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Wavy video with Cat5

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I was recently contracted to install 9 cameras on an existing DVR system.

 

The existing outside cameras are run with rg59 Siamese power 24v A/C

 

They look pretty good with minimal interference.

 

I installed the 9 12V cameras using Cat5 and surge protecting video baluns.

 

ALL the cameras are Wavy! Not horrible, but I'm not happy with the results.

 

The shop has ALOT of differnt voltages running through it. 120, 220 ect. It's an old factory.

 

I tried ground loop isolators. This didn't help the problem.

 

I was carefull to keep my runs away from power lines in the building. my close cameras 25-50 feet look as bad as the longer runs 400-500 feet.

 

Did I make a mistake running cat5e??

 

I noticed when I wiggle the balun connection at the dvr I actually see the video get better! Do I have bad baluns?

 

Should I be using active baluns?

 

Please help....I'm not sure what to do....

 

The DVR is an Everfocus model 16 channel and has monitor outputs for each input. Could the fact that the outputs are not capped be the issue??

 

Remember there are 5 cameras that are working correctly....

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Have you tried different baluns?

 

Disclaimer: As much as I love using CAT5E for CCTV, and have had overwhelming great results, there is one instance I've had where it failed. I had waving and distorted, generally crappy video. I replaced everything, the camera, the baluns, the DVR, tried different power supplies, different circuits for power, different DVR, and even pulled a 2nd CAT5E siamese cable only to get the same results. The was no high voltage lines along the wire path. I ended up pulling RG-59 and it worked great. No clue why it wouldn't work with CAT5E.

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Did an experiment today.

 

I took a box of cat5e (about 200 feet) and used blue for video and orange for power.

 

Result? Wavy lines.

 

I took a second box and put the power on one cable and the video on the other.

 

Result? No more wavy lines.

 

This goes against all the installs I've ever done...but I'm willing to install cable for power only.

 

However, there will be furture installs but these runs will be in excess of 300 feet. I think Cat 5 still is the way to go...isn't it?

 

All that being said. I don't get it. it MUST be either a problem of the A/C coming into the building or the supply is crap...I have yet to nail it down 100%

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Which color wires did you put the cameras on?

 

Blue video, Orange power...not that it makes a difference...

 

Polarity was checked.

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Have you tried different baluns?

 

Disclaimer: As much as I love using CAT5E for CCTV, and have had overwhelming great results, there is one instance I've had where it failed. I had waving and distorted, generally crappy video. I replaced everything, the camera, the baluns, the DVR, tried different power supplies, different circuits for power, different DVR, and even pulled a 2nd CAT5E siamese cable only to get the same results. The was no high voltage lines along the wire path. I ended up pulling RG-59 and it worked great. No clue why it wouldn't work with CAT5E.

 

No, but the thought has crossed my mind to use a different balun...I will try that as I try to find the best solution...

 

This is my first install of Cameras as my own company.

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What size Transformers? What is the amp requirements for the camera's?

 

The transformer is 5amp...Cameras range from 200 to 400mA. I have 6 cameras installed of the 9 I plan to install.

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JTA, I dont use 12volt very often...but If you can try to run all your power isolated on 18-2. After many hit and misses Ive stopped running any power through cat for typical cams (not IP) too many issues can arise, some cams/setups are finiky using balums...interesting on a install used two differnt balums NVT and Nitek on a outdoor isetup..... approx.360ft run... ground loop and some snow flicken right from the start, replaced the trans balun with a cheap 10dollar OEM groundloop blocker type balun and picture cleared up but went further and isolated the power on a run of 18-2 and picture went to normal ....go figure? A lot of installers here on the forum have had good luck with power/video on cat I dont take the chance anymore gonna pull wire anyway so I spec another

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HAD ONE JUST RECENTLY, WOULD ONLY WORK AS B/W, SO USED OR AND OR/WH, BR AND BR/WH FOR POWER , SOON AS I DID THAT CAMERA WENT TO COLOR, USED TWO PAIR FOR POWER AND ONE PAIR FOR VIDEO. ALSO DID THE SAME FOR A MINI PTZ DOME AND WORKED GOOD THAT WAY. WAS ONLY 125' RUN THOUGH.

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However, there will be furture installs but these runs will be in excess of 300 feet. I think Cat 5 still is the way to go...isn't it?

 

Cat5 is good for existing cable, multi building connections, or runs over 750' but for shorter than that RG59 is best, IMO.

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However, there will be furture installs but these runs will be in excess of 300 feet. I think Cat 5 still is the way to go...isn't it?

 

Cat5 is good for existing cable, multi building connections, or runs over 750' but for shorter than that RG59 is best, IMO.

 

Well, since I'm going to have no choice but to run more cable I have some RG6 that I aquired for free! I'm going to run that and use the cat5 I ran for power only.

 

HOWEVER, this company is going to need more cameras run. The runs are over 700 feet and I'm concerned I'm going to have the same issues again if I run coax to the longer runs!

