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MAX CAMERA LENGTH RUN RG59/U 95%BC CCTV 1M BX BLK HONEYWELL GENESISHelpful Member!(2) 

aarenot (Vendor) (OP)
6 Dec 07 12:07
I was subcontracted to run some RG59 cable for a security company who underestimated the distance of many of the cable runs.   Two of the cable runs have poor, or no video signal due to, in my opinion, the excessive length of the cable runs.   I have been given data stating not over 600 feet is recomended, but that it is rated/guaranteed to support up to 750 feet.

I am of the opinion that since I was contracted simply to run the cable, and make some BNC connections, the lack of signal in an over recomended length cable is not my issue.   Since the application conditions exceed the recomended spec of the materials provided performance is the responsibility of the contractor who designed the system, not myself who was contracted for labor only, not as a consultant.   I was told that all of the runs were within acceptable parameters by my customer the contractor who is the subject matter expert since they are the security company.   

I would like to know how long people have experienced success with 24V camera cable lengths through a factory setting.   Also, how long you would guarantee the full performance of an RG59 cable run for CCTV.  

The cable was provided, cable paths dictated by the contractor so I was not even a consultant, just simple labor.   

Let me know what you think.   I did inform the customer of their underestimate of lengths prior to running the cables, so they were aware.

The overall length of the runs in question are in excess of 1000 feet as I used the full 1000 foot box plus about another 100+ feet.

Helpful Member!  wires (TechnicalUser)
6 Dec 07 12:28
650' is the number I have always used and it worked fine.

Over that length I have used twisted pair converters. On one job we went over a mile on a private buried phone cable.

You should be able to get the long runs working with a amplifier like these:

www.supercircuits.com/index.asp?PageAction=VIEWPROD&ProdID=4403
www.eclipsecctv.com/ECL-VPA_video_amplifier.html

It is always better to put the amp at the signal source (in this case the camera end) than to amplify noise at the other end of the circuit.


aarenot (Vendor) (OP)
6 Dec 07 13:23
wires,
     Thanks for your response!   SO you have always used 650' as the limit, and would not guarantee anyhting farther.    
     Thanks for the suggestion on the amp, I will pass that along to the contractor who subbed this out to me.   Since I was just contracted to run the supplied cable, on the determined path, I would think that equipment, and it's installation would have nothing to do with myself.   
     This was not my job, I was strictly sub-contracted to run the supplied cable on the specified path, and make some BNC connections, and some 18/2 connections.   These units were not in my scope of work, so I will leave that up to them.

Helpful Member!  ttech (Vendor)
6 Dec 07 18:41
We has a project where placing the power transformers closer to the cameras fixed poor quality issues
aarenot (Vendor) (OP)
6 Dec 07 22:11
ttech,
     Thanks for your reply as well!   I will pass that along to the contractor as well.

     The contractor specified the location of all of the power supplies in my scope documents so re-placing theses would not be part of my scope of work, but their problem.  

     I wonder how long you have been able to, and would gauarantee RG59 runs though.

wires (TechnicalUser)
6 Dec 07 22:47
"Let me know what you think.   I did inform the customer of their underestimate of lengths prior to running the cables, so they were aware."

I think you did your job.

The fact the system does not work properly appears to be the fault of the the person who designed the job. Unless they can document or demonstrate that their design works then I would assume the problem is theirs.

I would not let this fact stand in the way of extra work for you. Obviously they didn't know what they were doing and now you have the opportunity to step in and be the hero, for a fee of course.


"We has a project where placing the power transformers closer to the cameras fixed poor quality issues"

A simple voltmeter check will tell you is there is a voltage drop problem. Connect a voltmeter to the power conductors at the camera end with it on and read the voltage. If it is not within 5-10% of spec then problems are likely.

If the power cable in aarenot's post is over 1000' then there is likely substantial voltage drop in addition to signal attenuation problems.

No electrical device works properly with under voltage!

You can use a variable output power supply on the bench to demonstrate a voltage drop problem. Simply dial down the voltage and watch the picture degrade.

