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100 M CAT5 Cable Length No Signal 1

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compuspec

Programmer
Jan 30, 2003
3
US
Hi All,

I've tried cabling a warehouse with a distance of 90-100 meters away from my Hub/Switch but unfortunately the signal drop up to 60-70 meters only. I thought UTP Cable can extend a signal of up to 100 meters as what I heard from cable and hub manufacturers but apparently not.
I am using an AMP CAT5E UTP cable and 16 PORTS D-LINK SWITCH

Please give us your comment on this.

Regards
Boboy

 
Is it possible you have a bad port on the D-Link switch or a bad patch cord?

The 100 meters includes patch cords. You say "no signal", does that mean no link or very low transmission or bandwidth?

....JIM....
 
make sure you are going from a patch panel to a jack to factory patch cord's and don't crimp plugs directly on the end of the cable

don't make your own patch cords out of scrap

any sharp bends or kinks in the cable ?

the 100mete4rs assumes proper cable practices

I have run a lot at the 100 meter and had no issues





 
Check your connections... make sure the pins are pushed all the way to the tip of the connector. You should be able to see them if you look at the end of it.
 
You have a connection issue. I have run Cat 5e for 200m@100MHz with no problems.
 
Hi Guys,

Thanks for your reply.

The 100 meters cable when i tested were not installed yet and is still rolled in circle.

I have wasted 6 plugs and repeatedly crimped 3 times on both ends and i'm sure i follow strictly the color coding but still no link activity and the link light in the hub does not light.

I did not use a patch panel yet and I plugged directly 1 end to the hub and another end directly to the pc.

When I cut down the length to 60 meters, there goes the link.

What do you think is wrong?
 
What do you think is wrong?

crimping plugs on to start with

terminate it properly ,

to jacks and patch panel

use factory made patch cords
 
Something happened in those last 40 meters. You probably skinned the cable or someone ran over your floor coil with a forklift while you weren't looking.

I go crazy when my guys start stepping on wire. Stepping on it won't sever the cable or make the signal go dry, but it absolutely can affect performance.

There is some very inexpensive "off-shore" CAT5e that's labeled as 350Mhz but priced at less than $80 a box. It's clearly NOT the cable it claims to be (they'll print anything on the box without recourse if it's not made in this country). Anyway, that's a long way of asking if you purchased a low grade cable, because I've heard of this stuff snapping inside the jacket when pulled a little harder than usual.
 
When you refer to 60 and 100 meters, are these differant cables? It looks to be a bad cable and nothing to do with your termanations. But I agree you need to do it properly even if you just use a jack at both ends a nd patch patch.

If your going to take time to do it...do it right.
 
Could be using stranded plugs on solid cable. Maybe you just got lucky the last time. Wiggle the ends and you'll probably lose the link on the "good" one too. As said already, use jacks or patch panel and patch cords. Crimped plugs will work (with the right plugs and tool for the specific cable) but is not standards based or good practice.

-CL
 
Something no one else has said. 100 meters of cable, when tested will measure more than 100 meters. The reason for this is the twists in the cable. We always TRY and limit our runs to about 90m.
 
Something no one else has said. 100 meters of cable, when tested will measure more than 100 meters. The reason for this is the twists in the cable. We always TRY and limit our runs to about 90m.

the standard takes the twist into consideration so will the tester

it is however 100 meters INCLUDING patch cords so by keeping your runs to 90 meters your allowing for 10 meters of patch cord to stay within standard
 
I don't think the problem is that he exceeded the standards. Even if he had, it wouldn't be a deal-breaker, nor would it explain why he had a "signal drop" suddenly at the 60 meter point.

To me, the "drop" suggests that his reflectometer found a wire break. That's why I asked about cheap cable and forklifts.
 
>What do you think is wrong?

There are only 6 things that could be wrong:

1. Bad connections.
2. Bad cable.
3. Bad hub/switch.
4. Bad NIC in the computer.
5. Electrical issues.
6. Interference.


Less than spec performance with any or all of these could cause the problem you are describing. With simple troubleshooting you replace one thing at a time with known good parts until the problem goes away.

I would start with the connections and cable. Get a known good 100m cable (with ends) and be sure the hub/switch and NIC work with it. If it still doesn't work substitute a known good battery powered laptop for the PC. Still no go? Get a hub/switch that runs off a external power supply to replace that part along with the laptop these will eliminate ground loops. Finally if it still doesn't work try everything in a different location to eliminate interference. Until you get a working system it is hard to figure out what is wrong.

Most problems are found in field assembled parts like jacks and plugs. Since apparently you are new to crimping plugs that would appear to be most likely point of failure. Installing plugs is not difficult but unless you have the correct parts and install them correctly they cause lots of problems.

BE SURE the plugs have the same wire colors in the same positions on both ends! You probably have this right because you get link at 60m.

BE SURE one pair terminates on pins 1&2 (green or orange pair) and another on pins 3&6 (the pair not on 1&2). The other pairs should terminate on pins 4&5 (blue pair) and 7&8 (brown pair). Pins are read from left to right with the contacts up and away from you. If you "split pairs" it won't work at 100m.

You might want to find a professional in your area to check your cable. If you are real nice and offer money or beer you might even get it checked on a cable scanner!

Good Luck!
 
Definately a pinout/connectivity issue. A cheap customer once had us run 1500' of I/W Cat 5 outside a building, over the roof, splice in the middle of the roof, and run 500' more to tie two buildings together. It worked great for 2 years until the rain corroded the splice! Ha ha ha ha ha!
 
Dagwood nailed it.
"I don't think the problem is that he exceeded the standards. Even if he had, it wouldn't be a deal-breaker, nor would it explain why he had a "signal drop" suddenly at the 60 meter point."

Cut the cable at 60 feet and reterminate it. I bet it works then. Sounds like a shiner on a pair or even a break!
 
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