RJ45 Test Tool

Hi Guys

We currently use the EZ-RJ45 crimp tool and and the EZ RJ45 connectors, fantastic tool as the EZ RJ45 type have holes for wires simple and easy etc

We use lan testers which allows testing at both ends of network cable, but sometimes its a real pain if the RJ45 colours are wrong when testing

Is their a tool that will test the RJ45 connector after you have fitted it on a single cable on one end only, just to prove that colours are all ok and RJ45 is correct as you fit the RJ45 plug

I'm confused. Isn't this tool known as "your eyes"?

The only way something like this would work is to have an alternative way to terminate the open end. This would just add another step. IMO you are just better off making sure the techs doing the work understand how the ends should be terminated. As above a visual inspection is enough to know if its terminated correctly. An experienced tech can usually see if an end is bad with a close inspection.

I really dont something like this as a time/labor saving method.

No because, you are testing the order of the wires not the color. so you need both ends done.

Technically true, but you should be using a 568a or 568b standard pin out, not just any random layout that matches on both ends.

Theoertically you could have some kind of magnifying tool that was able to detect colors,and tell you if the pin out was correct. The problem (IMO) is that if you really need such a tool, you shouldn't be doing rj-45 terminations.

Hello Craig:

I don't think there's a tool like this, and here's why:

Color Order Varies: There is nothing magical about the color of the stand vs. what it can be used for in a bundle. The color order 'standard' even varies into substandards! (TIA 568A vs B)

The bottom line: As long as an installer remains consistent, even a non-standard color order will technically work just fine. (Not advisable by any means, but true.)

Circuits Must Have Continuity: In order to check one end, both ends need to be connected. There are some very high-end cable certifiers that will tell you if particular strands are not making a connection or are botched up, but even those machines need both ends terminated to confirm electron flow is correct.

Checking both ends mean terminating them both, or your tech needs to be familiar with a toner probe to check bare strands, which usually takes more precision/skill than simply terminating the cable properly to begin with.

I'm not sure what LAN tester you have, but This checker is about $175 and tells you if pairs are crossed up:

If I were in your shoes, I'd get a device like this, and force my techs to terminate and check a bunch of 3' patch cables from a partial box of cable one day in between jobs. A 'rainy day' task, if you will.

Practice makes perfect. I think after an hour or two of crimping ends and checking them, they will be 'experts' in the field when it counts.

Hi Brian

Thanks for your info , I do know all this , i think i will issue everybody with a good quality magnifying glass, as I find its the best way to check the colours are correct on the J45 plug after crimping

Just wondered if their was a new magical tool on the market

Many Thanks

Brian, I disagree on a couple of points: While, yes, there will be pin-to-pin electrical continuity so long as the two ends match, the 'self-shielding from interference that the twist in the pairs brings it very important - at least in Pairs 2 & 3 (the orange & green, or green & orange), which are your transmit/receive data connections. The performance of the cable can be impacted if these pairs are not used as designed. Pairs 1 & 4 are usually involved in PoE and don't have the same signal delicacy that the data pair have.

Another key reason to stick to the standard is follow-on service. Anyone who make a change after the initial off-standard installation will be dumbfounded (and time-wasted) when faced with a unique pin-out 'personal style' of the original, lazy installer. Using the T568A or T568B style means a tech only has two options. There is some debate as to which is most-commonly used, though most IT Directors of larger systems ususally have a set-in-stone facility-wide requirement (this is partly to avoid the crazy confusion that would be introduced by a tech's personal 'style').

I've known the tester that confirms correct wiring as a 'wire mapper' - this one is $50, but practically disposable knock-off versions can be had for as little as $12 plus the cost of a 9v battery from any discount electronics shop). On the other hand, true certification meter like this Fluke instrument can set you back almost $10,000. It provides the documentation required for certified/lifetime warranteed installations.

Thanks Michael:

I didn't really consider the physical impact of twist order on performance, but I believe you raise a valid point.

However, I do think the point is a matter of optimization and doing things correctly for the best result, but not physical impossibility or the source of gross malfunction.

In my area, there are (former alarm now doing IP Video) installers that view their own non-standard wire order is an extension of personal 'flair' and it's the way they 'leave their signature' on certain jobs, ie:

Junior Tech: "What the crap is this?"

Lead Tech: "That order is Green Orange Brown Green-white (etc)? Oh, that's Joe-Bob over at Acme Security. He always does that, and leaves a twist of orange on the end."

I hate it, and am not defending it, but it's a real thing. As pissy as I might be about it, many customers don't care as long as the camera works well enough to his/her satisfaction.

So I'm in violent agreement with your second point!

"there are (former alarm now doing IP Video) installers that view their own non-standard wire order is an extension of personal 'flair'"

@Brian, @Michael: Forget colors, since electrons are not affected by them.

Here is the only thing you need to check to insure the cable will perform to spec.