While not the best solution using a higher voltage power supply can get the desired voltage to the camera even after the voltage drop over the power cable. Be careful if you use this solution and NEVER exceed the maximum voltage rating of the camera.
aarenot (Vendor) (OP)
6 Dec 07 23:03
Thanks again wires, I appreciate yout insight.   I am not so sure I want to continue to work in this less than knowledgable contractor situation.   Not knowing the lengths of the cable runs on a job they bid, not knowing they were over length spec for RG59, and still using RG59 as well as many project management, and materials delays makes me unsure of the competency of the contractor, which lends to the kind of hassles that exceed the worth of the jobs.

Even I know you can use higher grade coax cable or even UTP for longer lengths, and I am no CCTV expert like a security company shold be.   

wires (TechnicalUser)
6 Dec 07 23:30
I just noticed that you posted that the power cable was 18AWG and apparently the cameras are 24 volt.

If the cameras draw 250mA the voltage drop at 1000' is about 3.3 volts, a 13.7% drop.

You could test a camera an see if runs on 20.7 volts but I have my doubts.

To sum up are two issues:

1. Attenuation of the video signal traveling down the coax. The solution is a video amp.

2. Voltage drop. Kudos to ttech for bring that up. I didn't even think of it in my original reply. The solution is larger wire, local power for the cameras, or a higher voltage power supply for the long runs.

For example, if the run is 1100' of 18AWG and the camera draws 250mA then a 28 volt power supply will yield about 24.4 volts at the camera. Likely well within the camera's specs.


Good luck!
wires (TechnicalUser)
6 Dec 07 23:42
"I am no CCTV expert"

Check out supercircuits.com their staff is more than happy to solve any problems you may have with a CCTV job. Very knowledgeable, VERY helpful and good prices!


"the kind of hassles that exceed the worth of the jobs"

Charge the piss out of them with a hefty up front payment!

If they agree then laugh all the way to the bank. If not watch the them get very small in the rear view mirror...
brianinms (MIS)
6 Dec 07 23:51
My only comment is, who in the world is still using coax cameras this day in age ... haha.
aarenot (Vendor) (OP)
7 Dec 07 9:26
I did not recieve the power supplies until after the cable was pretty much already run so I did not even know what the supplies voltages would be.  I had already told them the runs were much longer than they had anticipated, so they were informed prior even though it is not my issue since I did not design the system.   

I am simply going to tell them that since the cable run exceeds the rated distance for the RG59, as well as exceeds the rated distance for the 18/2, and I was simply contracted to run the cable, and did not design the system, performance is their issue not mine.  If they need anything else I will do it time and materials.

wires (TechnicalUser)
7 Dec 07 10:27
"My only comment is, who in the world is still using coax cameras this day in age ... haha."

Anyone looking at cost and quality.

Composite video outputs on most all CCTV cameras in current production are designed to use coax. Converting to twisted pair will always lower quality while costing more because of the baluns.

IP cameras cost much more and the run length is restricted to 330'. They also have to be powered so unless they are POE some wire has to be run. While convenient IP cameras don't have the video processing capabilities of some higher end DVRs.

The parts cost for a coax 4 camera, quad and monitor system is under $200. There is NO WAY to beat that with any other technology.
SYQUEST (TechnicalUser)
8 Dec 07 0:49
My 2 cents, the capability of the RG59 would depend on the manufacturer's specifications for the given type and application.

Did the contractor provide the the proper RG59 cable types for this application? (for example: outdoor use, not in conduit or other protection)

I like the way you kept the client up-to-date with these types of conditions. It always pays to be honest with the client.

In a way I am not surprised that this contractor would run the job this way. From what I have seen for installations of both alarms and video security over the years, have been far worse than some of the worst phone system installations I have come across.

But I trust you have been able to use your expertise to a good advantage.

....JIM....
brianinms (MIS)
8 Dec 07 4:04

"Composite video outputs on most all CCTV cameras in current production are designed to use coax. Converting to twisted pair will always lower quality while costing more because of the baluns.

IP cameras cost much more and the run length is restricted to 330'. They also have to be powered so unless they are POE some wire has to be run. While convenient IP cameras don't have the video processing capabilities of some higher end DVRs.

