Video over twisted pair

[GoBuckeyes]

I have been re-evaluating some of my cameras at our washes and have decided on some new placements. The areas that I want to mount them will be rather difficult to pull coax cable. Power for the cameras can be obtained at the mounting site, but the run back to the dvr is easily 200 ft or more.

Has anyone used video baluns to run video over cat5 cable? Supposedly you can run two cameras over one cat5 cable which is much cheaper than coax and infinitley easier to pull. Are there any drawbacks to doing this?

Is there any difference between the passive baluns that cost $15 each versus the $2 ones? I just ordered 4 pairs (8baluns) off of Amazon for $14, yet you can easily spend 10 times that for ones that look identical, RuggedCCTV included.

I read a review of one that said using baluns and cat5 offers no protection to your dvr if a lightning strike occurs. Does coax cable really offer more protection somehow to your dvr input?

Thanks

 

[Whale of a Wash]

I have used the really cheap baluns, and they do work fine. I think if the lightning hits the wire, the dvr is the last of the problems. I used thermostat 24v wire for mine., not sure if cat 5 is more or less.

 

[pitzerwm]

The only protection from coax would be the shielding, so buy shielded Cat5 or 2/4 conductor.

 

[GoBuckeyes]

Thanks guys.

I was planning on using 4 conductor 22 ga stranded alarm wire, which we seem to use for everything. Maybe I'll pick up some shielded cat5 instead.

When I get some installed I'll post an update.

 

[E.Joramo]

I use http://www.active-vision.com/Passive-CCTV-Balun-p/abl-1p03-c.htm for our video supplies. At $2.99 a piece their Baluns are a bargain.
Erik Joramo
Chief computer and Internet researcher
Fast Car Wash
Great Falls Mt.

I have been re-evaluating some of my cameras at our washes and have decided on some new placements. The areas that I want to mount them will be rather difficult to pull coax cable. Power for the cameras can be obtained at the mounting site, but the run back to the dvr is easily 200 ft or more.

Has anyone used video baluns to run video over cat5 cable? Supposedly you can run two cameras over one cat5 cable which is much cheaper than coax and infinitley easier to pull. Are there any drawbacks to doing this?

Is there any difference between the passive baluns that cost $15 each versus the $2 ones? I just ordered 4 pairs (8baluns) off of Amazon for $14, yet you can easily spend 10 times that for ones that look identical, RuggedCCTV included.

I read a review of one that said using baluns and cat5 offers no protection to your dvr if a lightning strike occurs. Does coax cable really offer more protection somehow to your dvr input?

Thanks

 

[Kevin Reilly]

I use http://www.active-vision.com/Passive-CCTV-Balun-p/abl-1p03-c.htm for our video supplies. At $2.99 a piece their Baluns are a bargain.
Erik Joramo
Chief computer and Internet researcher
Fast Car Wash
Great Falls Mt.

I just started playing with the Baluns about a month ago and have bought a bunch from acitve-vision.com also. I bench tested them because I really didn't understand how they worked. The baluns are made for long distances, but when you can use the Cat5 wire, I also tried using our spare carwash low voltage wire and they worked fine with the baluns. What makes it nice is if you want to put 3 or 4 cameras on a light pole you can handle it with the Cat wire or whatever, you just need to supply it with power. We have the mini cams in our changers and some of our coin boxes and it was a bear getting the wire to the boxes, but with the cat wire it worked fine. Then I tried using our 18ga control wire in the coin boxes to attach to a balun and it worked fine. Life's a learning lesson. Great stuff. Great prices!

 

[JustClean]

Go Buckeyes,
In my opinion this is what works out best: Run all your cameras on cat5 via baluns and a hub. Your DVR connects to the hub. The hub receives the pictures via cat5 from your camera's balun and in turn sends out 12V to the camera. No more running separate power to the camera, cheap cable and future proof if you should ever change over to IP cameras. I have been doing this for over a year now without any problems.
Here is what you need:

http://folksafe.en.alibaba.com/prod..._Power_Supply_Passive_Video_Receiver_Hub.html

Also when you crimp the cat5 cable make sure you do it according to this:
http://forums.hexus.net/networking-broadband/198006-cat5-wiring-diagram-anyone.html
otherwise it could be that you get some distortions.
Hope that helped.

 

[Kevin Reilly]

Here's an excellent video posted on utube on how to assemble a patch cable. Click on it and scroll down.

http://www.lanshack.com/make-cat5E.aspx

 

[DiamondWash]

Why not use Cat6 cable we switched most of our systems over to Cat6 wasn't cheap though

 

[JustClean]

Why not use Cat6 cable we switched most of our systems over to Cat6 wasn't cheap though

Sorry, my mistake: It should be Cat6 or Cat5e not Cat5. I am so used to call it just Cat5...

 

[bigleo48]

Cabling...a lot more complicated than just running wire.

First, the difference between coax (RG-6U or RG-59U) and UTP (unshielded twisted pair..various speeds to Cat6) is one balanced vs. unbalanced. With coax the signal rides down the center conductor and it has a shield for grounding potential. The UTP is balanced, so signal runs down a pair of twisted conductors (pair for each direction). They also have different characteristic impedance. So the balun (balanced/unbalanced) matches this.

