Ethernet cable problem

[Marauder2003]

I have a strange problem.

Long ago I had some Ethernet cable run from the house to the garage. I installed keystone jacks on both ends. Cable is stamped 4PR 24 AWG U1P CMX CAT5E 350 MHz OUTDOOR DIRECT BURIAL. The cable goes up an interior wall to attic, into a PVC pipe to the garage and out into open air in the garage. The pipe also contains a telephone line and some TV coax cable. In the garage a home made Ethernet cable running from an IP camera is plugged into the keystone jack on the cable from the house. In the house a commercial Ethernet cable goes from the keystone jack to my switch. I have a perfect image from the camera.

Decided I wanted to go PoE. Got a couple of PoE cameras and a PoE switch. Installed one camera using the cable type mentioned below. It works fine. PoE light is on on the switch and I have picture.

Now working on garage cam. Plug cam into garage jack. Moved cord in the house from regular switch to PoE switch. No PoE light on the switch. Camera not functioning. Disconnected everything from CMX cable and attached a CompuCable transmitter/receiver tester to cable. Lights cycle correctly but they are very dim. I have a cord I made that is twice as long as the CMX made out of cable labeled E171480 VERIFIED (UL) CM OR MP. CAT 5e TO TIA/EIA-568A 24AWG 4UTP C(UL) 0898FT 2001. The tester lights are very bright when test is run. Run the cable from the PoE switch to the garage camera. PoE light comes on and camera works.


Any idea what is the deal on the CMX cable and PoE? I also replaced the keystone jacks with new ones that use punchdown technology. No joy.

[Skip_Dog]

Make sure both ends are correctly punched. I would re punch one end and test. If no joy re punch other end. I have run into this problem before. Test light works and even data transfer works. POE did not until I saw that one pair was not punched correctly and had a small cut in it. Must have been the POE pair. Good luck.

[d33pt]

also get rid of any self crimped patch cables. the problem may be there too, if your punchdowns are good.

[ExtremeX]

You probably have line loss over distance... How long is the run and what voltage POE?

If everything was terminated correctly, you might be looking at voltage drop issues when using POE under load, which is probably why its tests fine. Meaning its a power issue, and not a data communications issue...

If you have a DMM, test the voltage of the PoE pair on the other end of the run.

If its a confirmed power issue... You could consider using 22AWG cat6 cable to decrease voltage drop and increase current handling, or a separate POE injector closer to the device.

[FresnoRob]

You probably have line loss over distance... How long is the run and what voltage POE?

If everything was terminated correctly, you might be looking at voltage drop issues when using POE under load, which is probably why its tests fine. Meaning its a power issue, and not a data communications issue...

If you have a DMM, test the voltage of the PoE pair on the other end of the run.

If its a confirmed power issue... You could consider using 22AWG cat6 cable to decrease voltage drop and increase current handling, or a separate POE injector closer to the device.

This was also my guess reading your post.

[Marauder2003]

Problem run is 40 ft. The other cam I mentioned has a run of 65 feet with a different kind of cable. No problem.

Pin 1/2 and 3/6 on good run (self crimped both ends) measures 47 volts. With no cam attached it measures less than 1 volt.

On the bad cable it measures less than 1 volt no matter if cam is attached or not. If I plug cam into switch with a short commercial cable it measures 47 volts. So cam and switch port are good.

I have another way to get cable from garage to switch so I will make a run with the other kind of cable.

[Marauder2003]

Well, ran 45 ft of the grey E171480 VERIFIED (UL) CM OR MP. CAT 5e TO TIA/EIA-568A 24AWG 4UTP C(UL) 0898FT 2001 cable using the structure beams between garage and house. Crimped an EZ Jack plug on the switch end and a Cable Matters KJ8 Cat.6 keystone jack in the garage. Tester showed all wires connected correctly and the lights were bright. Connected camera and plugged cable into PoE switch. Picture!!

I am having some electrical work done and will have the black CMX cable removed from the pipe and some of the grey run instead. I will inspect the old CMX cable very carefully. Having it out of the pipe I will be able to check resistance/continuity of each of the 8 wires.

[cfm117]

Verify continuity on all pairs. Strap tip and ring of each color on one end (ie solid blue and striped blue, etc) and test to see if you can see the shorts between each of those to verify good continuity on the other end. Digital multimeter should prob give and a loop resistance of 1-2ohms or so if it's just regular 22-26awg telco. It's a basic test we do testing pairs in the field on Ma Bell cables

[CandG]

If the run is only 40ft, sometimes replacement is more efficient than troubleshooting.

[Marauder2003]

If the run is only 40ft, sometimes replacement is more efficient than troubleshooting.

I gots to know. Did I use all 8 wires or just 7.

[Satex]

Ethernet and POE should work fine to nearly 300 ft so the 40 ft run you have isn't an issue. My guess is that the cable to jack terminations are poor. Redo both and retry.

[Brutmor]

Is the cable labeled 'CCA' or copper clad aluminum?

[Marauder2003]

Ethernet and POE should work fine to nearly 300 ft so the 40 ft run you have isn't an issue. My guess is that the cable to jack terminations are poor. Redo both and retry.

Done, twice.

[Marauder2003]

Is the cable labeled 'CCA' or copper clad aluminum?

No. 4PR 24 AWG U1P CMX CAT5E 350 MHz OUTDOOR DIRECT BURIAL

[Dubious_Beans]

Are you sure they are wired right?
It's not enough that the wires have continuity from end to end. (pin 1 to pin 1, pin 2 to pin 2, etc.)
They need to have the right colors attached to the right pins to make sure the twisted pairs don't get "split up" or it will not work corectly.

You should verify, double verify, triple verify that the right colors really do go to the right pins on each end according to the diagram below.



This way is OK too, but not as popular as 568b shown above