What line should the camera used in the hotel wear and how big is the bobbin?

Every camera can be installed in a JDG tube. 20 will do. Follow it, maybe when it comes to three cameras, you can wear one? 25 pipeline, the closer to the computer room, the more lines will be, and trunking can be used.

Each camera has a video cable and a shielded dual-core power cord. If it is a tripod head, you need to shield the three-core wire.