twisted pair or RG

[outrider]

I've got an application where I have an outbuilding about 300 feet from the main house. The CCTV cameras are run to the main house on twisted pair cable with baluns. ( the cable is not shielded and is in conduit)

The problem being after every storm cameras disappear. I would have favored RG cable over twisted pair as it is easier to protect, but I am getting conflicting information.

Any ideas as to what/why I am having these problems?

Thanks in advance

 

[hbiss]

Re: twisted pair or RG

The problem being after every storm cameras disappear.

By that do you mean that the cameras are damaged by lightning? If so I don't think it makes any difference what they are connected with, it's all in how you protect them.

-Hal

 

[outrider]

Re: twisted pair or RG

No not lightning.

Any storm be it rain or otherwise. I don't think that twisted pair is ideal for this situation but I cannot find anything to tell me differently. The cable is not grounded. And the previous company installed lightning protection but did not use it. I installed lightning protection and it seems to be working. I should say I am losing the picture, as the cameras seem to be undamaged and I can get a picture locally.

I suppose the issue is this. IS cat5 the best wire for this application? Underground, 300 feet, unshielded.

Thanks

 

[hbiss]

Re: twisted pair or RG

I should say that I prefer RG-59 for this but that's only because I'm old school. It shouldn't make any difference which you use as long as it's installed properly.

I suspect that you are having moisture or water ingress problems with the UTP and that's probably because the usual indoor PVC jacketed cable was pulled through the conduit. Just as there is flooded RG-59 available for underground use there is also a direct burial CAT5 UTP.

-Hal

 

[outrider]

Re: twisted pair or RG

It is direct burial cable. I would prefer RG59 too but I am old school too.

I'm not knocking UTP, it is just not as forgiving in exteme environments.

THanks for your help.

 

[don_resqcapt19]

Re: twisted pair or RG

If I had a real choice, I would use fiber. I just don't like signal wiring that runs between two buildings. I know, in many cases this option is not cost effective.
Don

 

[hbiss]

Re: twisted pair or RG

I know it's not direct burial but anything in conduit and buried in the ground should be considered the same. Probably even worse because the conduit will fill with water and the cable will be constantly submerged. Direct burial at least will be dry at some times.

-Hal

 

[sparky_magoo]

Re: twisted pair or RG

For 300 feet, I would run at least RG-6U. The loss on RG59-U would be unacceptable. When using UTP, I consider the loss and distortion through baluns to be unacceptable.

 

[KyawaComm]

Re: twisted pair or RG

I would use RG6

 

[jlmiller]

Re: twisted pair or RG

I've done this and a company named Polyphaser makes some real good surge protection devices that work well if properly grounded.

 

[tom baker]

Re: twisted pair or RG

Fiber is not that expensive anymore. Quality convertors from fiber to eternet cost about $50.
A recent article in cabling installation magazine stated coax for cameras is on the way out, the trend is to cat 5 or wiring.

 

[dereckbc]

Re: twisted pair or RG

Really doesn't make any difference whether you use Cat 5, RG-59, or RG-6 on a video camera CCTV. The frequency of the camera isn't high enough to make a bit of discernable difference to the receiver at 300 feet. Nor does it make a bit of difference in terms of lightning?protection, all are equally venerable and the protection schemes are the same.

I also side with Tom on using optical cable. It eliminates all technical problems associated with copper facilities, and the price is becoming competitive.

I would also concur that the problem is probable water permutation if you have eliminated lightning or power problems (attenuates the signal below minimum thresholds of the receiver). It is the only thing left. So the solution is pretty straight forward, run a new transport media in a water tight raceway, or overhead with a cable suitable for the purpose.