Video surveillance cable isn't always the right length when installing or relocating a system. In cases like this, the cable needs to be extended. Let's look at how to do this correctly, and what the maximum cable lengths are.

Optimal Cable Length for High-Quality Video Signal Transmission

Cable length depends on its type and the data transmission method. For example:

Cable Type Model Optimal Distance Comments
Coaxial RG6 400 meters If the distance exceeds the optimal value, the image will lose sharpness
RG59, RK, KVK, 3C-2V 200 meters  
Twisted Pair With an active transceiver on both ends 100 meters As the distance increases, banding will appear in the image and interference will become more noticeable.
With a passive transceiver 200 meters If the distance exceeds the optimal value, the image will lose sharpness
Without a transceiver 150 meters As the distance increases, sharpness decreases

But how do you extend a coaxial cable or twisted pair cable if the optimal length isn't enough?

Extending Coaxial Cable

Coaxial cable for video surveillance is durable, budget-friendly, and allows for longer cable runs than twisted pair. The cable consists of a central conductor and a braided shield — to extend it, follow these expert tips.

4 Expert Tips

The extension method depends on the type of central conductor the cable has: stranded or solid. Let's look at both options:

1. Solid-Core Cable

Screw an F-type coaxial connector onto the end of each cable, then join the two together with an F coupler.

Advantages of this method: it helps prevent signal loss, and the connections are resistant to mechanical damage.

2. Stranded Cable

Strip off the shielding and twist together the strands of the central conductor. Then dip the soldering iron tip in a neutral soldering flux and solder the joint. Connect the two cables the same way as with solid-core cable — using an F coupler and F connector.

Advantages of this method: the central conductor becomes more rigid.

Extending Twisted Pair Cable

Twisted pair cable only covers a fairly short distance, which is why it's extended most often in outdoor systems. To maintain data transmission quality, reduce noise, and increase signal range, special transceivers are used — the same ones mentioned in the table above.

3 Expert Tips

There are 3 ways to extend twisted pair cable:

  • •         Using special coupler/keystone modules. With this method, you crimp connectors onto both cable ends, then join the cables using the coupler module.
  • •         A UTP inline coupler/extender
  • •         Soldering — though this method is complex and time-consuming

It's also recommended that you avoid simple twisted splices, since the wire can oxidize over time.

In Lieu of a Conclusion

Cables can always be extended — the key is knowing the methods that preserve signal quality. That said, there are sites where running cable simply isn't possible. In those cases, it's worth considering Wi-Fi video surveillance.

And to avoid having to rebuild the entire system multiple times, it's worth developing a full surveillance system design early on, one that spells out every detail.