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sistemasjg

Cabling Termination at DVR/PC side

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Hi, after about 2 years doing maintenance for some cctv installations I´m just begin installing cctv systems from the beginning. I´ve finalized a 36 cams system for a big condo and other 2 installations of 16 cams each one in a chain of stores. The experience has been cool and nice. But the problem or what I don´t like is the cable mess at dvr end, I mean, all cables coming from cameras and the power adapters (I´ve to use them because here nobody sells independent isolated power supplies and all the cameras are the cheap 12v common ground ones). I´ve tried putting all inside a 40x30cm metal box but the Geovision card cables are too short to get inside the box.

 

So, my questions to you are:

 

How do you terminate nicely yours installations at DVR/Geovision side?

 

Ps. Im using cat5e cable with baluns, running one cable for each camera.

 

Thanx in advance and excuse my english. I´m from Venezuela

Edited by Guest

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thats a tough one. tbh honest i never use cat5 to cable with. rg59 all the way on new installed because the quality of signal tends to be better plus it has the correct ohm termination. i would try and use a box to tidy the wires as much as possible and spiral bind as much as possible to keep it all contained

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There are a number of options depending on the types of baluns you're using. Some allow you to terminate the cable in an RG45 plug and then provide BNC and power out on a pair of tails. Some are screw or punch terminals with a 2-3" BNC tail; others have the BNC right on the body. I've used the "tailed" type terminating in a metal box on the wall immediately behind the DVR, with the tails hanging out the bottom and connecting there with the breakout cables (Vigil DVR, but they're essentially the same cables as the Geo).

 

You could buy or make a number of short (2-3') BNC cables to extend the runs so you can terminate inside a box.

 

I've sometimes dropped all the runs right at the DVR and just left the baluns hanging there, then split off the power pairs and slipped some split-loom around the power pairs to lead them off to the power supply. I've done vise-versa as well. All depends on what the specific installation calls for.

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That´s what I call a quick and complete answer

 

There are a number of options depending on the types of baluns you're using. Some allow you to terminate the cable in an RG45 plug and then provide BNC and power out on a pair of tails. Some are screw or punch terminals with a 2-3" BNC tail; others have the BNC right on the body. I've used the "tailed" type terminating in a metal box on the wall immediately behind the DVR, with the tails hanging out the bottom and connecting there with the breakout cables (Vigil DVR, but they're essentially the same cables as the Geo).

I´ve been using this http://www.bikudo.com/photo_stock/4000.jpg and this http://rygelcomputer.com/images/balun3.bmp but never think on using the ones with the tails, I just asking my provider to ship the tails ones.

 

You could buy or make a number of short (2-3') BNC cables to extend the runs so you can terminate inside a box.

A great idea too, perfect for the 4in1 balun

 

I've sometimes dropped all the runs right at the DVR and just left the baluns hanging there, then split off the power pairs and slipped some split-loom around the power pairs to lead them off to the power supply. I've done vise-versa as well. All depends on what the specific installation calls for.

Yes, that is true, but you know, chances are than someone comes and see the cables hanging and criticize, making the customer think if there are other ways of doing it.

 

Another thing is driving me crazy is, what is the maximum distance two cameras must be separated to use just one cat5e cable, I mean, using one pair for video on camera A, other pair for video for camera B and, one pair for power + and the other for power -? In the condo job, I use 1 cable for each floor, 2 cameras per floor. One at the elevator exit and the other in the emergency stairs. The cable comes from a duct in the middle of the floor and then split for each camera. This two cameras shares a 1A 12v power wart. The image in the security office at lobby are crystal clear for each floor. The distance from the power supply and each camera is quite different but here is no problem with wavy images, no ground loop.

 

In other installation, I tried to do the same thing, even the cameras are more close to each others, about 1 or 2 meters, and it was a complete disaster, all cameras have interference. I rerun just 1 cable for each one and the problem disappear. Then, just for testing, I tried to share power for two cameras close to each other and the problem rise again.

 

What I want to avoid is to have 16 power supplies inside of a box or hanging. This work is done after a shop makeover or remodelation, and the previous cctv installation using coaxial and the same 16 cameras were using just 4 1A 12V power supplies.

 

Thanks for you quick answer and I hope no to be too long in my post

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You could buy or make a number of short (2-3') BNC cables to extend the runs so you can terminate inside a box.

A great idea too, perfect for the 4in1 balun

You'd pretty much have to use short "jumper" cables for that, yeah.

 

I've sometimes dropped all the runs right at the DVR and just left the baluns hanging there, then split off the power pairs and slipped some split-loom around the power pairs to lead them off to the power supply. I've done vise-versa as well. All depends on what the specific installation calls for.

Yes, that is true, but you know, chances are than someone comes and see the cables hanging and criticize, making the customer think if there are other ways of doing it.

 

Heh, that will happen no matter what you do. Make the cleanest, most perfect, tight, smooth, seamless install possible, and someone will still come along and say, "Yeah, it looks great, BUT I woulda done it like this..."

