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rg59 max distance

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Hey all,

 

I know this has been asked before but there seems to be multiple answers so I need to ask again.

 

What is the general rule for max cable run for RG59 coax???

 

My search is inconclusive.

 

Thanks much.

 

Les

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Most experts say 750 ft.

 

 

Thanks, I have found that but have found reference to 200 -250 and 500. If it is 750 I am good to go since I am looking at 275'.

 

Now I have to look at the voltage drop issue.

 

Thanks again.

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275 ft. is no problem if you use proper RG-59. Make certain you get high-quality RG-59 with 100% pure copper center conductor and at least 95% braided copper shield. Do not use CATV cable, which uses clad center conductor (copper-coated steel) and aluminum shield.

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275 ft. is no problem if you use proper RG-59. Make certain you get high-quality RG-59 with 100% pure copper center conductor and at least 95% braided copper shield. Do not use CATV cable, which uses clad center conductor (copper-coated steel) and aluminum shield.

 

 

Thanks, most of my runs to date have been less than 150-175 foot runs. So now I am looking at almost twice that and don't want to shoot myself in the foot.

 

Thanks for the input.

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what do we need to avoid when running the cables? to avoid hum bars?

That's hard to say since you never really know if you are going to have a ground loop issue. The best I can tell you is keep the cable as far away from power wires as possible and if you have to cross them, do it at a 90 degree angle. Also try to attach the cameras to non-conductive surfaces where possible.

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sir surtech in case the signal cables run parallel with the power lines, how far should the separation of this two wires to avoid any interference?

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1 foot minium

1ft Minimum or I've went as far as actually suspending the cable in the air away from the wire that most electricians have laying on top of the ceiling tiles.

 

How do others on the forum combat the "Ground Loop" issue on their end?

 

Thanks,

John

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I usually try to suspend my runs above the ceiling tile and away from most electrical conduit or runs, that way the electricians did not have me to blame for any of their problems, LOL.

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1 foot minium

1ft Minimum or I've went as far as actually suspending the cable in the air away from the wire that most electricians have laying on top of the ceiling tiles.

 

How do others on the forum combat the "Ground Loop" issue on their end?

 

Thanks,

John

 

Surprisingly with over 900 cameras, we have never had a ground loop issue in the casino. That is probably due to our using Pelco CM9760-MDA's on all inputs. Thay have isolated input connectors (no common ground).

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I usually try to suspend my runs above the ceiling tile and away from most electrical conduit or runs, that way the electricians did not have me to blame for any of their problems, LOL.

 

I blamed them once or twice until I got into a ceiling that they were doing the suspension of the wire and I was like so I had to take a different approach and routed my cable differently and worked great.

 

CM9760-MDA... Ouch... those are pricey , not all of my customers are wanting to drop that kinda cash.

 

Thanks,

John

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I usually try to suspend my runs above the ceiling tile and away from most electrical conduit or runs, that way the electricians did not have me to blame for any of their problems, LOL.

 

I blamed them once or twice until I got into a ceiling that they were doing the suspension of the wire and I was like so I had to take a different approach and routed my cable differently and worked great.

 

 

I'm embarrassed to say that around here it is usually the low voltage guys that are laying cable across the ceiling tiles.

 

I sure wish the vacuum guy would have called about this pipe. I would have liked to have moved that J-hook to the back side of that 2by. Now the cables are on the wrong side of the pipe.

95193_1.jpg

 

But, Yes. We go high and never have interference issues. But the extra cable sure adds up!

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sir is the cable not be prone to attacks from rodents? do we need to put the cable inside flexible hose? or suspending the cable above the ceiling would do?

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sir is the cable not be prone to attacks from rodents? do we need to put the cable inside flexible hose? or suspending the cable above the ceiling would do?

 

I think it depends on your location. Around here the only time I have had rodent problems is when the cable penetrates an exterior wall or floor. They seem to be chewing their way into the building more then anything else. I have never had rodent issues with suspended cable.

 

As far as having to run cable in conduit; That would be a question for your "local authority having jurisdiction". Around here we do not have to use conduit. But personally I am very particular about using proper fire wall penetrators and using plenum rated cable where needed.

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thanks. because i had a experience before that the rat chewed the power supply lines. what type of cable do you use for power? is it also plenum rated?

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I need some advice on a solution. I have a client that needs a camera situated approximately 1100 feet from the DVR head-end. No doubt the signal will attenuate long before then. It is an outdoor camera location with a trenched line that leads back to a stable (approximately 300 ft from the camera with 120V receptacles available within), the line would then be relayed the remainder of the length to the head-end.

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I have a bunch of cameras that are over 1,000 feet away. UTP cable with a passive balun at the camera, and an active balun at the head end. Works great.

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I have a bunch of cameras that are over 1,000 feet away. UTP cable with a passive balun at the camera, and an active balun at the head end. Works great.

 

Thanks for the input... what do you do about the power? Every balun I have come across limits the power to ~300 feet.

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There are two options:

1. Get power from nearest source

2. Run separate ac power line from your cctv room if you eant it centralized

 

Running dc 12volts is not advisable due to the voltage drop that will occur

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I have a bunch of cameras that are over 1,000 feet away. UTP cable with a passive balun at the camera, and an active balun at the head end. Works great.

 

Thanks for the input... what do you do about the power? Every balun I have come across limits the power to ~300 feet.

 

I use a siamese cable that has a seperate 16/2 for power. For power purposes, almost nothing is more than ~300 feet from a closet/panel. The UTP gets routed through multi-pair trunks back to the head-end (which can be well over 1,000 feet)

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Hey all,

 

I know this has been asked before but there seems to be multiple answers so I need to ask again.

 

What is the general rule for max cable run for RG59 coax???

 

My search is inconclusive.

 

Thanks much.

 

Les

 

 

There is no simple answer for this but the rule of thumb is 250m for RG59u. This is for pure copper , 95% braided shielding & 0.9mm centre conductor. But there are other things that may impact on that. The 1 vpp composite signal level is only a nominal level & not all cameras will have that output , some will be lower. A black/white composite signal will generally be around 4.7Mhz while a colour will be around 5.5Mhz. Thus the colour signal will have ever so slightly more attenuation. (not a lot but may be important over max runs - read on ) After the coax the most important item is the DVR I/P circuitry. All DVR inputs will have signal/noise discrimination circuitry. This is the bit that determines if bona fide video signal is present or if it is just noise. There is a threshold that if not reached the DVR will determine there is video loss and respond accordingly. This level is determined by the received sync level , the white signal level and the colour burst (chroma + luma ) level of the received composite signal.

 

Generally it is accepted that with "quality cable" the following maximun distances are used-

RG59u (7.9 db /m @ 50 Mhz) 250 m

RG6u (4.9 db/m @ 50 Mhz) 350m

RG11u (4.3 db/m @ 50 Mhz) 500m

 

Keep in mind that the physical size of the cable increases as the performance increases & can be a problem in itself. For longer distances there are a number of techniques that can be used such as amplifiers , equalisers & compression devices if the buget allows for them.

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sir surtech in case the signal cables run parallel with the power lines, how far should the separation of this two wires to avoid any interference?

 

The induced noise (hum) will be dependant on the EMR of the field surrounding the powered cable & this is dependant on the current in that cable. So for a cable supplying a 60W light globe you could run parallel for quite some distance with no ill effect while for a 415 v 200A welder circuit you would want it as far away as possible. The quality of your components (DVR , coax etc) also comes into play.

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