Cat5e Cable Length 487 feet 3

[mk81596]

We had some underground conduit installed and some cable ran to another one of our buildings. This was before my time and I new the length just looking at it was 350 plus. I terminated the cables at they were 487ft in length. I am going to uplink one and test it to check the network but I am guessing the latency will be terrible. Also I think standard cat5e cable was used and not the outdoor rated version(would like to know what that is called also). Should it have been the outdoor version. I am guessing that even though the plastic conduit is sealed that water will eventually get in there. Any suggestions

Thanks

 

[LkEErie]

Suggest what? Fiber? Direct burial Cat 5e? Slap your hands?

The numbers(letters) on my reel (Comscope) is Cat-5e OSP.

LkEErie

 

[mk81596]

Suggest whether or not that cable is going to be usable?
What the outdoor cat5e rated cable is called?
Is the standard cabling going to work in the plastic conduit?

 

[LkEErie]

1. The cable is usable. I would not expect stellar performance. 10 Base T will work on lamp cord.

2. Outside cable. Geeze that's what OSP is.

3. For a while.

 

[LkEErie]

To be fair, there are several options you could use. One would be fiber. Two would be a pair of modems. We use Megabit modems like MM-310/320F or 300. There are probably Short Haul Modem/ethernet solutions since lack of pairs isn't an issue.

Your inside wire cable could last anywhere from 1 day to 20 years. The very last time I did mine with a 25pair plenum wire it lasted from August to December, losing about 6 pairs a month.

I was not very happy pulling the correct cable in the dead of winter.

LkEErie

 

[mk81596]

Thanks Lkeerie for the replies. I am guessing the cable will work fine and might as well attempt to use it since it is already there. The bad thing is we still have to splice on another 30 feet to get to the idf in the building. Can you say cobble job!!!

 

[Tolson]

Can you say electrical problems just waiting to happen?

 

[oldtimerbob]

Cat5 should only be used for 300 ft max,no matter if it is OSP (Outside Plant)or no.
You would be better off using Fiber as suggested.

Has been in the cabling business for about twenty years and is now the Sr PM for a cabling company located in the Los Angeles area.

http://www.globusinc.net

Also a General Class Amatuer Radio Operator.

 

[wires]

There is more than one reason run fiber for this job.

First is length. I noticed in the original post the mention of latency. The difference in length will not make a perceptible difference in latency with the speed of light and all...

Second is electrical isolation. Fiber is non conductive so you won't need to fiddle with surge protection on each end.

Third is you have the wrong cable in place anyway. Most underground conduits will eventually get wet. Wet twisted pair does not work very well.


Good Luck!

 

[buitenhek]

Ran into same many years ago:
1. Due to varying building electrical ground float, PC's in one building were always having board problems (shorts & failures). You will have same, if not now, soon.
2. You should al least terminate on surge board in IDF/MDF but my guess Rube Goldberg is at play here so on a thunderstomy day, just disconnect the cable until threat clears. HA
3.Yes, ALL conduits will get water in them. Breakdown of PVC jacketed cable is slower than plenum. Time frame to failure-unknown..3 months..16 months..2 weeks. Try the test yourself.
4. Cable length latency issues will allow the user to start the computer in the morning and get some coffee in between keystrokes and enter key.
5. Walk away or suggest OSP fiber...like you know it should be.

Typical...spend $250K on computer equipment and software and run it on $1.95 worth of cable.
Sorry so negative, but this will not turn out happy.

Regards
Peter Buitenhek
ProfitDeveloper.com

 

[mk81596]

Wires-

What does the speed of light have anything to do with copper? There is existing cabling already in place before my time. I plan on running fiber anyway because of the limitations but just wanted to get some advice. You always have the old telcom guy say, "Ive run a network cable 1000ft and it worked just fine"!!

 

[dagwoodsystems]

I think wires was suggesting that latency over a 400 foot distance isn't a problem if fiber is used (which you are obviously aware). The data is propagated by visible light created with LEDs or laser, thus the speed of light remark. Electrons obviously do not flow this fast.

He also pointed out that fiber is impervious to electrical noise, which comes into greater play as the copper length increases.

Fiber is also available with a heavy OSP type jacket on it for outdoor or harse environments.

____________________________
Any sufficiently advanced technology is indistinguishable from Magix. --Arthur C. Clarke (imbellished).

 

[TDMtek]

Old Telcom guys still are living in the TDM World; at least the ones I Play cards with. Hook it up see what happens, (it wont work well if at all) good thing it wasn’t your call so that when it goes out or worse you can suggest a better solution.

The one suggestion on using modem at the end sounds interesting.

 

[wires]

What does the speed of light have anything to do with copper? "

For all practical purposes electricity moves at the speed of light. Therefore the extra 100+ feet in your cable run will have no effect on latency (discounting signaling errors).

