How To Fit CCTV Right
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How can I avoid cabling issues?
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Here's six tips for the best results
Cabling is almost always an afterthought.
People spend time choosing the best cameras and the best recorders, then give barely a moment's thought to the link between them.
That's a mistake. Many an installer has spent hours fault-finding on a new job - swapping out cameras, checking recorders - only to discover the equipment was fine all along.
The cable was the problem.
Most cabling problems are entirely avoidable. Here's how.
Keep Joins to a Minimum
Every time you terminate a cable, you create a potential failure point - now or in the future.
A bad crimp, a loose connection, signal loss. Any of these can cost you hours.
Plan your runs carefully and use a single cable from A to B wherever you possibly can.
Avoid Tight Bends
Tight loops and sharp bends cause more problems than most people realise.
With network cable - CAT5 or CAT6 - a tight bend can damage the inner cores without leaving any visible sign.
The result is an intermittent signal or no signal at all. You might have a perfect RJ45 crimp at both ends and still find the NVR can't see the camera.
Before you start replacing equipment, check whether a tight bend somewhere along the run is the real culprit.
With coax cable, tight bends affect impedance, cause high-frequency losses and can produce double images. Even expensive, high-quality coax will give you a poor picture if it's been bent sharply during installation.
The rule of thumb:
Keep bends to no less than 10 times the cable's diameter. A 6mm coax cable needs a bend radius of at least 60mm - which means a loop no tighter than 120mm across.
Terminate it Properly
Use the right tools. Proper cable strippers and a good crimp tool will save you a great deal of grief.
Trying to get away with the wrong tools risks short circuits from bad crimps and damage to the cable itself.
Don’t Overstretch
Always buy more cable than you think you need.
If you're forcing cable through conduit or roof voids, you're probably stretching it - and internal damage from stretching isn't visible until it shows up as a poor image or a lost signal.
Pull gently. If it won't go, find out why rather than forcing it.
Check Your Route First
Before you pull any cable, make sure the route is clear - particularly if you're going through underground ducting.
A set of flexible ducting rods will help you find the easiest path and put far less stress on the cable during installation.
Don't Skimp on Cable Quality
Saving a few pounds on a cheaper roll of cable is a false economy.
The time and cost of tracking down and fixing problems caused by poor cable will far outweigh whatever you saved.
For both network and coax cable, solid copper cores give the best results. Budget cables with Copper Coated Steel or Copper Coated Aluminium cores (CCS or CCA) conduct less efficiently and will cause signal loss - especially over longer runs.
Copper is the most conductive of all commercial metals - 65% more conductive than aluminium.
It also resists corrosion well and even when it does oxidise, the coating continues to conduct. It stays flexible across a wide temperature range and is straightforward to join and solder.
Solid copper costs a little more. But it's worth it.
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