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ericm23

Problem with Picture on 16 camera install

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Hello All

 

I have been installing CCTV systems for about three years in hotels. I use the same outdoor cameras, indoor domes, power supply and DVR on every install. I am using the following:

 

1 Vitek SAGA 16 Channel DVR

5 Samsung Day/Night Cameras with varifocal lens and housing

1 Vitek Varifocal Dome

10 Nuvico Varifocal Dome

1 24VAC 16 input power supply

 

The Problem:

 

On almost every camera there are thin diagonal lines that go from right to left across the screen. They are not really noticable when all 16 cameras are up, but when you go to a single camera it is. I have disconnected the power supply and hooked up a single transformer to one camera and it still does it. I don't know what else to try. I am running in a hall with electrical, but that is normally how I run the camera wire. I am using 18/2 and RG6. When at the camera with a test monitor there is no problem with the picture. Please Help!

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I have 5 outdoor cameras mounted to stucco and wood and the others are mounted to sheetrock and drop ceiling. The 1 camera that does not have a problem is also the 1 camera that does not run in a main bundle of wires to the managers office. I am thinking ac bleeding into the coax or 18/2, but I am hoping it is not. If it is, I am wondering how I can test/fix the problem. We keep all of our wires in a bundle very neat in d-ring runs so I don't think it should be too close to the electrical.

 

Thanks

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I took another look today for electrical wires touching my wires. Really didn't see anything down the halls. There is a fire panel on the other side of the wall from my equipment (DVR, Power Supply) and I am guessing they ran their wires by mine, though my bundle runs in a large PVC pipe to the managers office from the 1st floor hall. I read that diagonal lines could be caused by crosstalk with another high frequency wire. Have you ever heard of interference with a fire panel or fire alarm wires?

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Fire panels are direct wire 110V and NAC circuits are 24VAC or DC. Unless they ran the power for the panel with your wire I don't think this the cause of your problem.

 

Do you have two of these you could try with your power supply and DVR to see if you have a ground loop

SS403.jpg

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I have the power supply grounded to a Panamax Surge Protection. I don't have the DVR grounded, but I do get the same lines plugged into my test monitor when I pull the BNC off the DVR and plug directly to my test monitor. The DVR, Power Supply, and Monitor plug into the Panamax Surge protection; it has a ground . Do these plugs eliminate the ground temporarily to test for ground loop?

Thank you

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I went back and tried the plug you suggested. I still get the same problem with diagonal lines. I also bought a ground loop isolator and that did not work. Any other suggestions?

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They do not show up on the test monitor when at the camera, but they do show up on the test monitor when I pull the BNC off the DVR and connect strait to the Test Monitor on the DVR end.

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If anyone has DVR Viewer I have the dvr online now. You can really see the diagonal lines on some of the channels. Let me know and I can give you the IP address and password

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This is a long shot but try to power the DVR and power supply from a different outlet/curcuit. Is it at all possible to power the DVR and PS from the same outlet that you hooked the test monitor to and found it to be clean??

 

OR

 

Maybe one of the cameras is back feeding. Have you tried to disconnect one camera at a time from the power supply?? Or for that matter, disconnected all cams from the PS and connected one at a time??

 

I hate when this happens. Had a similar issue just yesterday but with 12VDC cams. I isololated the cams causing the problem and powered them with individual PS's. Drove me nuts.

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Tried an individual power supply on a problem camera with the same result. Tried a different dedicated power outlet. I am at a loss. The bundle of wires come down a wall from the second, third and forth floors and then over in the 1st floor hall. I pulled the laundry room camera wire out of the bundle from the 1st floor hall and routed it strait to the DVR and I still have the problem. The laundry room cam wire is in plastic conduit that is stubbed out in the hall and then I have it running by itself to the DVR through the laundry room ceiling. Does anyone know the main cause of faint horizontal lines scrolling across the camera image? I don't think this is a ground loop issue.

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Please PM the IP address and log in info. I'll see if I recognize the interference. Also, include your phone number and maybe we can bang heads on this if you want.

 

Let's take a step back...

 

All cams look OK at the camera?? Right?? If so, cams are "OK"

 

Take the DVR out of the loop and disconnect all power leads from the PS.

 

Hook up monitor to each BNC, one at a time and apply power to that cam only. Is there any interferance? If there is, then try powering the cam at the cam location. Is the interference still there? If not then coax is good but there is an issue with your 18/2 or power supply???? It is very possible that there is a high EMF in the chase beating into the 18/2. I have never run into this but anything is possible. The coax should shield this unless there is an issue with the coax or connectors.

 

Identify those problem runs and go from there. You may have to power the cams on each floor. All depends on what you find.

 

I think it is extremely important to separate each component on the system, find where it is good and then introduce other cams, DVR and PS, etc.

 

Also, not knowing the dynamics of the property, can you turn off circuits and see if it clears. Probably not I would assume.

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Mike. I sent you a PM with the IP info. As an update for everyone. I have isolated each camera and still no luck. However, the problem has shifted to cameras that previously had no problem and some of the original problem cameras are now clear.

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Mike. I sent you a PM with the IP info. As an update for everyone. I have isolated each camera and still no luck. However, the problem has shifted to cameras that previously had no problem and some of the original problem cameras are now clear.

 

This REALLY sounds like a ground-loop problem.

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Thanks for the IP info. I have logged on and I do see what you are talking about. Somewhat hard to see on remote view but I can only imagine what is must look like full screen locally.

 

As Soundy points out, it does look like a ground loop problem. None of the cameras are installed on metal?? Even touching the drop ceiling metal will cause this. I see it on cams 3, 11, 14 and 16. Even an offending camera causing the loop issue may not show the problem but will manifest itself in another camera.

 

Try to disconnect one cam at a time from the DVR and PS and see if it minimizes or goes away. You may have several problem cams. Also I see that 5 cams are installed on stucco. Is it possible there is metal behind the stucco and your screws are touching that?? At least tonight, we know which cams are causing, showing the problem. See if by disconnecting one cam at a time ( not 3, 11, 14 or 16 ) and see if they clear.

 

I am in agreement with Soundy. Ground loop issue it is. Especially in a commercial property as that is, anything could be happening with the buildings ground potential. Is there only one electric service feeding the building or several. If so this will cause a ground potential problem.

 

I have given you my cell number in my PM reply. Again, more than happy to talk with you in an effort to make this right. Really, give me a call if you think that will help.

 

Thanks

 

Mike

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I figured out the problem. The RG6 I was using. Too bad this job is complete. Although the owner never noticed, so I guess I drive myself crazy. Anyway I figured it out on another job I was on. I had wired a different hotel with RG59 and went back to add 1 camera. I used RG6 for this one camera. Guess which camera had the same exact diagonal rolling lines.......Replaced with 59 cleared the problem. I'm not saying there is not a ground loop problem, but I do believe the RG6 I was using was picking up electrical current.

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Did you use CCTV RG6 (solid copper core, 95% or better copper braid) or CATV/ Satellite steel core, foil shield cable?

 

CCTV type RG6 should work better than RG59, but if it was foil type, that was likely the problem.

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