TESTING CAT 6 CABLE TERMINATIONS

[mstrlucky74]

If you were only punching down one end and leaving a service loop on the other to be puched down by other but you wanted to test the cable how could you do so? WOuld you have to put a jack or something on the unterminated end? THanks.

 

[zbang]

How? Not very well. Without terminating the other end, about all you can do is check for major damage (shorts) and for the length of each lead (via TDR ping back from the unterminated end). If you have to test before the install is complete, and you'll have to test then, also, terminate each cable with a 8p modular plug (cheaper than the plate-mount jacks) and test.

Standard question- why?

 

[mstrlucky74]

How? Not very well. Without terminating the other end, about all you can do is check for major damage (shorts) and for the length of each lead (via TDR ping back from the unterminated end). If you have to test before the install is complete, and you'll have to test then, also, terminate each cable with a 8p modular plug (cheaper than the plate-mount jacks) and test.

Standard question- why?

Was curious as to how you would test if terms were by others but you explained....by using an 8P modular plug. Thanks.

 

[hbiss]

No, you really DON'T want to use a modular plug. It takes a great effort to reliably install them and your chances of screwing at least some of them up is nearly 100%. When that happens you won't know which end has the problem. If you must test, punch the ends down on jack inserts. At least those are semi-reuseable and you can see what you did. Better yet wait for the geek to install the patch panel then blame the problems on him. And he shouldn't be using plugs either.


-Hal

 

[Rampage_Rick]

A good tester like a Fluke DSP can test each of the 8 conductors from one end, which would reveal any poor connections on the terminated end, as well as some failures along the cable run. You'd still need to perform a full validation for things like crosstalk once the other end is terminated.

For example, if you had a 200' run, the DSP should indicate 200' on each of the pairs. A zero would indicate a poor termination, anything between zero and 200' (with a margin for error) would suggest something like a nicked cable. My DSP will fail the test if it sees mismatched pairs.

 

[Fulthrotl]

No, you really DON'T want to use a modular plug. It takes a great effort to reliably install them and your chances of screwing at least some of them up is nearly 100%. When that happens you won't know which end has the problem. If you must test, punch the ends down on jack inserts. At least those are semi-reuseable and you can see what you did. Better yet wait for the geek to install the patch panel then blame the problems on him. And he shouldn't be using plugs either.


-Hal

yup to all of that.

when i put in a data cable, i punch down to leviton cat 6 modular blocks on both ends, and certify the cable.
it's included in the price of the cable.

if the cable can't be put where it's final happy home is, and is coiled above the t bar, it still has a cable label on
it, and a jack, and is certified.

the short version is, "i'm done, pay me."

if you want me to do additional work on that cable, it's a relocation and recertification, at half the cost of a new cable.

simple.flat.rate.pricing.

and landing it into an 8 port rj-45 plug is not approved under the 802 standards, and it's like packing a marshmallow into a
piggy bank. try making a patch cord that certifies, and see how long it takes.

a leviton 6E+ jack is about $6.50, and i NEVER have problems with them. ever. i won't use anything else.

 

[zbang]

I think some of you are missing the point. The OP says "to be punched down by other", which tells me that any work they do is not final. As the terminations aren't final, all you can reasonably test for is short/open/ground. There is no point in looking for things line split pairs and crosstalk. Me? I'd pull the cable, leave both ends hanging and not test at all. If I had to do any testing before final termination, I'd use the cheapest ends I have because they're going to be cut off.

The other options is, as mentioned, to properly terminate both ends, do a full test, and charge for a full test. Also put in a disclaimer that the results are for your terminations, not those done by others. It sounds like this is out of scope for this project.

 

[mstrlucky74]

I think some of you are missing the point. The OP says "to be punched down by other", which tells me that any work they do is not final. As the terminations aren't final, all you can reasonably test for is short/open/ground. There is no point in looking for things line split pairs and crosstalk. Me? I'd pull the cable, leave both ends hanging and not test at all. If I had to do any testing before final termination, I'd use the cheapest ends I have because they're going to be cut off.

The other options is, as mentioned, to properly terminate both ends, do a full test, and charge for a full test. Also put in a disclaimer that the results are for your terminations, not those done by others. It sounds like this is out of scope for this project.

One end of the cable is being terminated in a controlller and that term is by other by I would like to still test the cable. My question is how is that done if that cable is being terminated by others. On the controller side I believe there will be no jack....just punchdown on some (block :? )on the controller.

 

[hbiss]

I think some of you are missing the point. The OP says "to be punched down by other", which tells me that any work they do is not final. As the terminations aren't final, all you can reasonably test for is short/open/ground. There is no point in looking for things line split pairs and crosstalk. Me? I'd pull the cable, leave both ends hanging and not test at all. If I had to do any testing before final termination, I'd use the cheapest ends I have because they're going to be cut off.

