atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring When to use shielded Cat 5-6

Anyone know of any info or standards on when shielded cable MUST be used? or is it a "when in doubt" use it issue. I've searched around a bit and came up short.
Is a dedicated metal conduit sufficient to eliminate EMI if shielded cable is'nt used?
What is a safe distance away from EMI using unshielded? I know around fluorescent lights its 1 to 2 ft., but what about distance around megavolts?

If a radio or TV tower is staight overhead causing RFI that would be the application. EMI can be easily eliminated by placing cable 12" from fluorescent lights. Megavolts? Is this being used in the vicinity of welders or high inductance or what. Straight voltage should not create EMI. Sheilded cable is usually not necessary at all, is very expensive, and requires the use of special jacks to complete the shielding process. Search on Google for BICSI website to obtain specifics.

I recently did an install for a Dentists office. The wiring was pre-speced I just installed it, but I installed Cat6 shielded to each of the operatories where there was an X-ray machine. I'm really not sure whether the sheilding in the cable would do anything to x-ray. I couldn't find any info.

Corwyn

No it won't and X-rays wouldn't be a problem anyway. Also, you need to use shielded jacks and patch panels (those that are designed to terminate the shield) with shielded cable. What the hell good does it do if it's hanging in the air at either end?

So for two reasons some computer geek wasted a lot of somebodies money.

To answer the original question, you almost never use shielded in this country. Apparently it's a big thing in Europe but not here.

-Hal

No they had shielded jacks on both end.
What a pain to work with.

Corwyn

OH, PS

This was speced by BICSI

This was speced by BICSI

Well, there's your answer! Any time you get a Real Cool Data Dude involved...

-Hal

Just wanted to know when you MUST run Shielded.
Look's like I don't have to worry.....

Thank's guy's.

I'm a little late gettin in on this but someone mentioned running Cat5 around welders and it caught my eye. I work in the steel industry and have some CNC equipment that I am planning to connect to our network. One machine (Torch/Plasma Cutting Table) is connected to a PC in the shop office via fiber and that PC is then connected to our network via Cat5. I'd like to change this and either plug the fiber straight in to our switch via a converter or remove the fiber and run some sort of shielded cabling that will connect directly to our switch. In addition we have another machine that is subjected to welding arcs which are approximately 30'+ away, I am looking to connect this machine to the network also.

In a nut shell I guess I am asking a similiar question here, at what point do you NEED something beyond the normal Cat5 cabling but I'm also curious as to how you can test for the need or what the symptoms of interference are? We have PC's just 15' and 2 layers of sheet rock away from our Torch/Plasma machine and they have never had any problems so it makes me wonder just how much of a problem it really is and/or if I can just swap out the Fiber for Copper and be done.

Any direction would be greatly appreciated!

That's really a difficult question to answer. Without test equipment to measure RF/EM noise levels, it would really just come down to experience and guesswork. You may want to run Cat5e and fiber. Doesn't cost much more to run fiber and leave it unterminated. If you don't have any problems with noise on the copper, great, you don't have to worry about terminating the fiber. If you do have noise problems, then the fiber is there waiting for you.

As for testing once you've connected, you can find freeware network diagnostic software to test for dropped packets, errors, delay, etc. At the very least you could leave a ping running for 30 minutes while the welders are being used, and check to see what percentage of packets are being dropped.

On another note, when a thread like this is already a few months old, it's best to start a new topic. New posts on old topics don't get as much attention as new topics.