How to Use Fiber-Optic Cable for CCTVby Frank Gates
Closed-circuit TV (CCTV) systems use coaxial cable, wireless technology and fiber-optic cable to transport the cameras' signals to the monitor. Fiber-optic cable is a good choice when there is a high likelihood of off-air interference such as power lines or nearby Radio Frequency (RF) transmitters. Fiber-optic cable is also the solution for very long CCTV transmission links of more than 300 feet. Fiber-optic cable also can improve reliability and reduce maintenance costs. CCTV cameras and monitors are typically looking for RF signals, so in order to use fiber-optic (light frequency) signals, your CCTV system must have fiber-optic cable and connectors, a fiber-optic transmitter and a matching receiver. The transmitter and receiver also converts the normal RF signals to light frequency signals to give your camera and monitor the signals they need to operate.
Place the fiber-optic cable between the camera and your monitor. Multimode 2-strand fiber optic cable will be the most economical for a single camera installation. One strand will be used to carry the optical signals while the second strand will remain dormant and can be used as a backup in case the first strand should break. This camera/monitor link should not have any splices in the link.
Place one ST (straight tip) male fiber connector on each end of the fiber cable after the fiber cable is in place. Make sure to leave 18 inches of slack (coiled) at each end to accommodate equipment placement.
Place the FO transmitter at the camera location end of the fiber cable and the FO receiver at the monitor location end of the fiber cable. Neither of these devices is designed for outside use and must be protected from the elements. The transmitter at the camera location does not need to be next to the outdoor camera and can be located inside the building using the coaxial cable output between the camera and the transmitter to provide 10 to 20 feet of placement flexibility. The FO receiver located at the monitor is typically inside the structure. Remember that both the FO transmitter and the FO receiver will need available 110 VAC power outlets for the power supplies that power each of these devices.
Connect the FO transmitter to the camera using the pre-made coaxial cable jumper. You can also make your own coaxial jumper from a cut length of coaxial cable by adding two BNC (Bayonet Neill-Concelman) connectors, one at each end of this jumper.
Connect the external power supply to the FO transmitter.
Connect the FO receiver to the monitoring device using a coaxial cable jumper. This monitoring device can be a digital video recorder (DVR) or a video card in a computer. DVRs or video cards are typically configured with BNC connectors.
Connect the external power supply to the FO receiver.
Test this completed fiber-optic circuit to ensure your camera and monitor are functioning properly and the link is complete.
Items you will need
- Fiber-optic (FO) cable, 2-strand, multimode (footage as required)
- ST (straight tip) male Corning fiber-optic connectors (2 each for each FO link)
- Connector placement tools
- FO transmitter
- FO receiver
- Coaxial cable pre-made jumpers or cut lengths of coaxial cable, 2 each
- Coaxial cable BNC connectors for cut lengths, 4 each
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