Choosing Cable for Security Cameras: Coax, Ethernet, Power, and Fiber

Camera cable has to carry the right signal, deliver adequate power where required, and survive the installation environment. Choosing it only by price or appearance can produce intermittent video, nighttime power failures, or a costly replacement after the cable has been concealed.

Begin with the system type. Analog video commonly uses coaxial cable, IP cameras commonly use Ethernet cabling, and some installations combine a video cable with separate power conductors. Fiber can solve longer-distance and electrical-isolation problems, but the camera still needs a power source at its end.

Coaxial cable for analog video

A coaxial cable contains a center conductor, dielectric insulation, an outer conductive shield, and a protective jacket. For conventional analog CCTV and many HD analog systems, the intended video path is 75 ohms. Cable, connectors, and equipment should match the signal requirements.

RG-59, RG-6, and RG-11 are familiar 75-ohm families, but the label alone does not specify every construction detail or supported camera distance. Check attenuation at the relevant frequencies, conductor material, shielding, and the equipment manufacturer's distance guidance. HD analog formats can have different limits from standard-definition video.

RG-58 is generally a 50-ohm cable family and is not an interchangeable substitute for a specified 75-ohm CCTV cable. Likewise, RG-11 does not inherently include a supporting messenger wire. If an aerial span requires a messenger-supported construction, order and install a cable specifically designed for that use.

A 305-meter or 1,000-foot box describes the amount of cable supplied, not a guaranteed operating distance for one camera link. Rules assigning fixed maximum distances to every RG-59, RG-6, or RG-11 product overlook differences in the cable and signal.

Conductor, shield, and jacket quality

Solid copper, copper-clad steel, and copper-clad aluminum are different materials with different resistance characteristics. A construction suitable for one radio-frequency application may be unsuitable for carrying camera power or for a particular video transmitter. Follow the cable and equipment specifications rather than judging only the copper-colored surface.

Foil and braid provide different forms of shielding coverage. Their construction, continuity, and termination matter more than a vague claim that the cable is shielded. Poor connectors, damaged dielectric, water ingress, or a crushed cable can undermine otherwise suitable materials.

The jacket must match temperature, sunlight, moisture, mechanical exposure, and the route through the building. Respect the manufacturer's bend radius and pulling-tension limits; a universal instruction such as bending every cable to five times its diameter is not a substitute for the product's data sheet.

Twisted-pair Ethernet cable for IP cameras

Typical camera Ethernet cabling uses four twisted pairs. Twisting helps control interference and crosstalk. The cable category, conductor construction, connectors, and installation quality determine whether the completed link meets its intended performance.

Common shielding descriptions identify what is shielded. U/UTP has no overall shield and unshielded pairs. F/UTP adds an overall foil shield around unshielded pairs. S/FTP combines an overall braid with individually foil-shielded pairs. These descriptions refer to pairs and the cable assembly, not a separate shield around every individual conductor.

Shielding is not immunity from interference and does not authorize careless routing alongside power conductors. A shielded installation needs compatible termination and the appropriate bonding arrangement. Follow the equipment documentation and the requirements applicable to the actual route.

For PoE, use suitable standards-compliant copper cabling and verify the delivered power budget. Fluke Networks explains the problems with copper-clad aluminum cabling, including higher resistance, heating, and reduced voltage at the powered device. An inexpensive cable advertised with a category label is not proof of compliant construction.

How far can Ethernet run?

A conventional balanced-copper Ethernet channel is commonly limited to 100 meters, about 328 feet, including patch cords. A typical permanent link is limited to 90 meters, about 295 feet, leaving allowance for connections and patching. Fluke Networks distinguishes those channel and permanent-link limits.

Some camera switches offer proprietary extended-distance modes, often with speed or power tradeoffs. Treat those as specific equipment capabilities, not a change to every Ethernet link. Verify the supported cable, data rate, power load, and number of intermediate devices.

For longer routes, consider an appropriately designed fiber link, a supported extender arrangement, or a network switch at a suitable powered location. Each added device introduces power, environmental, and maintenance requirements. Fiber itself does not deliver electrical power to the camera.

Combined video and power cable

Siamese cable places a video cable and power conductors together for easier routing. It can be convenient for analog cameras, but the power conductors still have resistance. Their gauge, length, temperature, and current determine how much voltage reaches the camera.

The original suggestion that voltage drop over a long run is negligible is incorrect. For a simple DC circuit, voltage drop = current × total loop resistance. The loop includes the outgoing and return conductors. If a 12 V supply feeds a 0.5 A load through a 10-ohm loop, the drop is 5 V, leaving only about 7 V at the load in this simplified example.

Use the camera's peak demand, including infrared LEDs, heaters, or PTZ movement. A system that works in daylight can fail when those loads activate. A separate power cable does not automatically solve the problem unless its construction or power arrangement reduces the relevant loss.

Possible solutions include appropriately sized conductors, a suitable local power source, or a supported higher-voltage distribution arrangement with the correct conversion equipment. Do not apply an arbitrary higher voltage to a camera. Match the manufacturer's input rating and polarity.

Power over coax is another option only when the camera, recorder or injector, and cable are designed for the same supported system. It is not a reason to connect a generic power supply directly to a video connector.

Indoor and outdoor installation in the United States

Cable fire and environmental ratings must suit the installation. UL describes communications cable categories including CMP for plenum applications, CMR for riser applications, and CM for general-purpose uses. These markings are not interchangeable descriptions of all indoor cable, and none means the product is fireproof.

Sunlight resistance, wet-location suitability, and direct-burial suitability are separate considerations. Do not assume that a dark jacket or an outdoor marketing label establishes every one of them. The UL wire and cable guide explains marking and use distinctions.

Have the installer confirm the applicable local requirements, listing, route, and building-entry treatment with the authority having jurisdiction where needed. A foreign cable classification should not simply be relabeled as a U.S. rating.

Outside, protect connectors from moisture and provide the required strain relief and supports. An aerial cable needs a design suited to the span and loading. Between buildings, fiber can help avoid a conductive data path, although power, metallic cable components, and protection details still require proper design.

Compare installed cost, not just price per foot

Old regional price lists cannot provide a reliable current U.S. budget. Obtain quotations for the complete installed link, including labor, connectors, testing, and warranty. Label both ends and document the route so future repairs do not begin with guesswork.

Match the cabling design to the selected security cameras and recording equipment, then test video and power under the most demanding expected operating conditions.