 

There are only two ways to deal with that: listen to them and get more ideas for next time, or just ignore them. It's like the old joke, "How many lead guitarists does it take to change a lightbulb? Seven - one to do it, the other six to sit around saying how they could've done it with more FEELING."

 

Another thing is driving me crazy is, what is the maximum distance two cameras must be separated to use just one cat5e cable, I mean, using one pair for video on camera A, other pair for video for camera B and, one pair for power + and the other for power -? In the condo job, I use 1 cable for each floor, 2 cameras per floor. One at the elevator exit and the other in the emergency stairs. The cable comes from a duct in the middle of the floor and then split for each camera. This two cameras shares a 1A 12v power wart. The image in the security office at lobby are crystal clear for each floor. The distance from the power supply and each camera is quite different but here is no problem with wavy images, no ground loop.

 

In other installation, I tried to do the same thing, even the cameras are more close to each others, about 1 or 2 meters, and it was a complete disaster, all cameras have interference. I rerun just 1 cable for each one and the problem disappear. Then, just for testing, I tried to share power for two cameras close to each other and the problem rise again.

 

Sounds like a classic case of ground loops through the baluns. It's not a factor of the power supplies or the distances involved, but of the design of the cameras: when the cameras have a shared power and video ground, you have one ground on the camera following two separate paths. With only one camera on one power adapter it's not a problem as the power ground doesn't reference to anything at the adapter end. When you connect two or more cameras to the same power ground, though (whether spliced together on a wall wart, or tied together on a common ground rail on a central power can), each camera's ground then has two paths to the DVR's ground. The baluns introduce a transformer winding into the video ground at each end, which adds dozens or hundreds of feet of length, as well as some resistance.

 

The way to avoid it, short of individual wall warts for each camera, is to use 24VAC cameras, or dual-power cameras that have internal regulators, which effectively isolate the video ground from the power ground.

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The way to avoid it, short of individual wall warts for each camera, is to use 24VAC cameras, or dual-power cameras that have internal regulators, which effectively isolate the video ground from the power ground.

 

Altronix also makes some Isolated power supplies. Not always available nor cheap though. I used one once. eg. ALTV2416ULI3

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The way to avoid it, short of individual wall warts for each camera, is to use 24VAC cameras, or dual-power cameras that have internal regulators, which effectively isolate the video ground from the power ground.

 

Today I just finished a 13 cam new job, just for test I plug 4 cameras (singe dome, non IR) on one 1A wall wart. All perfect, no problems at all. The same cable brand, the same baluns, just the cameras are different, but are cheap 12v Chinese common ground too.

Finally for the 13 cameras, I installed 5 warts, for safe.

 

Altronix also makes some Isolated power supplies. Not always available nor cheap though. I used one once. eg. ALTV2416ULI3

Yes I've read about Altronix a lot in this forum, but unfortunately nobody sells this brand here. No to mention that here the dollar exchange is in control by the government , so is a real PITA to get US$ for imports.

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The way to avoid it, short of individual wall warts for each camera, is to use 24VAC cameras, or dual-power cameras that have internal regulators, which effectively isolate the video ground from the power ground.

 

Today I just finished a 13 cam new job, just for test I plug 4 cameras (singe dome, non IR) on one 1A wall wart. All perfect, no problems at all. The same cable brand, the same baluns, just the cameras are different, but are cheap 12v Chinese common ground too.'

I have seen instances where it hasn't caused problems, this is true... but most often, it does, at least from my experience.

 

Altronix also makes some Isolated power supplies. Not always available nor cheap though. I used one once. eg. ALTV2416ULI3

Yes I've read about Altronix a lot in this forum, but unfortunately nobody sells this brand here. No to mention that here the dollar exchange is in control by the government , so is a real PITA to get US$ for imports.

If anyone here can sympathize with you on that, it'll be Rory!

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If anyone here can sympathize with you on that, it'll be Rory!

LOL thats right, we have to import it here also, average 1-3 weeks delivery

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Sometimes we use 24Vac Master power supply, and for any camera that is not dual-voltage we use a 24v to 12vDC power converters at the camera end. Though that can get expensive.

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Hi everyone, newbie around here.

 

There are "cable wraps" that might help a lot to divide and organize cables. Also I usually try to identify each cable (you never know when something is gonna fail, but usually is pretty soon -murphys law-), so I save a lot of time later. I have noticed that when you invest time on tagging everything and avoid mess, things will be easier later and your work will look different.

 

Also, if power need for each channel is 1 Amp or less, it looks a lot better a Boxed CCTV PSU.

 

Problem is, as my friend SistemasJG have mentioned, is not so easy to find some things here in Venezuela. You have to struggle to get decent stuff. And usually you have to pay a lot for things that are kinda cheap on USA, UK, Western Europe, Asia...minimum wage here is just two cheap chinese cameras...

 

I would like to see pictures of other peoples work (specially 16+ cameras work) to see good ideas.

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