The other options is, as mentioned, to properly terminate both ends, do a full test, and charge for a full test. Also put in a disclaimer that the results are for your terminations, not those done by others. It sounds like this is out of scope for this project.

I didn't miss the point and I do agree with you.

One end of the cable is being terminated in a controlller and that term is by other by I would like to still test the cable. My question is how is that done if that cable is being terminated by others. On the controller side I believe there will be no jack....just punchdown on some (block :? )on the controller.

If neither end will be terminated on a jack to be honest with you I probably wouldn't even bother with testing because you are only running cable. 99% of problems are with the terminations. A wire map tester will show you nothing except problems with the terminations you installed for the test unless you were a real hack and caused opens or shorts. As long as you are certain that you haven't hacked up the cable, had kinks, knots or sharp bends etc. forget it. If they want actual certification which will show up those kinds of defects the only way you are going to do it is to terminate the cables with the proper category jacks on both ends. If you do that you will have to figure the cost of the jacks into the price even though they will get thrown away. And that will be nothing compared to the cost of a certifier.

-Hal

 

[mstrlucky74]

I didn't miss the point and I do agree with you.



If neither end will be terminated on a jack to be honest with you I probably wouldn't even bother with testing because you are only running cable. 99% of problems are with the terminations. A wire map tester will show you nothing except problems with the terminations you installed for the test unless you were a real hack and caused opens or shorts. As long as you are certain that you haven't hacked up the cable, had kinks, knots or sharp bends etc. forget it. If they want actual certification which will show up those kinds of defects the only way you are going to do it is to terminate the cables with the proper category jacks on both ends. If you do that you will have to figure the cost of the jacks into the price even though they will get thrown away. And that will be nothing compared to the cost of a certifier.

-Hal

Thanks Hbiss. So what's the difference between certification nd wire mapping. Are they both considered testing?

 

[zbang]

So what's the difference between certification and wire mapping. Are they both considered testing?

They're both testing, but you can think of it as the quality difference between a ohmmeter check to ground and a megger (or VLF) test. In this case, the wire map only tells you that pin 1 here goes to pin 1 at the other end and no where else. It doesn't tell you things like whether both ends are mis-wired the same way (split pair) or if the cable is kinked or damaged. Those probably won't affect DC but can very much affect 10g Ethernet. Proper cable certification tells you whether the cable and terminations will carry data at the design rate, and uses more expensive equipment and requires more training. Google for "cat6 certification" and poke around at the hits.

Hal- we're on the same page.

 

[hbiss]

Wire mapping testers check to see that the terminations on a run (jacks or plugs or patch panel) are wired properly and that there are no shorts between conductors or opens. It does not check for shorts to ground. It is your basic test that, after a run passes you can be sure a computer or other device connected to the jacks will work. Wire mapping testers can be had for around $100 to $250.


Cable certifiers and certification testing are much more complex. In addition to wire mapping they will test the cable and terminations to see if together they meet the category specifications for the cable you are using. Some customers require this certification to make sure the cabling was installed properly, that, for example, a CAT6 cable actually meets CAT6 specifications. If it doesn't it may not handle data at the maximum speed it was designed to. Many installation factors influence whether a cable will pass certification. Poorly installed termination, kinks, sharp bends, deformed cable, even using the wrong pulling lube can make you replace the run. Certifiers keep a log of all tests which can be downloaded or printed out and given to the customer as proof that every run in their installation passed. Cable certifiers are very expensive and have a learning curve so if you have a customer that requires certification and you don't do this all the time certifiers can be rented, however it makes more sense to sub it out. Some customers may want that anyway because they want an impartial third party to come in and certify your work.

My advice is that if a customer doesn't mention certification don't mention it either because it can turn into a can of worms. Careful installation of the cable and terminations with a wire map test will ensure that the network will work. Most customers will never notice any difference from certification.

-Hal

 

[mstrlucky74]

They're both testing, but you can think of it as the quality difference between a ohmmeter check to ground and a megger (or VLF) test. In this case, the wire map only tells you that pin 1 here goes to pin 1 at the other end and no where else. It doesn't tell you things like whether both ends are mis-wired the same way (split pair) or if the cable is kinked or damaged. Those probably won't affect DC but can very much affect 10g Ethernet. Proper cable certification tells you whether the cable and terminations will carry data at the design rate, and uses more expensive equipment and requires more training. Google for "cat6 certification" and poke around at the hits.

Hal- we're on the same page.

Thanks a lot