DIY Network Mapping Tool




DISCLAIMER - Because, apparently, some users here (and elsewhere that I've linked this tutorial) think you don't have any common sense and it is necessary that I mother you: Label everything appropriately. Do not connect to a "live" network. This does not take the place of testing your cable runs.

This is a tutorial for creating a network mapping tool much like the one made and sold by (Shown Here), however it is super easy to make, costs a lot less, and improves on their design in three ways:

1.) The LED’s I used have a flat form factor which allows them to be encased in the indicator clips. Their design uses standard round LED’s which protrude making them susceptible to damage.

2.) This design incorporates an extra indicator LED in the power pack that lights up when a valid connection has been made at the patch panel, immediately alerting the operator at the jack of any potential failures. This can be useful if you are mapping a network by yourself and you will know that you will need to tone probe the connection. Usually this is due to improper wiring at the patch panel or the RJ45 jack.

3.) Their design does not have an RJ45 jack in the power pack, just a cable with a Cat5 connector on the end. Having the RJ45 jack as I have done allows you to quickly test your LED indicator clips by plugging them directly into the power pack. This is usefull when making the indicator clips and can also be useful when troubleshooting.

This tutorial assumes that the networks you wish to use this on are wired using the T568-B standard, but can be adapted for T568-A if necessary. It also assumes you possess basic knowledge of using the tools mentioned.

This tutorial does not cover construction of the project box/enclosure. I used some spare PVC parts and a network outlet faceplate that I had laying around. You could easily just use a single-gang outlet box/faceplate as the enclosure, but I wanted something with a little more spit and polish.

Make as many indicators as you need, and don’t forget to make extras/backups.

Step 1: Parts You Will Need

  • (100+)* flat red LED’s
  • (100+)* Cat5/Cat5e/Cat6 crimp connectors
  • (1) RJ45 Keystone Jack
  • (1) 3mm Red LED
  • (1) 9V Battery
  • (1) 9V Battery clip w/leads
  • (1) 220Ω resistor (¼ W)
  • Heatshrink tubing
  • Extra wires (I used some extra Cat5e wire strands)
  • Some sort of project box/enclosure.

*Obviously you can make as many (or as few) indicator clips as you'd like, I made 100 to start with.

Step 2: Tools You Will Need

  • 110 Punch-down tool
  • Crimp Tool
  • Soldering Iron
  • Pliers
  • Etc.

Step 3: Make the Power Pack (Step 1)

Shown is the schematic of the system we are making. The portion inside the blue dashed lines is the power pack.

Make the power pack first. This way, when you make the indicator clips, you can immediately test them by inserting them directly into the power pack.

Wire the RJ45 jack as shown.

  • Use a single wire to connect the orange/white, orange, green/white, blue terminals together. This will be the positive lead.
  • Use another wire to connect the blue/white, green, brown/white, brown terminals together. This will be the negative lead.
  • Depending on the type/brand of your RJ45 jack, your wiring may look different.

Essentially, what we are doing here is shorting the connections on each half of the 8-pin jack together, one side for positive, one side for negative. When making the LED indicator clips, it’s not always easy to get the LED leads positioned exactly where you want them in the connector, so doing this means your placement doesn’t have to be perfect. As long as each lead lands in one of the 4 slots on either side of the connector, you should be good.

Step 4: Make the Power Pack (Step 2)

  • Wire the negative lead of the RJ45 jack to the negative lead of the battery clip (black).
  • Wire the positive lead of the RJ45 jack to the negative (cathode) lead of the 3mm LED.
  • Wire one lead of the 220Ω resistor to the positive (anode) lead of the 3mm LED.
  • Wire the other lead of the 220Ω resistor to the positive lead of the battery clip (red).
  • Install this configuration in your project box however you see fit.

The 3mm LED needs to be mounted in the enclosure so it is visible to the operator. I used a 13/64 drill bit and some glue to mount mine directly next to the RJ45 jack.

