Baluns are more easily understood as a way to make BNC cameras compatible for use with Cat5e/Cat6 cable. The benefit of using Cat5e/Cat6 cable is it's noticeably cheaper cost, and ability to significantly stretch out the maximum length of your runs. With multiple types of video baluns in existence, you'll want to closely look at the purpose of each and determine which is most appropriate for you situation.
A video balun will send video from a security camera that has a BNC connector back to the DVR, but will not provide power to the camera. You still need to run an additional 2-lead power cable or use an individual power adaptor at the site of the camera. The maximum length of video transmission varies depending on the signal type of the BNC camera. For older analog cameras it is 1000 feet, and for HD security cameras over coax it is 800ft.
Another and much more popular option is a video power balun. Like the name implies, it will send video back to your DVR while providing power to the camera through the same length of Cat5e. These baluns will require you to crimp an RJ45 connector (shown in the video below) to both ends of your cable run. Like the video balun, the maximum length of transmission through Cat5e cable depends on the resolution and signal type of the BNC camera.
Pan Tilt Zoom (PTZ) Balun
The Video Power and Data Balun is specifically for use with Pan Tilt Zoom (PTZ) cameras that require a RS485 data connection with the DVR. Like the video/power baluns, they’ll require that you crimp RJ45 connectors to both ends of your Cat5e cable. The difference is that there will be an extra connection on these baluns to connect the RS485 data connection on the PTZ camera and on the back of your DVR. Without this, you wouldn’t have any control over an analog PTZ camera, negating it’s purpose. Just like our two previous options, maximum distance varies on camera signal type and resolution.
However as a rule of thumb, since PTZ cameras consume a lot of power we do not recommend powering them over a CAT5e or CAT6 cable over 100ft.
Passive Balun Transceiver
This is where things get a little more interesting. A passive balun transceiver works similarly to the previous three options, but with units like these, you'll be able to consolidate the number of video baluns needed.
Using a single passive transceiver and a video balun for each camera, you can have a streamlined installation without multiple small baluns hanging on the back of the DVR. You can have runs up to 800 feet for HDCVI cameras at 1080P resolution. Keep in mind that, like the video balun, you'll need to find another way to get power to your camera.
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