Cable Length and Correct Cable

[Bob La Londe 0]

I recently have gone through some headaches with a system. It is using Toshiba IK-64WDA cameras with Tamron 2.8-12mm auto iris lenses. They are all tied to a Dedicated Micros DS2.

 

Here is the problem. An electrician ran the cable for the job. Because some of the distances I specified RG-6 95% Cu. I also specified that a 16X2 overall jacketed should be home run for each camera location to a central location where I intended to install an Altronix multi camera power supply.

 

The distance to the furthest camera is about 850 feet. The actual cable length may be 900 feet when you count the various places where it comes up and down to J-boxes etc.

 

Problem 1:

Initially they started to install CATV cable with aluminum shield. I stopped by the site and complained. I very carefully explained that it needs to be RG-6 95% Cu which is designated as a CCTV cabel not a CATV cable. They supposedly replaced with a Belden cable that was marked RG-6 95% TC. The TC supposedly meaning tinned copper. It looks and performs like aluminum, and it has a foil that looks and performs like aluminum.

 

Belden swears the cable the electrician claims they used is adequate for CCTV applications in the distances run. I called Belden and the guy I spoke with swore it was the best cable Belden made. He refferenced broadcast applications many times. The cable is labled for 3ghz applications. That would make it fine for CATV with hyperband and wonderful for DSS satellite applications. That does not mean to me that it would be good for the low frequency signal of composite video.

 

I have been having bad problems with signals from all the furthest cameras, and occassional problem from most of the cameras. The problem is a badly distorted image that the DS2 keeps showing as camera fail. When I hook them directly to the monitor I get a little side to side distortion. Some are worse than others. I get a good picture at the cameras of course.

 

Problem 2:

I have discovered that of my 6 worst cameras the cable for six of them has been spliced in atleast one location. At least four of the cables to these cameras has been spliced in a second location. The electrician used Radio Shack screw on F connectors and F bulkheads. I replaced them at one location with good crimp on connectors. In fact I respliced them twice. Once using BNC connectors and BNC bulkheads and once using good crimp on 0-ring sealed F connectors with F bulkheads. I seemed to get marginal improvement with using crimp on F connectors for the splice. The other splices are in difficult locations to resplice and I did not locate them until nearly the end of the day. Two of the secondary splices had been stuffed up inside of a conduit to hide them, and two other were in a J-box nowhere near a run to a camera. I suppose they never figured anybody would open that box and look. There may be more splices out there. I have not yet opened every box on the premsie and pulled back on all the cables to find out.

 

Problem 3:

Instead of running a pair pair to each camera like I specified the electrician ran 120VAC to each camera. In fact, they ran 110VAC into the camera housings for each camera. I wnet ballistic over the stupidity of this. Their job was done and becasue te facility was basically complete it was no longer practical to run new conduit. There was no possible way to run power wire to the cameras now. Finally they agreed to put up a large J-Box next to each cameras and put a 120VAC outlet inside the J-Box where we could plug in a transformer. WE ran a flex fvrom the J-Boc to the cameras housing and installed a transformer to power the camera and housing.

 

I am convinced that the solutions to this problem is to jerk out the TC cable and all of the splices. Then replace it with RG-6 95% Cu with no splices anywhere. I estimate the price to the customer to do this at about $3800 for cable and $1500 for labor. Since it is not a problem of my causing I refuse to pick up the tab.

 

I have considered using composite video line amps, but because this is an outdoor application the heat may be an issue for their longevity. There are J-Boxes near each camera, but it is out in the sunlight. They still cost a fair amount, and again I am not willing to pick up the tab. Before I offer this as a slightly cheaper option to the customer I want to make sure it would work. The last time I checked a good line amp for composite video was around $300. Multiply that by twelve cameras plus the labor to install and adjust them and its close to the same price as replacing the cable.

 

What other possible solutions do you suggest?

[AVCONSULTING 0]

Try this first. See if your local distributor will get you one on a trial basis.

It might just do the job.

 

ftp://www.pelco.com/AESpecifications/EA2010_series.RTF

[Bob La Londe 0]

The link does not work.

[rory 0]

try this link.

 

http://www.pelco.com/products/power_comm/videoconditioning/eqamps.aspx

 

The splice shouldnt matter once it is done right, but at that distance it would be better not to have it anyway. Would it be cheaper to re run Cat5 cable/twisted pair with an active Transceiver and transmitters at each camera?

 

Rory

[cctv_down_under 0]

The splices will indeed be a problem, you should run a clean run and use a quad shieded RG6 if you have to use RG6 I prefer Fibre over long runs, you can buy Distribution Amps cheaper than that, you could buy a 8 in 16 out for around $200, but if it were me I would run Fibre, that way no interference at all, it originally looked to me like it was a power problem, but if you have made the changes now and it still does it I am betting on the fact that it is an earth loop or more likely, to many splices.

 

Always put your requirements in writing on big jobs and always use installers that you know have done work like this before.

 

Beldon cable is usally pretty darn good.

 

I hope this helps,

[rory 0]

yep, electricians can be your best friend or worst enemy on CCTV jobs, depends which one you use, or what mood they are in! )

[cctv_down_under 0]

Aint that the truth

[ericm23 0]

We recently installed 32 toshiba ik-6410a day/night cameras with 2-12 mm auto iris DC lenses. We are using RG6 and 18/2 power wire hooked up 24 VAC. We are using Speco DVRs.

 

The problem is that every 5-10 min the picture will move to the right with a line of black showing and then the color becomes distorted and bright for a few seconds and then everything goes back to normal. This happened during the install while adjusting the focus, so I think it may have to do with movement; however, there are 9 existing toshiba cameras that we moved to our system that don't have the problem. All new cameras are having the problem, but at different times. Could it be movement (our type brackets) or some setting effecting the new cameras?

 

THANKS

[survtech 0]

Did the electrician run the 110VAC in the same conduit as the video? That will cause you problems. Video cables should be separated from power by at least one foot per 100VAC. Also, what is the part number of the Belden video cable?

 

It doesn't matter if the cable center conductor is tinned, as long as it is solid copper core. You can test by bending the center conductor. If it bends relatively easily, it is copper. If it is very hard to bend, it is probably copper clad steel, which is unsuitable for CCTV - especially in runs longer than 100ft.

 

You can also test with a small magnet.

 

The shield is as important as the center conductor. It has to have a low resistance, just like the center conductor. Aluminum foil is not a problem, as long as there is sufficient copper (not steel) drain wire running with it - tinned or not.

 

Every splice is also a potential source of problems. It is best to avoid them wherever possible. If you do have to splice coax cables, "F" connectors are not suitable for CCTV splicing. Use high quality BNC connectors with gold-plated center pins. I've seen nickel-plated center pins corrode and cause poor connections. Compression-type BNC connectors are very good.

 

If there is a potential for moisture getting into the splice (underground or outside), use compression connectors with suitable splice boots packed with silicon dielectric compound (available at auto parts stores).