There is no need for any sort of power switch. Simply unplug the power pack from the wall jack and the circuit is deactivated. Leaving it plugged in (or leaving an indicator clip plugged into it) can drain the battery.

Be sure to use heat-shrink tubing on all your connections to prevent shorts.

Also pictured are the pieces I used for my project box: A 1½" PVC coupler, A 1½" PVC plug, and a single-port faceplate. As I mentioned earlier, a simple solution would be to use a plastic single-gang outlet box with a faceplate, but I think this looks cooler.

Note: In the photo, you may notice that I wired the resistor to the negative lead of the RJ45 jack instead of the positive lead of the LED... it still works perfectly fine this way, I accidentally forgot to wire the resistor to the LED and didn't want to re-do the connections. I also don't want to re-write the steps, or re-draw the schematic, so do as I say, not as I do... or whatever.

Step 5: Make the Indicator Clips (Step 1)

The short lead of the LED’s are the negative (cathode) leads.

The negative leads also have a larger “flag” inside the LED body as shown.

Prep the leads of the LED’s as shown. The distance between the leads should be approximately 5/16”, and the overall length of the trimmed part should be about ¾".

Step 6: Make the Indicator Clips (Step2)

Insert the LED’s into the RJ45 ends as shown.

The negative (cathode) lead should go where the brown cat5 wire would normally go (far right).

The positive (anode) lead should go in the orange/white position (far left).

Again, since we shorted each half of the RJ45 jack of the power pack together, the left four slots will be positive and the right four slots will be negative, so positioning of the leads is not critical.

Crimp the connector with a crimping tool to secure the LED’s.

Make extras! They’re tiny and easy to lose, and if any of them stop working, you’ll be glad to have some backups on hand.

I’m going to experiment with adding some glue, epoxy, clear silicone, or RTV into the indicator LED’s for a little extra security… you should do the same, but remember that some glues will melt plastic, so don’t go all-in without testing a few first.

I tried using super glue, and it didn't work very well (took forever to dry and turned the clear plastic cloudy).

Step 7: Test the Clips!

Test each one by inserting it into the power pack’s RJ45 jack. Both LED’s should light up! If they don't, there's a problem.

It may be a good idea to periodically test all your indicator clips... It's easier to find the duds before a big job than during it.

Step 8: Using the Tool

When mapping a network installation, simply insert as many indicator clips as you need into the patch panel(s).

Using a short patch cable, attach the power pack to any RJ45 wall jack.

The corresponding indicator clip at the patch panel will light up and you will instantly know which panel/port number that wall jack is wired to.

Label and test everything accordingly!

Step 9: Troubleshooting

If the LED’s don’t light up, there is likely a wiring error made at the wall jack or at the patch panel.

If the indicator LED on the power pack doesn’t light up (but the indicator clip at the patch panel DOES), then there is likely a short in your power pack somewhere.

If the indicator LED on the power pack lights up (but the indicator clip at the patch panel DOES NOT), then there is likely a short in the cable run, the indicator clip at the patch panel, or the power pack.

When in doubt, you can always test an LED indicator clip by inserting it directly into the power pack.



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28 Discussions


7 weeks ago

Suitably banging my head off of any solid surface.....
Why didn't I look for a project like this when re-doing my network? I am now going to make this, strip off every label, pull out every plug, then use this project to label each cable properly!!
Ha Ha that will teach me to look for a brilliant instructable !!!

Outstanding Michael ! (don't you just love random posts like this!, yes I think my use of !!!'s is a symptom of a psychosis, probably because of having just ran so many network cables with ports and plugs at each run !!!!!)


3 years ago

This is awesome! The only issue I see is all the time I'd have to spend finding all the materials and making it and troubleshooting my tool before it's actually useful. Wouldn't it be easier and more cost effective just buying the tool from than spending all the time make it?