 

I'm considering using one cat5 as a trunk for video back to the DVR. That is using one cat5 for 4 cameras.

 

Does this sound like a good idea??

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Make sure the RG6 is not aluminum braid if you do use that.

 

Multiple runs at 700', cat5 could come into play with that. Personally I would use active UTP for anything that far, but power the cameras locally (at the cameras). NVT (and others) have transceivers, etc with built in ground loop isolation. Make sure the Cat5 is in conduit though, its not as strong a cable as Coax otherwise troubleshooting any glitches in the cable could be very time consuming with those distances.

 

Either way, I would not use cat5 for power at that distance, in fact I would just power the cameras locally for any cable at that distance, so if you have 4 cameras concentrated in one location say 700' away, put in a 4 channel PSU there instead. if concerned with ground loops, price in isolators into the project.

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"I noticed when I wiggle the balun connection at the dvr I actually see the video get better!" "Remember there are 5 cameras that are working correctly...." your remarks give a good insight where you can begin to troubleshoot. Check all your new terminations to the DVR, are you going direct to the dvr with baluns,is there a tight solid contact with the bnc are the twists within the limits to the baluns, try observing direct to monitor one of your new cam (12volt ones) bypassing the dvr observe the signal on a service monitor (hand held etc) and see what you get. If its clean then you know your next step is to concentrate on the suspect wiring to your DVR, perhaps using a UTP mini hub then wire direct bnc output to bnc imput on your DVR, may resolve some mess of cat wires getting loose or making poor contact, Rory has raised some good info on the RG issue if you do pull new make sure you are using proper cable...RG59 copper 95% or 6 with copper.... no aluminum. How far are your exsiting working 24v ac cams on the RG59 that are giving a normal signal? Can you swap a 12volt cam to the RG see if it you get a normal pic, do you have access to local power near one of the added 12volt cams where you can try a single 12volt transformer and observe the picture to test, you maybe picking up a lot of ac pollution just within the building itself, you stated that it was a older site with various voltages traveling...is all your wire exposed, are any runs outside of plant underground...poles/building face etc... a lot of these issues can be checked by trying various swaps and interconnects by using the exisiting cables and your added sources before you spend additonal T&M on more gear into the mix. Nothing is set in stone when it comes to power and signal ( I laugh at the market catch phrase "plug and Play" better to say plug and Pray, as the various comments attest to if you search this forum, there are certain guidelines to follow for sure on cable etc. but in the field often issues arise and you can only try to resolve by trying various configs, till you aquire a good result that your clent and you will be satisfied with. As I said before I avoid running power/voltage on cat when I use baluns and by using isolated power often resolves issues that you are finding. Using cat for long runs as a power wire you must consider the voltage drops and related issues such as protection,mechanical durability (placement/pull etc) A good rule of thumb prior to hangin cams is to approve a plan starting with all the power considerations, voltages, wire, etc. I have found retro fits often harder than new installs but you say that the exsisting system was clean with 24v take a close look at the 12volt being thrown into the mix. Some dedicated 12volt cams play well within 24v systems with converters some dont, mixing 24 and 12 volt may cause problems. In so far as design issues I just returned from a site where the clent had run #14romex from a outdoor recpt spliced on a #12 middle of run to a outdoor box 100ft where he wanted me to place a power box.... aside from the wrong type/size wire spliced (to a 20amp breaker) I noted the fault and code/violation he didnt want to correct it I refused the job.

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Try using individual 12VDC "wall warts" for the camera instead of powering them all of the same transformer. This has overcome similar problems for me in the past.

 

Doug

 

What size Transformers? What is the amp requirements for the camera's?

 

The transformer is 5amp...Cameras range from 200 to 400mA. I have 6 cameras installed of the 9 I plan to install.

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I would follow Rory's advice and keep the power close to the camera's especially using 12vdc, if not possible then use seperate power wire.

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Here are a few things to consider....

 

SKEW .. if not using actibe baluns then you ,ay run into a problem called SKEW, this rarely comes accross as wavy lines, but it can do, it usually looks like ghositing near any bright image...usually to the right of the image...this is caused by the colour burst arriving at different intervals based on the twists and the cut in the cable, it is very very common.

 

You should never ever use CAT5E on a passive balun!

 

Next consider that CAT5 does not have much protection or sheilding against interference, so if there is power or other things that could cause problems then re-route the cable.

 

Lastly before you go RG6 and risk shimmer effects, why not go for a Bosch LTC0485 camera, the reason is that it has cable compensation built in, this means it can handle huge runs and can automatically measure the impedance....now they ar not cheap but considering you have to re run a cable, it is worth considering.

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What brand of Baluns did you use? It could be the baluns but if you are using a good quality balun then please note the following options.

 

he quickest way to clean up the vdeo signal is to install active (powered baluns on one side of the feeds. This will clear your images up instantly.

