UTP vs. STP

[Kevin]

I have Cat5e wire running in a pipe that is also carrying electric. I was hoping Home Depot would have STP but they didn't so we ran the UTP for the hell of it. Should I even connect the UTP to the keystone jacks or should I just order some STP online?

 

[spidey07]

STP is not used in network applications.

You'll be fine with properly installed UTP

 

[Kevin]

The thing is the UTP cabling is run right next to the power lines in the same conduit. I'm thinking there may be EMI from the power lines.

 

[spidey07]

you'll be fine unless it is 400 volt.

 

[Kevin]

Nah, 20a, 125v

 

[spidey07]

you'll be fine and within specification.

Worse thing you could do is install STP. It is very difficult to install properly, isn't supported by ethernet and what you wind up with is a cabling system that is nothing more than one huge antenna sucking in any and all frequencies of EM and delivering that to your NICs/switces.

 

[cmetz]

Kevin, "STP" typically refers to a kind of cable with a different characteristic impedance from EIA cat5, which was used by IBM's Token Ring, and is not Ethernet compatible. There is such a thing as shielded cat5, it's expensive, and if improperly installed it will make the noise worse.

One of the reasons why cat5 twisted pair Ethernet is so popular is that it's very forgiving. I would strongly urge you to avoid power as best you can, and where you can't, either be parallel or perpendicular to it, not at funny angles. While being near power isn't great, it often just can't be avoided.

Incidentally, cat6 cable might help your noise rejection, and be a lot cheaper than shielded cat5e.

>The thing is the UTP cabling is run right next to the power lines in the same conduit. I'm thinking there may be EMI from the power lines.

Whoa there! This does not comply with the NEC. Thank you for playing. You just failed your electrical inspection. (well, you would here, where they're pretty strict) You are not permitted to run low voltage and current carrying cables in the same conduit.

Forget about noise on the line - this violates electrical safety.

 

[Kevin]

I needed a dedicated electrical outlet in my bedroom and there was no easy or feasible way to get it snaking through the house so we ran piping on the side of the house from the basement to the second floor. Since I don't have a cat5 hookup in my room I figured I'd run a cable in that pipe as well. The wires are together for roughly 15 feet in the pipe then seperate.

 

[EatSpam]

Originally posted by: Kevin
I needed a dedicated electrical outlet in my bedroom and there was no easy or feasible way to get it snaking through the house so we ran piping on the side of the house from the basement to the second floor. Since I don't have a cat5 hookup in my room I figured I'd run a cable in that pipe as well. The wires are together for roughly 15 feet in the pipe then seperate.

Why'd you need a seperate outlet in your bedroom?

 

[Kevin]

LOL. I want a window A/C for the summer since the central air isn't cutting it. The room gets very hot in the summer, especially when I have my PC and Laptop running.

 

[cmetz]

Kevin, please hire a licensed electrician.

 

[Kevin]

I did. He did all the electrical and I put the cat5 through.

 

[skyking]

Pull it back out of there and route it differently.

Kevin, "STP" typically refers to a kind of cable with a different characteristic impedance from EIA cat5, which was used by IBM's Token Ring, and is not Ethernet compatible. There is such a thing as shielded cat5, it's expensive, and if improperly installed it will make the noise worse.

One of our business partners wants to make a dozen drops from the demarc closet over to the datacenter, and wants to use shielded. I am trying to talk him out of it, but if not, will I be OK of I join the drains and ground them to the bonding system at each end?

 

[Kevin]

There's no other route. In another room I was able to follow the central air straight to the basement but in this room the central air doesn't go straight down so there is no way to route the wire.

 

[spidey07]

I agree with hiring a professionl at this point or speaking with your insurance agent on coverage for out of code (state dependant) installation.

If you have somebody else install it then it is their problem, not yours.

 

[randal]

Originally posted by: Kevin
There's no other route. In another room I was able to follow the central air straight to the basement but in this room the central air doesn't go straight down so there is no way to route the wire.

Yay wireless!

 

[ScottMac]

Given that "there is no other route" - then the UTP should be run in another conduit parallel to the existing electircal pipe.

Modern transceivers and cable technology negate most common mode noise; the narrow conduit is more likely to have a negative effect on your cable's transmission characteristics than the 60Hz hum.

The issue is one of safety. Running the UTP that close is putting an additional voltage on your network cabling (which can mess up your PC) and, if "something" happens that causes the electrical cabling to short to the utp, your PC (and possibly you) are toast.

Plus, you mention that the electrical is for an air conditioner .... a notorious noise & pulse source. The system can handle a little hum, but the starting kick and motor noise from the AC is likely to seriously mess with your data, and probably your NIC .... maybe even the PC ... depending on other factors.

I gotta believe that any "electrician" that would put high and low voltage cabling in the same (probably 3/4") pipe would also skimp in other areas ..... I'd be very nervous.

If that's the only path, then run another pipe.
(or better yet, as suggested, go with wireless)

Good Luck

Scott

 

[spyordie007]

Originally posted by: spidey07
I agree with hiring a professionl at this point or speaking with your insurance agent on coverage for out of code (state dependant) installation.

If you have somebody else install it then it is their problem, not yours.

I agree, saving a few dollars is not worth the risk

Yay wireless!

No kidding

 

[Kevin]

Wireless is lossy. When I had cable it wasn't noticeable but with Fios you really feel the burn.

A licensed electrician did the electrical install. I just followed what he put and ran the cat5.

 

[Rapidskies]

Can't you just drill through the floor to the basement and run the cat5 cable seperately?

 

[Kevin]

The basement is 2 floors down. Below this room is the kitchen. If it was on the first floor I would have just followed an air vent but this room is basically impossible to get to from anywhere in the house.

The issue is one of safety. Running the UTP that close is putting an additional voltage on your network cabling (which can mess up your PC) and, if "something" happens that causes the electrical cabling to short to the utp, your PC (and possibly you) are toast.

Wouldn't the surge protector avoid that? (My UPS has ports for RJ45)

 

[spyordie007]

A licensed electrician did the electrical install. I just followed what he put and ran the cat5.

Obviously it's too late now; but I would have tried to get him to stick in a second conduit alongside his for future use.

Whenever I have conduit going in I always try and put at least one spare (empty). It's only a matter of time before I want to run something else...

 

[spyordie007]

Wouldn't the surge protector avoid that? (My UPS has ports for RJ45)

A surge protector will definetly help to reduce the risk that something would happen to your machine. On the other hand it wouldnt help the other issues that can occur as the result of a short, i.e. a fire

 

[Kevin]

OK, you guy's can sleep tonight, we're going to run another conduit parallel to the existing one in the next few days.

 

[spyordie007]

perfect

:thumbsup: