Can't figure this out.

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After carefully running CAT7 cable from 2nd floor to basement thru stud bays and finished ceilings etc., I put RJ45s on each end, one end to my computer through a POE switch and the other to a Hikvision bullet 8MP camera. The camera's startup lights lit up alright but I couldn't get a picture on my computer's browser using the default IP address.

I hooked up a tester to the one end ofthe CAT7 run with a remote on the other end to test the cable. It indicated all 8 wires "fail," and that they were "open." Presumably the tester's signal was not connecting to the remote. It didn't indicate a short or crossed wires or that the wires were improperly installed in the RJ45s.

Being that it seemed, (judging by the startup lights on the camera) that it was receiving power, I further tested the cable by hooking up the tester and sending an audible signal independently one at a time through each of the 8 wires. The tester sent the audible signal through each wire independently from one end to the other through the cable's total length. I received the audible signal at the other end independently for each of the 8 wires.

I retested the camera though the CAT7 run, but it still did not work. The tester still indicated "fail" and "open." Then I plugged the camera directly into the POE switch and was able to get its image from my computer.

At my wits end.
 

fenderman

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What exact cable are you using? Did you use the 568b standard?
 
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I used Sunnytech CAT7 ....the pairs are shielded with foil. Yes I used the 568B...Redid each end when I found I couldn't see the camera on-line, just to be sure. When I did the audible signal test each wire corresponded in the right order on the opposite ends.
 

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I should add...I have 2 other cameras installed with the same wire with no problem. I'm able to monitor them. I of course unplug them from the POE switch when testing the one I'm having trouble with, so as not to be using the same default IP address. I planned to change the IP addresses after installing and testing the lot.
 

ctgoldwing

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. . . I further tested the cable by hooking up the tester and sending an audible signal independently one at a time through each of the 8 wires. The tester sent the audible signal through each wire independently from one end to the other through the cable's total length. I received the audible signal at the other end independently for each of the 8 wires.
This test doesn't tell you if a pair is shorted. If you check continuity between each wire and all the others you can confirm that one or more is shorted or all are ok. There are testing devices that do this but an ohmmeter works.
 
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The only thing with that is.... (incomprehensibly) that if there'd been a short along the CAT7 cable's length, I shouldn't have been able to receive the audible signal independently on each wire. I'm certain without a doubt that there was no audible signal coming from the other 7 wires each time I received the signal through one. A short would have the signal coming in on more than the one wire, or at least not through the wire matching the exact sequence (which was the case) of the one at the sending end. I know...this is ridiculous. But in absence of any significant finding on my end, I may have to get a technician to attend my place to look at it. To have to run another wire to replace this one is a nightmarish thought. I'll mention using an ohmmeter but I'm too inexperienced to interpret what I'd find using one myself. Thanks for your thoughts on this.
 

alastairstevenson

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Can you do a close-up image of the connector at each end of the cable such that the wire colours can be seen?
 

weigle2

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I should add...I have 2 other cameras installed with the same wire with no problem. I'm able to monitor them. I of course unplug them from the POE switch when testing the one I'm having trouble with, so as not to be using the same default IP address. I planned to change the IP addresses after installing and testing the lot.
Why are you not bench setting these up before you install them? Always change the default IP address to something other than the default. You will avoid alot of problems by making sure it's set up properly before installing it.
 
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Why are you not bench setting these up before you install them? Always change the default IP address to something other than the default. You will avoid alot of problems by making sure it's set up properly before installing it.
True enough. As you may have determined I'm an amateur with this stuff. I know enough not to confound the process with conflicting IPs so instead of changing the defaults right away, which is itself something I need to study up a bit on, I just unplugged the other cams I'd previously tested successfully connected to their respective CAT7 runs. As I mentioned I was able to get a picture from the camera I'd intended to connect to the CAT7 run that I'm having trouble with, using a short cable plugged into my POE switch. I will of course plan resolve the IP conflicts before hooking the whole business up to my NVR.
 
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This would be a good place to check :)
I did examine both ends with magnifying glasses, finding no anomalies.
Can you do a close-up image of the connector at each end of the cable such that the wire colours can be seen?
I also cut off and discarded the original RJ45s on this run, and very carefully changed both ends, (568B) ending up with exactly the same situation. Being that I've had success with 3 other cameras undergoing the same processes, the situation completely confounds me.
 
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