Mbit Ethernet and PoE. Cheaper “non-gigabit” PoE Mode B injectors save a buck by omitting the isolation transformers and instead inject DC onto the spare pairs, so not compatible with pair scavenging. MikroTik’s PoE switches also use Mode B. They’re gigabit so have to include the isolation transformers anyway, presumably this is due to their ability to operate in 24V passive PoE mode. I was going to get a MikroTik switch but my pair scavenging requirements drove me down the path of a separate multi-port injector, which worked out to be a lot cheaper too! 8 port injector with a decently powerful 56V power supply was approx $100 via AliExpress. Only drawback is a bit more cabling and no ability to remote power cycle an individual port.