The parts cost for a coax 4 camera, quad and monitor system is under $200. There is NO WAY to beat that with any other technology."


I didn't imply the use of baluns, however I have worked on the networks of 5 casinos and they all use IP based cameras. All of them record to DVRs as well as display in real time on a console cluster as desired.

In addition if you design a network that has more than 300 ft between IDFs has serious issues.
aarenot (Vendor) (OP)
8 Dec 07 9:28
SYQUEST,
      Thanks for yours, and everyones responses.   The cable type provided is listed above in the subject, the application is indoor with no conduit.   The cameras are outdoor rated, but are mounted directly to the walls so the hole in the wall is covered by the camera, thus not exposing the cable to the elements.   The cable is a pretty simple set up, with really only the distances being unusual.   
      The security companies tech who is dealing with the head end equipment, connecting at the power supplies, and final aim/focus of cameras has said the manaufacturers stated limit is 750 feet.   He has been doing this for 12 years, and seems knowledgable, and also my research has shown that 1000 feet is over the limit, so 1100+ feet is not even close.
     My intent in regard to performance will be to tell the security company that if they are testing the camera at over 750 feet from the head unit that the results are invalid, and they will need to provide any remedy themselves.   If they wish to do a test which I would support providing any remedy myself were it to fail, it would have to be with the camera no greater than 750 feet from the head unit.
    If they put an amp in the middle, that creates a second cable run out of the single run which I was contracted to provide, and therefore it is again their issue to deal with.   Since I was paid a set rate for 33 single runs, those runs are supported up to 750 feet by myself.   If they put an amp  at 750 feet, that essentially ends the run I was paid to install prior to the amp.   Beyond that 750 feet, and beyond that amp is in reality now an additional cable run which I was not contracted to provide.  If they would have proposed the amps in the first place I would have considered those additional runs after the amps, and charged for another run.   I was contracted to pull the cable make Two BNC crimps, and connect the power cable, and coax at the camera end.  That includes no amps, no additional crimps, no barrels, no amp installation or connections.   
     Maybe I am being a stickler here, but they have been nothing but a pain making me wait over two weeks for cable then it is a fire drill when the cable arrives, as well as not providing the crimps until the day before the proposed project deadline.   So I am not cutting them any slack, any more.

GMgerry (Programmer)
10 Dec 07 9:29
It looks like you have plenty of info to resolve the cabling issue. My comment is that who hired you to install the cable is fully responsable for the project. They supplied the design, engineering, material and scope of work for the project. They are responsabile to the customer and you for any additional labor, material or engineering for the project.

Ask them to provide they engineering documentation that supports the design.
tnlcom (TechnicalUser)
11 Dec 07 14:52
Hi Aarenot,

Just for the record, if you did not supply any of the materials and the contractor told you what equipment was being supplied and installed where and when, the only person that is responsible is the Contractor not you. your job is to install the cable and equipment and report back any problems when doing so and not to resolve issues of poor design. The contractor should resolve these issues with the client and explain what you need to do for him to resolve the issues.

Sounds to me like someone is trying to buck pass the ownership of a poorly designed system.

All of the problems mentioned can be resolved but they need to explain this to the csutomer and resolve any cost implications and overuns as a result and instruct you if they intend you to finish the project what remedies are required to resolve the problem.

If I employed someone to install a CCTV system on my companies behalf I would not be blaming them if I spec'd it out incorrectly.

I beleive from contractual point of view, you have fullfilled your job, even if the result is the system has faults that are not of your making.

Hope that helps!
aarenot (Vendor) (OP)
11 Dec 07 16:22
Thanks tnl for your response.   I try to do my work as unto someone more powerful, and influential than a customer.   Therefore I try to get a second opinion when I get in these situations where someone seems to expect more than they paid for, in this case way more.   

Nothing wrong with checking yourself once in a while to see if what you are feeling is reasonable, and it seems I was nto far off.   

Your statement about if you contracted someone, what you would , and would not expect said it just the way I needed to hear it.  

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