Cable is wired straight thru on all pins, 1 to 1, 2 to 2, etc.


  • the strand for Pin 1 is twisted with the strand from Pin 2
  • the strand for Pin 3 is twisted with the strand from Pin 6
  • the strand for Pin 4 is twisted with the strand from Pin 5
  • the strand for Pin 7 is twisted with the strand from Pin 8

Thats it.

I don't understand how this is helpful.

Besides, there are plenty of specs that are very particular about color order, ie: TIA 568A & B.

Brian, sorry if I offended you, but your statement had to be addressed:

I didn't really consider the physical impact of twist order on performance, but I believe you raise a valid point. However, I do think the point is a matter of optimization and doing things correctly for the best result, but not physical impossibility or the source of gross malfunction.

As Michael pointed out end to end continuity is not enough. And it is not just a matter of 'optimization', but rather it is the whole point of twisted pair. If the pairs are not presented correctly to the Common Mode Rejection amp, your cable will work as good as one with no twists at all!

My post was only to clarify what the minimum electrical requirements of a cable need be to perform electrically to spec. Notice that T-568A and T-568B both meet my criteria, though other many non-standard schemes are not. My post was meant to show how to determine whether there is impact.

That is how it is helpful. Do you think I have said something factually incorrect, or what? And yes I meant only perform to the electrical spec, not the 'color' one.

No offense on my side. I think it is way oversimplistic to say 'Here is all you need' without recognizing there may be much more 'needed' to do a job to spec.

No offense on my side.

Good. This is what I meant:

Here is the only thing you need to check, with regards to the cable strand pin assignments, to insure the cable will perform to electrical spec.

The debate over color standardization vs the one over the wiring order of twist pairs are two seperate issues, and it makes it confusing to try and debate them both at the same time.

If we want to discuss non-standard termination schemes or any termination schemes for that matter, start a new thread. OP asked for help with a test tool, and the only replies I've seen here for the past 5 hours are off that topic.

Chris -

Of course electrons can't see color, but service techs can, and should pay attention - it's not there for decoration! The color coding is all about which-wire-is-which without testing or re-confirming from end to end. The color pairing standards are all about getting on the right page when walking into a job. Without that widely-held agreement, I might just *feel* like driving on the left side today, damn any others on my road :-)

I'm right there with you, don't worry.

In a strange coincidence I was talking with my brother in-law, (home automation contractor), last night who told me that he makes both his ends T-568A because that's what he was taught. (I think his first job must have been making cross-overs from straights)

And wasn't gonna change, no matter what I said. What can you do?

But if someone had a scheme that had OrangeWhite on 1 and Orange on 3, I would consider that just plain negligent, and do everything in my power to help them see that.

You'd be surprised how many folks look at you funny when you explain that when you use A-style on one end and B-style on the other, you get a cross-over cable. Which end is right, and which end is backward? Who knows ... then it starts to get religious

Both ends are correct, your purpose is to make a crossover cable, and that is what you get.

Both ends are using a TIA-spec pinout. If you wanted to turn it into a straight-through cable, you would cut one end off and re-crimp it in the same pattern as the remaining end.

We have used the RWC1000k. It isn't too expensive and is a nice middle road between an official certifier and a basic cable tester.

Not affiliated with them in any way, I just have one sitting on my desk and have used it successfully a number of times.

When I first started doing networking, I found and used the EZ-RJ45 system because I liked that the wires came through the connector making verification before crimping easier. I still use the crimper but at some point I didn't see the advantage anymore as I was paying more per connector than a standard 8P8C connector and I wasn't saving much time.

I mostly use a bright head lamp and verify the color scheme (I use 568 unless I need a crossover cable) and then slide the wires in the connector and verify again looking carefully through the clear plastic. A magnifying glass would be helpful if the tech's eyes are not very good. I still may make a mistake every now and then and need to re crimp a connector but will see that on a simple tester and have never needed to go past that.

I do know that at one time I had poor CAT cable from Home Depot where the colors would flake off the striped conductors and the solid conductors were very pale. This made termination painful. I'm not sure I finished using that box.

Electrons, are not color-blind after all. :) Theoretically, there might be a way for this tool to work on an electrical, not optical, level. Consider that to reduce crosstalk, the pairs are actually made with slightly different twist frequencies, like this cat 5 example:

A singly terminated and energized cable pair acts like a long capacitor and therefore will present a (ever so slightly) differing capacitance/reactance depending upon the turns per meter. Which could be used (relatively) to distinguish the pair from the others. Maybe some high-end tool does this already?

Why it might not be practical:

Detection of differing reactance too expensive for commercial tool

Possible varying - non-standardized TPM between manufacturers/categories of cable

The tool I linked must do something with this information. Its initial tests are done without the probe attached at the other end of the cable. Testing for shorts and cross talk and speed. Once that step is done it sends a tone so you can find the other end and then you attach the prob to finalize it.