Question - What is the speed of electricity, in the medium of small copper wires?
------------------------------------------------
The speed of a charged particle in copper is very slow: about 0.01 cm/s. At this rate, it takes about 3 hours for a charge to travel about one meter. The electric field (signal) travels at the speed of light through copper. The charge is not carrying the information, per se, but the information is transmitted by the electric field. It is like a molecule of water does not travel across the ocean, but the wave does.

http://www.newton.dep.anl.gov/askasci/phy99/phy99488.htm

Item one in buitenhek's post is part of what I was referring to about electrical isolation. When lightning strikes ground potential can be different by thousands of volts per meter. This puts the ground (supposed to be 0 volts) of one building much higher than the other. The result is lots of zapped boards. Surge suppression is not 100% effective in dealing with these and more common electrical system variations.

I'm glad you are planning on running OSP fiber. It will make the future brighter...

 

[mikeydidit]

From what you are seeing here the right way would be to install MM or SM fiber to your building. If the conduit was installed right, you could pull a small (around 12 strand) fiber to this and be done.

What you have on the ground now is a telephone cable to the building. It is refered to as PE, direct buried, jelly filled, and other names that I won't mention if you have ever cut your hands on the metal on the sheath. After recently pricing copper, I would be very suprised if you couldn't install fiber cheaper than copper and make this a good job instead of a patch that may not work.

Hell, there are no rules here - we're trying to accomplish something.
Thomas A. Edison

For the best response to a question, read faq690-6594

 

[LkEErie]

The phone company isn't the only one that can run ADSL

About 6 or 7 years ago, we had a customer who had 4 leased OPX lines to their plant which was a mile away from the office. We had PROCTOR 46224 loop extenders off a Mitel PBX feeding single extensions. Of course, in the span of 20 years, we have gone from serial data over single pairs (TELTONE DCS2) to some foreign MUX that did 5 voice lines over a single pair, to our present RAYCHEM 4 lines on one pair. When the Teltone died, and ethernet became easier, we went to Megabit Modem 310F/320F whick is 8K down and 1K up. Megabit modems are now up to 4xx and async speeds, but if you Google ADSL, you can easily find the same stuff the telco uses to deliver DSL to apartment complexes.

In year 2000 dollars, the Megabit Modem solution was about $700 the pair and the Raychem about $2000.

We may be one step behind the operating company in terms of technology, but the customer has paid for this many times over.

LkEErie

 

[PhoneGuy2000]

I am not sure why no one said anything, but if you are using this for data and you splice it, that will be introducing more problens. You will have to untwist the wires to pslice it and the splice itself creates an impedence mismatch. Use the fact that the wire needs to be spliced as a good reason to repull it. The 1st suggestion would be the fiber. Fiber or copper, you simply need an underground rated cable since it is not direct burial. You will be able to run data on a run that long but it won't pass a certification test and it will be slow. The network will experience retransmissions form packet failures which increases the aggregate traffic over that segment of the network.
By the way, any cable you buy has a rating on it called the NVP or nominal velocity of propogation. It is the comparison of the speed of the signal (electrons) as compared to the speed of light in a vaccum. A typical data cable has an NVP of 68 to 72. That meens the signal tavels at 70% the speed it would in a fiber.
I have used a commscope outdoor rated Cat5e cable and run a signal 600 feet and supported 10 base T with it. It would not link up at 100 Base T.

 

[Jtodd]

Couple different quick ideas....

1. for extending the cable...I'd consider using a 110 block to do the "splicing". Cost effective, and really not a lot different than a 710 splice, and probably more reliable than any type of "bean" splice.
2. If ethernet doesn't work, try point-to-point VDSL. Where using this on Cat3 OSP phone cable (some of which is 50+ years old) and are getting 5MB at 3500 feet. The specs say it's max. speed is 11MB and diminishes with distance 'til its gone at around 4300 feet. Works great for us. We're using the Zyxel Prestige 640 serise, about $250 per set.
3. As for replacing the cable, obviously fiber is the "proper" way to go this distance with any desirable speed (over 10MB). But also consider since it doesn't appear to be OSP cable, it is probably wet, and if some one use plenum cable, it might as well be a sponge. You may want to plan on replacing it because of water issue before you run into performance issues.

Justin

Justin T. Clausen
Physical Layer Implementation
California State University, Monterey Bay

 

[Sunrise05]

As you "Splice" this install a repeater or some othere electrical device that will regenerate and boost the signal. This will help in the short term. As numerous people have pointed out you would be better served installing a 6 or 12 strand fiber. This will eliminate latency issues and get you ready for the higher bandwidth the users will begin to demand in the future.

"Everything should be made as simple as possible, but not simpler

 

[AndyD5]

Only because I'm refreshing myself as to the standards so I may be prepared a little more I thought the ideal length not to exceed 295' from point to point allowing for about 12 adittional feet of patch cord at each end of a run. I would use Fiber for your application OSP (outside Plant)