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Louis2

How long will RG59 Siamese 18/2 cable last?

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I’m a welding instructor for a technical school. We have a professionally installed CCTV security system, Mace box color cameras with RG59 18/2 Siamese cable.

 

The company that originally sold and installed the system to us sold out to someone else. We started having trouble with the system and were told that the video cards in the computer recorders were going bad and the cost of replacing them would not be worth it. We have purchased one new dvr from them, but a lot of the cameras on the good dvr and the old one are showing interference lines, like the old televisions did when you were turning the antenna trying to tune it in. You can guess I’m not a youngster.

 

We do not have a lot of funding as we are a state ran school and budgets are becoming as bare as “Old Mother Hubbard’s Cupboard”. We do not have anyone trained in this field and computers are kind of a hobby of mine. I can usually get lucky when I work on computers, but not having much luck figuring this stuff out.

 

We have been taking cameras to the office where the dvrs are and connecting them to a short cable to check and see if they are good. Ones that work good on the short cable we reinstall. We have reinstalled some of the twist type bnc connectors on camera and dvr end. This has helped on some cameras, but on some of the others it has had no effect at all. The picture was still just as bad.

 

Some of the 18/2 power cable has the coating just flake off when we are connecting it to the cameras. The lines have not been moved since installed about 6 years ago; they are lying on top of a drop ceiling. The system worked well when it was originally installed.

 

I had two cameras close to each other in my shop. One camera was bad so I have used the power cables from it to operate the good camera instead of the power cables ran to it. Doing this gave a picture that while still not great at least we can make out who people are as they walk around in the shop. With the original power lines ran with its video cable the picture is so bad we wouldn’t be able to use the video for anything.

 

I have read that it is recommended you replace the ends about every two years or so and have decided we should get some of the compression type bnc connectors to replace our ends with.

 

I’m wondering if we should run new cable also. Does this cable go bad after so many years?

 

Thanks,

Louis2

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I'd buy a couple of ground loop isolators and/or a new power supply for the cams and see if that fixes your problems first. Not saying you don't have some bad cables but noise in analog cameras from ground loops through their power supplies is pretty common.

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RG59 is extremely robust and if indoors I can think of nothing that would put a lifespan on it short of mechanical damage. Your problems will most likely be caused by the terminations or (as stated) your power. Has the power configuration been changed from when your old system was working.?

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RG59 is extremely robust and if indoors I can think of nothing that would put a lifespan on it short of mechanical damage. Your problems will most likely be caused by the terminations or (as stated) your power. Has the power configuration been changed from when your old system was working.?

 

No the power configuration has not been changed. I have switched both the bnc ends we had on one of the lines. The ones I replaced them with were used twist on ones, but it did not change the video quality. The picture has so many diagonal lines of snow that you can barely make out what the items in the room are. What are ground loop isolators and how could that help with a power problem?

 

I would also ask if I have to have a special tool for the compression fittings and can I reuse the fittings if I don't get it on good the first time?

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RG59 is extremely robust and if indoors I can think of nothing that would put a lifespan on it short of mechanical damage. Your problems will most likely be caused by the terminations or (as stated) your power. Has the power configuration been changed from when your old system was working.?

 

No the power configuration has not been changed. I have switched both the bnc ends we had on one of the lines. The ones I replaced them with were used twist on ones, but it did not change the video quality. The picture has so many diagonal lines of snow that you can barely make out what the items in the room are. What are ground loop isolators and how could that help with a power problem?

 

I would also ask if I have to have a special tool for the compression fittings and can I reuse the fittings if I don't get it on good the first time?

 

It doesn't sound like an earth loop problem.

Diagonal lines of "snow" is almost certainly an electrical interference problem. Make sure your cables are well away from sources of electrical noise , especially fluro lights. I'd be using quality BNC connectors to start with (not the twist on). You will need a special tool for the compression fittings. You can get re-useable compression fittings (called bluecaps in Aust)

As a side note is this interference permanent or could it be due to arc welding

.

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It’s a permanent issue. Scattered cameras throughout the building have issues with this to varying degrees. This one electricity class camera is the worst. They are all the same whether we have the power on in the shops or not.

 

I have read about the fluorescent light issue. The cables should be three feet away from any lights. That’s just it, our cables have not been moved since they were installed and this issue has only cropped up in the last year or so.

 

The high school we lease our space from has installed a wireless internet system in the building. There is a wireless router mounted in the ceiling on the outside wall of the electricity class, could it be interfering with the signals?

 

I would still think that all the cables run down the hallway ceilings more or less together and therefore they would all be affected by any interference.

 

If we have to use a ground loop isolator should we install it on the camera end or the dvr end?

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Can you try hooking the bad cams straight into a monitor to make sure the DVR isnt creating the issue. If there is something that happened at some point like new electrical/electronic devices maybe try powering them off (wifi device). If its possible pop breakers one at a time to see if you find a circuit that is creating the problem and go from there.

 

Also can you substitute the power supply while testing a particular camera. Do you have a single transformer type power supply powering all cameras and does it feel hot (too hot) to the touch.

