Using Cat5 (UTP) in CCTV installation vs RG59 Siamese Cable

Recently we have noticed that more and more CCTV installers use Cat5 cables for analog CCTV system installations. With Passive Video Baluns based on specification you can use UTP cable to transmit color video as far as 1300ft. With a active CCTV Balun you can go as far as 5000ft. While it is much more than with RG59 cable there are some issues you may run into while using Cat5 cable on long runs. First of all it is a power issue. With Cat5 cable you can use remaining 3 pairs for power. This is recommended for long runs of 500ft and more. With those distances, I would not use 12V DC. Due to the voltage drop you need to use 24V AC cameras. With more power consuming infrared cameras, you need to actually use AC power supply with a 28V output. Only this way you can compensate for a voltage drop at the end of the cable. Long range infrared cameras would need a power supply located much closer to the camera or need an extra cable to supply power at those distances. 3 Pairs of Cat5 cable will not be sufficient to provide enough power even with 28V power supply in case of Long Range Infrared Cameras. When using an active CCTV Balun, it is necessary to put power supply much closer to the camera. There is no way we can transmit the power at a distance of 5000ft using traditional methods.
Another thing about UTP installation is a higher resistance to interference of UTP Cable. We have some observations of our own regarding this issue. There are cases where coaxial cable may be useless. Installing cameras in close proximity to high powered TV or Radio antennas or even cell towers may result in complete lack of image on coaxial cable. This may happen even on a short runs of 200ft. Cat5 Cable usually performs much better in this type of environment. But where there is no significant electromagnetic field we observe coaxial cable to actually outperform Cat5 cables on runs of 500ft and more. In both cases video has very decent quality, but Cat5 cable tends to produce lines and sometimes little ghosting effect while RG59 picture is more stable.
So there is no one perfect solution. Choice of the cable should be based on few other factors other than just installer’s own preference. We like using RG59 Siamese cables on most of the installations where cameras are located not farther than 1000ft and there is no more than 32 cameras. On the other hand Cat5 cable is much easier to run and if you are using Conduit, Cat5 cable will be a great money saver. Cable management at the base is also an issue with a UTP cable. There is just no way to make it look perfectly clean. Thus we really do recommend using dedicated cabinet or a server rack when dealing with Cat5 cable. If you put DVR on the desk and have all those baluns and wires hanging there, you will be back there many times with a service call. Something to keep in mind.