The differences between Cat-3 to Cat-6 is mostly twists per foot in the pairs. The twists make the signal leak into itself. For video with shorter distances, cat 3 will work, you can use pairs for power (12v) but it has high loop resistance, so the voltage can drop significantly and cause problems. Also you are better protected from noise ingress with coax due to the shielding. You can go to a STP (shielded twisted pairs), but they are a little tricky to install. It you don't use the correct connectors and miss install, you can the shielding can act as an aerial and ingress more interference into the pairs. If you ground both ends (as most do), you can cause a ground loop (difference in ground potential between both end points) and mess the equipment up (I've seen ground loops of over 50 volts destroy equipment).

So if you can use coax and separate power leads, do so. But I know its not always possible, so baluns might work out fine. I would stay away from florescent lights fixtures, power cables, motors, etc and keep distances as short as possible. If you want or need to use shielded cable, I would talk to en experienced cable installer.

 

[JustClean]

For myself, I have no idea what I am talking about BUT somehow it works very well
Most of my 16 cameras run on Cat-5e cables over the balun hub and I am very, very happy with it. No worries about getting power to them, no worries if I ever need to upgrade to IP cams and it's cheaper. So I would do this again any day. However, the longest distance I have is about 200ft.

 

[bigleo48]

JustClean,

It's nice when it works out well, the vast majority of cabling jobs I see are terrible and still works fine. However, when a problem creeps in, that's when things can go badly and most are unequipped to understand and troubleshoot the problem. I guess I feel that using UTP in a coax application is like using a screwdriver to open a beer Sure it will work, but...

 

[mjwalsh]

JustClean,

It's nice when it works out well, the vast majority of cabling jobs I see are terrible and still works fine. However, when a problem creeps in, that's when things can go badly and most are unequipped to understand and troubleshoot the problem. I guess I feel that using UTP in a coax application is like using a screwdriver to open a beer Sure it will work, but...

Big Leo & others,

I agree with both of Big Leo's detailed posts on this issue. Having used twisted pair (plain old twisted pair telephone line) cable since 1982 for video on a 1200 foot line ... It seems like coax would have had its advantages. I know that the cable company uses coax which seems to have the added benefit of running a higher bandwidth for data (if needed in the future) than twisted pair. Of course the equipment on both ends could be more expensive ... I am not sure ... otherwise we probably would all be using fiber optic more. I am sure lengths make a difference besides just the quality of the terminations etc.

mike

 

[bigleo48]

Using UTP (like CAT5) for analog video (not IP cameras) is a different application than Ethernet/IP applications. Its baseband (unmodulated) & simplex (one direction). The bandwidth required is well withing the capability of the wire and you don't have the NEXT (Near End Cross Talk) problems with data when you exceed distances over 300Ft. So it should work fine if terminated correctly. Just to give you a feel for the differences in CAT5 cable, you can have a differences in the following: Gauge, Wire Type (stranded or solid), Shielded or not, Oval or Round Jacket, Plenum Jacket or regular PVC. These types of differences may require different connectors to make a good connection.

Then there is the environment you put it in (ground and equipment quality, conduit or none, splices, termination blocks, interference sources, etc).

I guess like anything else, there is more to it than you see on the surface.

 

[GoBuckeyes]

Come on guys. It was sounding like Cat5 with baluns was going to be as good as sliced bread! Now that I've bought the cable and baluns you're making it sound as plausable as catching a unicorn.

I guess I will be falling into the 'try it and hope for the best' category, as I don't understand most of the technical stuff you said.

 

[bigleo48]

Buck,

In your original post you said you didn't have the room for coax...so that limits you to UTP and baluns.

In my posts I simply wanted to indicate a little of the technical and to get you thinking about potential problems...especially noise and grounding. When you don't take it lightly and are more careful, your chances of success are higher.

 

[GoBuckeyes]

Leo, I was just kidding. I do appreciate all the feedback and suggestions.

Now that I have purchased some components, let me explain what I was hoping to do with it so you can tell me what you think. I purchased Cat5e UTP and passive baluns. Since there are 4 pairs of wire in the cable, I was hoping of pulling one cable from my dvr through my trough to a central location on my roof and from there splitting off to four separate cameras. This particular wash already has the cameras mounted, but the coax cable has really disintegrated from sun exposure. I was planning on using the existing power wires for the cameras, but using the cat5 for video. When I get to the central location, where I want to split off to the cameras, is there a better way to splice the cat5e? Can I crimp or do I need to solder?

There is also a scenario where, for one camera, I would like to use the cat5 for video and power. Is that ok or not? If its ok, could I run two cameras and power?

 

[bigleo48]

Yeah I figured so by the Unicorn comment

To maintain true cat5e performance, you would need a cat5e terminal block (like a 110 strip). So you would bring the 4 pair cable in and wire the 1st pair (white/blue) to the first position on the block. Then the second pair (white/orange) to the 6th position, then the 3rd pair (white/green) to the 11th position and finally, the 4th pair (white/brown) to the 16th position. You'll obviously need to do this at both ends. This is also assuming the video balun uses the 1st pairs (White/blue). On the opposite side of the block you would wire very cable the same. 1st cable, (please keep in mind that White is alsways the primary color

) Blue-Orange-Green-Brown then a space for the Slate color you don't have in a 4 pair cable, but is allocated in a 25 pair 110 strip.

. Then continue with cable two, three and four.

Now soldering would change the characteristic impedance of the cable, but might work ok in this case. For data this would be a big no-no.

Finally, the low voltage might be ok on a separate pair in the same cable. Just don't mix them up as you would likely fry the camera if you put 24vac in the video out.