2 replies

Reply 12 months ago

Along with what Michael said, there is something joyful about making things yourself and really understanding why it works the way it works. So yeah, maybe it take a little more time, and might even cost more. =)

Probably, but I like making stuff, and as I outlined in the introduction, this is better than the one CableSupply sells for a couple reasons. Once I had everything, this took me about a day to make. There really wasn't any "troubleshooting" involved, it's a pretty simple design.


1 year ago

I just wanted to post a big thank you to Michael for making this tutorial. I'm new to the industry and was watching CableSupply videos for tips on structured cabling and came across the product advertised. I searched to see if there's anything else like this available for less and came across the tutorial.

So one improvement I made for myself is that it's dual standard. In North America the 568B is the more commonly used but I wanted to make sure that if i run into an A that I can easily use the tool nonetheless. The pictures are not of the finished product, this was more of a test phase. Essentially if you wanted dual standard just wire up one keystone as A and the other as B then connect the positive leads together and negative leads together and wire the circuit as you would in the diagram. I keep trying to attach pictures but it fails to upload or uploads one and not the others, so sorry for no pictures.

I saw a comment asking the cost. To be honest, I had a number of the components already so I spent $12 (Canadian mind you) on a bag of 100 LEDs and $7 on the project box, $5 on shrink wrap. If you were to get everything from scratch you're likely to spend as much as the tool from CableSupply cost however if you wanted to make the improvements in this tutorial you're better off to make it yourself. The website sells it (at the time of writing) the tool as a package for $65USD with 24 LEDs. If you needed more they want $50 per 24 more!!!! That's quite a bit of dough unless you wanted to make them yourself, I'm sure it's doable once you have the tool up close and see how they wired their RJ45s. I think another difference from what I can tell from the photos is that they fill their RJ45s with some sort of clear resin to seal it.

I buy ezCat5 connectors for $65 per 100 (Canadian mind you) so with that and the misc parts you're likely to spend quite a bit but you're also free to make the improvements. The status light definitely helps with a) finding dud RJ45s and b) just making sure the circuit is complete, you'll still want to qualify or certify the run depending on the tools available to you, that's a given!

Anyway, again a big thank you to Michael for creating this and I look forward to putting this into practice.


2 years ago

Is it possible to embed a microchip programmed with an ID number on
the RJ45 Plug and when making connectivity with the handheld unit report
the ID number on the LCD handheld. I see this is possible with some
bought units but only have up to 20 remote plug ID's. If you have a 48
or 96 port panel you would need ID number for each plug to be as
efficient as possible. If the remotes are analog via voltage I can see
the limit of ID's, but if you are able to put a programmed microchip
that has an ID number report back to the main scanner. I cannot find any
information on this and whether it is possible or not.


2 years ago

Please what is the cost of the project?


2 years ago

Wow I was looking for a project. I think this would do.


3 years ago

Magic!! this is what I was exactly looking for. I am only struggling now to find the 3mm flat LED on Any idea of any other place selling these?

3 replies

Reply 3 years ago

Thanks guys. Project has been completed successfully.


4 years ago on Introduction

Just an FYI for anybody doing this. There are four types of RJ45 connectors. The two shielded options are irrelevant for this project. The unshielded options are based on the type of cable you're using -- solid or stranded. Since the LEDs have solid wires, I would recommend that you opt for RJ45 connectors designed for use with solid cabling.


4 years ago on Introduction

does it make a difference in quality if i order them on ebay of just in my local shop, they are much cheaper online and i need a lot in my house :)

2 replies

4 years ago

I double and triple checked everything. I even did some reverse engineering. It does not work. Any tips from someone who got it working?

3 replies

Reply 4 years ago

When I test the clips neither LED lights up on the clips or power pack.. I'm sure your design is good, probably my poor engineering skills.

If the battery is good and all your connections are solid, then you've probably got something backwards (either the battery or one/both of the LED's).