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Balun haters gonna hate...

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realistic and proven.

 

Thats not bad at all. How about interference from other cables? Sometimes there is no choice and I have to pull cable close to 230VAC cables for several meters. In an old Warehouse, I have several cat5 cables in a conduit together with all kinds of other cable for at least 150 m - I don't even know what these other cables are, but I am sure some also run high voltage. I wonder what system is protected better against this type of interference.

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Thats not bad at all. How about interference from other cables? Sometimes there is no choice and I have to pull cable close to 230VAC cables for several meters. In an old Warehouse, I have several cat5 cables in a conduit together with all kinds of other cable for at least 150 m - I don't even know what these other cables are, but I am sure some also run high voltage. I wonder what system is protected better against this type of interference.

Should keep coax at least 1 feet from high voltage, so yes interference is a concern.

BTW 1500' would be RG6, 1800' with RG11 (depends on the brand of cable).

RG59 is less, maybe 750?

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Should keep coax at least 1 feet from high voltage, so yes interference is a concern.

BTW 1500' would be RG6, 1800' with RG11 (depends on the brand of cable).

RG59 is less, maybe 750?

 

BTW at those kind of distances, its a better idea to just run a big multipair and then branch of from that with coax or cat5. Then you have extra cables left over incase they want to add more cameras later. I would amplify any cable over 750' anyway, and keep all cables away from high voltage.

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Should keep coax at least 1 feet from high voltage, so yes interference is a concern.

BTW 1500' would be RG6, 1800' with RG11 (depends on the brand of cable).

RG59 is less, maybe 750?

 

BTW at those kind of distances, its a better idea to just run a big multipair and then branch of from that with coax or cat5. Then you have extra cables left over incase they want to add more cameras later. I would amplify any cable over 750' anyway, and keep all cables away from high voltage.

 

Yeah, I didn't really have that choice of keeping it away from the other cables in that Warehouse. It went well though and there was no loss in picture quality. What do you use to amplify the camera signal?

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I checked our price guides, 1000' of plenum rj59u + 1000' of 2 conductor 18awg is around $100 more than 1000' of cat5e.

 

 

the big difference maker is the extra 18awg cable.

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Baluns definately have uses and I use them frequently. On small installs they don't always make sense.

That depends somewhat... as I've noted before, we almost never use coax for ANYTHING... it means having to stock and cart around two more types of cables (RG-59, and station wire for power). I have a box of coax that's been sitting in my garage for about 14 months now, I've been using it so little. I have two boxes of Cat5e in my van that get replenished every three months or one large install, whichever comes first.

 

One downside of baluns is the ground loop problem. This happens on many poorly planned installs that use baluns. The simplest way to avoid that is to use separate power supplies for each camera.

This is not a downside of baluns so much as it is a downside of cheap 12V cameras that have a shared power and video ground. Use dual-voltage or AC-only cameras (in other words, something with an internal regulator that separates the video and power grounds), and you don't have this problem, regardless of whether you use 12VDC or 24VAC.

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This is not a downside of baluns so much as it is a downside of cheap 12V cameras that have a shared power and video ground. Use dual-voltage or AC-only cameras (in other words, something with an internal regulator that separates the video and power grounds), and you don't have this problem, regardless of whether you use 12VDC or 24VAC.

 

True, but it is also true that it doesn't happen when you use coax instead. In my experiance also brand cameras use a common ground sometimes, especially IR cameras and dome cameras.

 

I prefer to use separate PSU instead of limiting myself to cameras that have dual voltage.

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This is not a downside of baluns so much as it is a downside of cheap 12V cameras that have a shared power and video ground. Use dual-voltage or AC-only cameras (in other words, something with an internal regulator that separates the video and power grounds), and you don't have this problem, regardless of whether you use 12VDC or 24VAC.

 

True, but it is also true that it doesn't happen when you use coax instead.

Actually, the same POTENTIAL for the problem exists. The issue lies in the fact that you end up with two substantially-different-length-and-resistance ground paths to the same point (since the balun inserts a long coil of wire in the video ground and signal lines). If you had substantially different ground paths using coax/power, you'd have the same issue. Although granted, that's not likely to happen in most installs, the ROOT of the problem still lies in the cameras having a shared power and video ground.

 

In my experiance also brand cameras use a common ground sometimes, especially IR cameras and dome cameras.

Yes, and those will have the same potential for the problem.

 

I prefer to use separate PSU instead of limiting myself to cameras that have dual voltage.

Separate power supplies are great until you get more than about 6 cameras and fill up your power bar. Go to 8+ cameras, and it starts to get very messy.

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Yeah, I didn't really have that choice of keeping it away from the other cables in that Warehouse. It went well though and there was no loss in picture quality. What do you use to amplify the camera signal?

 

Active UTP/Baluns with UTP cable, or coax amplifiers with coax, but I never had the need myself.

 

We do what we do to get the job done .. I understand clients doesnt want to spend a fortune running all new conduit so sometimes have to make do. Glad it worked out well

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I checked our price guides, 1000' of plenum rj59u + 1000' of 2 conductor 18awg is around $100 more than 1000' of cat5e.

 

 

the big difference maker is the extra 18awg cable.

I would have thought the big difference is that is plenum and likely the most expensive cable one could buy.

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Soundy will love this one, quoting a 76 camera job with UTP transmission.

Quoting it both ways, whichever is cheapest and less labour intensive, wins.

Although 17 are scattered in separate buildings in different locations with their own DVRs and will be coax as only very short runs.

 

And oh yeah, gotta love those 32 channel DVRs for only $991 retail

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One downside of baluns is the ground loop problem. This happens on many poorly planned installs that use baluns. The simplest way to avoid that is to use separate power supplies for each camera.
This is not a downside of baluns so much as it is a downside of cheap 12V cameras that have a shared power and video ground. Use dual-voltage or AC-only cameras (in other words, something with an internal regulator that separates the video and power grounds), and you don't have this problem, regardless of whether you use 12VDC or 24VAC.

 

Once I installed a dedicated PS with had it's own ground, I started having ground loops problem. The problem was only when using the cheap original camera cable which have the shared power and video ground. No ground loop if using cat5 with separate wires for video and power. Solved with the 3 to 2 prong adapter for the PS.

 

Bought quality cat6 from amazon 1000' for $135.

Edited by Guest

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Baluns definately have uses and I use them frequently. On small installs they don't always make sense.

That depends somewhat... as I've noted before, we almost never use coax for ANYTHING... it means having to stock and cart around two more types of cables (RG-59, and station wire for power). I have a box of coax that's been sitting in my garage for about 14 months now, I've been using it so little. I have two boxes of Cat5e in my van that get replenished every three months or one large install, whichever comes first.

 

I have to agree with soundy here, cat5 allows me to carry 1 box of wire, I can run video and power over cat5, yes rg-59 has power with it but then I am stuck running my power in the same direction as the video cable. Much easier to use cat5 and go in a different direction with power if needed. I to have a about 400ft of rg-59 which I have been sitting on for close to a year now that I cant get rid of, will probably just end up using it myself for toying around with personal builds.

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yes rg-59 has power with it but then I am stuck running my power in the same direction as the video cable. Much easier to use cat5 and go in a different direction with power if needed. I to have a about 400ft of rg-59 which I have been sitting on for close to a year now that I cant get rid of, will probably just end up using it myself for toying around with personal builds.

RG59 is just video cable. It has no power with it unless you buy Siamese.

If you want to go in a different direction with the power (dont know why though?), you could use RG59 and just run 18awg for power, in any direction you like.

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