 

Another way (less expensive) is to use individual power supplies. The reason this will work in most applications is that with passive baluns and a common power supply you provide a common ground to all of the cameras and the passive baluns will provide a clean path to ground that will be common to all the cameras. This is a perfect scenario for "hunting", ground loops to occur especailly where there are differences in the length of your cat5 cable and 12VDC power applications. When you install individual power supplies the common grounding point is no longer available and in most cases it will help to solve your problem

 

The active balun option will be the surest way to solve your problem, but it is more expensive.

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found this problem the otherday and we used HUMBAR Rejecters, turned out the other cameras which were on another building, were using mains from a different supply (actually differnt Phase) to the one of DVR and monitor. sorted out no problem.

 

as for your problem the other post are more likly to be right as im new ish to this but worth keeping in mind

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I just talked to NVT tech support about a proposed installation involving existing buried conduit.

 

4 cameras needed to be installed in a building that the only way to connect was via a buried conduit with 480 volt cables in it.

 

The NVT tech cautioned the intelligence of doing so but said technically, the 480 volt cables would not interfere with the CAT5 video. He said balance cables like CAT5 are naturally immune from interference and do not need shielding.

 

I am puzzled about your claim.

 

Randy

 

 

Here are a few things to consider....

 

 

 

Next consider that CAT5 does not have much protection or sheilding against interference, so if there is power or other things that could cause problems then re-route the cable.

 

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I am puzzled about your claim.

 

Dont be puzzled, please test it out for us.

 

I have had the same experience with cat5 and high voltage as cctv_down_under in that it has experienced higher levels of interference.

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I forgot to include the NVT tech also specifically stated that active baluns should be used.

 

Apparently the Chicago Transit Authority recently installed a large CCTV system running in the same conduit as the power required for the rail system.

 

 

 

I am puzzled about your claim.

 

Dont be puzzled, please test it out for us.

 

I have had the same experience with cat5 and high voltage as cctv_down_under in that it has experienced higher levels of interference.

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I just talked to NVT tech support about a proposed installation involving existing buried conduit.

 

4 cameras needed to be installed in a building that the only way to connect was via a buried conduit with 480 volt cables in it.

 

The NVT tech cautioned the intelligence of doing so but said technically, the 480 volt cables would not interfere with the CAT5 video. He said balance cables like CAT5 are naturally immune from interference and do not need shielding.

 

I am puzzled about your claim.

 

Randy

I myself am puzzled by NVT's claim. The National Electrical Code specifically says that low voltage and high voltage cables can not share a conduit. This is not the case with fiber since glass is not a conductor. Did the Chicago Transit Authority co-locate twisted-pair with 480 volts within a single conduit?

 

It is not only a question of possible interference from the high voltage to the video signals, but also a safety issue since the high voltage can induce itself into the low voltage cabling, causing a shock hazard.

 

From Blue Jeans Cable:

 

"Running Signal and Power Together

There are two good reasons not to run signal-carrying cables and power lines in a conduit or other enclosure together. The first is, simply, that it's a great way to get a lot of EMI into your signal chain. The second is, as you've probably guessed by now, that it's against NEC requirements. Video and audio cables may be run in raceways with one another, but NEC prohibits running video in the same "raceway, compartment, outlet box, junction box, or other enclosure[]" with power circuits, NEC 820.52(A)(1)(b), with minor exceptions, and prohibits running audio in the same "cable, cable tray, compartment, enclosure, manhole, outlet box, device box, raceway, or similar fitting" with power circuits, NEC 725.55(A), unless separated by a barrier. Coaxial cable is required to be separated by two inches from power cable, unless either it or the power cable is enclosed in a raceway or they are separated by a "continuous and firmly fixed nonconductor," NEC 820.52(A)(2)."

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I am having a similar issue with a camera system I recently installed. We have 13 cameras indoor and outdoor. When they are hooked up to a regular 16 port power supply, I get waves and lines in the video. The strange part is that when I hookup an individual power supply to each camera, the waves and lines go away.

 

The runs on these are a minimum of 200 feet up to about 600 feet. We ran cat5e riser cable to GenIV Baluns on each end and Have Gen IV outdoor cameras (G4-HRS-480DN) and CD-35iR-VPW25 indoor domes.

 

Any suggestions

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You could be getting ground loops within the power supply. This is indicated by the lack of problems when you use separate supplies. In standard power supplies, the individual (+) and (-) connections for the cameras are common to each other; with only a fuse separating each output.

 

Try an isolated power supply. If you are using 24VAC power, here are suitable ones from Altronix:

 

8-camera - http://www.altronix.com/index.php?pid=2&model_num=ALTV1224I

16-camera - http://www.altronix.com/index.php?pid=2&model_num=ALTV2416I

 

Altronix makes other versions using ptc's instead of fuses and with various power ratings. Unfortunately, if you are using 12VDC power, they don't make isolated versions.

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