 

Indoor cable kept away from moisture should last many years, outdoor rated cable should be good too. Certainly outdoor weather conditions over the years will increase the odds of failure over time, but could be decades.

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Can you try hooking the bad cams straight into a monitor to make sure the DVR isnt creating the issue. If there is something that happened at some point like new electrical/electronic devices maybe try powering them off (wifi device). If its possible pop breakers one at a time to see if you find a circuit that is creating the problem and go from there.

 

Also can you substitute the power supply while testing a particular camera. Do you have a single transformer type power supply powering all cameras and does it feel hot (too hot) to the touch.

 

Indoor cable kept away from moisture should last many years, outdoor rated cable should be good too. Certainly outdoor weather conditions over the years will increase the odds of failure over time, but could be decades.

 

Yes we move the cameras to the dvr and connect them with a short cable to check them. Our electrical teacher has checked the power lines at the cameras. We have 12 DC volts when not connected and 11 point something (can't remember the exact number) when connected under a load. Good idea about tripping the breakers to see how they affect the video signal.

 

I think we are going to replace the ends with compression ends and check the paths of the cable to make sure they are away from lights and other electrical equipment. I also want to get a couple of ground loop isolators to try on some of the lines at the dvr to see if that will help in some of the extreme cases.

 

Thanks to everyone for your help. I'm glad you guys aren't like the computer techs that ask if you have tried turning it off and then back on again. I always want to come back with a smart "now why didn't I think of that?"

I have learned a lot from this forum. The information has helped me to form a plan of action where before I felt we were just poking around in the dark.

Louis2

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OK, still working on it.

The camera in the electricity shop had a bad picture with these interference lines running diagonally through it, so bad you could not make anything out. I changed to another camera we had. It was one of the original ones we purchased also, about 6 years old. The picture got a little better. You could make out that there were some desks there but not much of anything else. Then we switched cameras to a new one that we just bought last month. The picture is really pretty good. It still has interference that you can see, but you can now see someone standing there and tell who it is. We could live with this picture, it is useable.

 

I want to know if it is possible the cameras are going bad and the strength of their signal is getting weak and the interference we do have affects the picture more?

 

In most of our picture interference issues a new camera helps, but doesn’t totally give a clear interference free picture.

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Are all these cameras powered by one power box? What's powering the system and if it's individual power supplies or combo 4-8 way power supplies, please let us know. I would try the ground loop isolators on the bad runs as well, on the dvr end. Keep your newest cameras in line and try the GLI's in line and see if it clears up.

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Mace security cameras and power supply. 24 cameras in all. 8 cameras on new dvr. 16 cameras on old cpu based system that the video card is giong bad in. Only a few camera slots still work on the old system and some of them blink in and out about every 30 seconds or so. We don't have all 16 connected to the old system any more, just attatched about 10 cameras to slots that worked sometimes. Mace 12volt DC power supply. 12 cameras on one power box and 12 on the other. Cameras on the new dvr and the old system have problems. We have swapped the video cables around on the dvrs, it doesn't help with the picture quality.

 

I'm ready to ask someone to give me a call. This stuff is just too stange to try to explain with text. My students leave 2:00 pm central standard time and I would be free to talk if not in any meetings. If anyone would like to offer maybe we could set up a time and date through instant messaging or email? I don't expect to figure it out, but I sure would like confirmation that I'm not crazy....

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You mention the 2 separate power supplies it would be interesting to know if the bad cameras were all on the same power supply. Can see if you can find the power wires for one of your problem cameras and isolate it with a substitute wall wart to see if there is a difference.

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We have ran seperate 18ga power lines to a camera that was close by. It did not change the picture that much. I have been wondering if there was a way that the camera's own power wires could be the problem. The coating is breaking off of the red hot wire at some of the cameras. In the 6th paragraph of my original post I explain about how switching to another power line helped in one instance, but it has not helped for any other cameras.

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We have ran seperate 18ga power lines to a camera that was close by. It did not change the picture that much. I have been wondering if there was a way that the camera's own power wires could be the problem. The coating is breaking off of the red hot wire at some of the cameras. In the 6th paragraph of my original post I explain about how switching to another power line helped in one instance, but it has not helped for any other cameras.

 

 

If you want to prove once and for all if it is a power or earth loop problem then disconnect one of the bad cameras from its power source and run it on a 12V battery.

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Power at the box is putting out 12.16 volts.

Yes the wire is good. Don't know about the 95%, but it is copper. On another note, everyone is always talking about the connections and how important they are. We have one that has a screw on bnc connector and the wire can easily be pulled out and put back in. I mean its just loose as it could be. It has one of the best pictures we have.

 

We need a smilie that's scratching his head, with a puzzled look on his face. I would sure over use it.

Edited by Guest

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Have you ever tried using a power supply that was not one of the original ones? Might also be worth trying to isolate some of the cctv equipment if possible, maybe shut down both power supplies and DVRs and test a KNOWN GOOD camera straight into a monitor. Then you could test the known good camera on some other lines to prove the cables good/bad.

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