Why CAT5?

[SamG269]

I am seeing this cable mentioned everywhere. Especially when it comes to new installs and upgrades where wires are being ran. My question is why is CAT5 a cable that should be ran? What are the different applications with using this cable? I know what the cable is.

[Mustangnaz]

I think the main reason is the cost per cable (4 pair in CAT5). Obviously there are a lot of network uses such as connecting computers, servers, copiers, NAS, and TVs. You can also use converters to inexpensively run video over CAT5. My installer also runs CAT5 for phone because it's just about as cheap and give you future flexibility with more pairs. And my newest use for CAT5 is for computer controlled Christmas lights.

[bggowing]

The other big reason for Cat5 is the allowance for significantly longer runs of cable compared to other cable. Also instead of having to run different specialty cables all over the place you can just run CAT5 and use different adapters as required for your needs.

FYI Cat5 is being phased out. If you're putting new stuff in the minimum you should use is Cat5e or Cat6.

[SamG269]

So when it comes to sound theres not much needs?

Im curious as to the different uses that it has. You mentioned network for computers, etc. But what else? What are some examples?

[tedanderson]

Typically people are running Cat 5 cable because it's cheap and ubiquitous. When you are doing an install and you aren't quite sure what equipment/connections will be required, then Cat 5 is sort of a catch-all infrastructure. Granted I prefer to run coax, VGA, HDMI and other types of cable where I KNOW that I'll need it but the Cat 5 can always get you through a last-minute change.

When you use Cat 5 for passive video, a balun is attached at both ends of the wire pair. A balun is essentially an adapter that goes from BNC to screw terminals so that you can send video down one of the pairs.

Sometimes for video, the signal is modulated and then sent down a regularly terminated Cat 5 plug/jack where it can go over a network and then it gets reconverted back to analog on the device end with a demodulator box that sits behind the TV.

Cat 5 is also used for lighting connections. DMX and DMX-512 can run over Cat 5 in lieu of using DMX cable.

And then it is also used to run audio in many home theater applications, however it can also be used in the commercial realm where the signal is sent from a wall plate to the device via a wallplate with RCA jacks. Like for instance, in one of our fellowship halls, I have Cat 5 jacks behind the audio system and I also have jacks along the wall. If I want to turn the system on and lock it down but give the user of the room access to the system via his iPod, I can simply tell him to plug his MP3 player into the wall jack and he can control the volume on his own device.

Cat 5 is also used for serial connections to turn projectors on and off. Shielded 22 gauge wire is preferred however Cat 5 will do the job.

And to piggyback on what bggowing said, the standard has gone up to Cat 5e and Cat 6, however, the term "Cat 5" is used colloquially to mention any kind of voice/data wiring... even in situations where Cat 3 is used.

[Brad Weber]

Originally Posted by bggowing

FYI Cat5 is being phased out. If you're putting new stuff in the minimum you should use is Cat5e or Cat6.

However, for video over UTP, the generic term for CAT type cable, CAT5 is actually preferred over CAT5E or CAT6. Or there is even special 'low skew' CAT cable made specifically for that application.

The main advantages I see to CAT cable include that just about every low voltage contractor works with it. They typically have reels of it with them all the time and have the tools and experience for terminating it. You can find all sorts of wall plates, floor box inserts, etc. configured to support 8P8C (RJ) jacks. All of these things tend to lead to lower materials and installation costs. Not to mention that a cable serving for video or audio Toddy could be used for HVAC controls, voice and/or data network, lighting control, etc. in the future.

There are some audio and video application that I don't think were mentioned yet. In the audio world, CAT cable is commonly used for digital snake and networked audio (Cobranet, EtherSound, Dante) applications. These system use a single CAT cable to run multiple channels of audio, up to 64 channels of bi-directional audio on a single cable is pretty common. A system with 64 inputs from the stage and 24 or more outputs, including those distributed as digital signal to system processors or to other spaces some distance away, might be able to be addressed with just a handful of CAT cables between such devices.

[bggowing]

Brad, why is CAT5 preferred for video over UTP? Is it due to the construction of the wire or the impedance of the wire?

[Mikey]

As far as audio goes having CAT5 or 5e or 6 installed can provide you flexibility in the future as well. Say you move to a digital desk you can use it to provide networking capability, or integrate Dante, Ethersound, or Cobra to transport audio bi-directionally over CAT5.

[Brad Weber]

This, http://www.extron.com/download/files...p_intro_wp.pdf, does a better job addressing the basics of audio and video over twisted pair cable than I could.

[andrewc2]

If the OP is okay with it perhaps some of you CAT 5/5e/6 guru's could recommend some baluns that are known to work well. We got one about 2 years ago but we always have issues with the video side of it, yet the audio part works just fine!

[Brad Weber]

Originally Posted by andrewc2

If the OP is okay with it perhaps some of you CAT 5/5e/6 guru's could recommend some baluns that are known to work well. We got one about 2 years ago but we always have issues with the video side of it, yet the audio part works just fine!

A detail, but I personally consider "balun", which is literally referencing balanced-unbalanced, to refer to passive devices rather than active interfaces that may incorporate function such as adjustable gain or peaking and skew compensation, but that's semantics.

I believe it is the "work well" portion of the question that is difficult as the more complete issue is really what works well in a specific situation. If I want to run 1920x1080 resolution video for 200' I am going to avoid devices that state they will handle "up to" 1920x1080 resolution and "up to" 200' as those may be mutually exclusive or maximums based on some very idealized conditions.

There is a wide range of audio and video over UTP products available and like most things, the cost is generally greater for better quality and/or more flexible devices. I typically look at brands such as Magenta Research, Hall Research, Extron, FSR and maybe Kramer Electronics. You might also want to look at some of the JustAddPower products. There are many less expensive audio and video over UTP products sold through online retailers and while they may or may not work as expected, technical specifications for these lower cost products are often lacking in order to assess whether they should work and product support if there is a problem is often limited to offering to have you return the product rather than trying to make things work.

[sempei13]

You can use cat5 to send audio (balance, unbalance, digital) or video as well as data. I think the only things that wouldn't work are things requiring 14-16 guage or thicker cable like speaker wire or even high voltage. I wouldn't try putting 120 on it, but there's probably an adapter for almost every other low voltage signal (even serial and ir).

Paul