RJ45 Connections

I am interested in using RJ45 connectors and cat5 cables on my MPCNC, as others have done. I have a crimper for putting the plugs on the cable, but I’ve never worked with the jack side. From what I’m seeing, it looks like the punchdown style would be easiest to work with, but I wanted to hear from folks with some experience using RJ45 jacks have to say.

If you use the punchdown type, does that require a special tool? Also, is it possible to use stranded wire in a punchdown? I’m using breadboard jumper cables cut in half for making the connections to the ramps board, so would like to connect those to the RJ45 jacks.

Any advice is appreciated!

Karl

The punchdown RJ45 modules that I used all came with a simple plastic tool. I think that most or all ethernet wire is stranded. All of mine is stranded and works great. You probably already saw my scheme http://www.thingiverse.com/thing:858155 and https://www.v1engineering.com/forum/topic/placement-of-electronics/#post-4376.
Steve C

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Thanks, Steve. Glad to know I can use the punchdown ones. I did see your forum post and design on thingiverse. I’m really looking forward to having the quick connect/disconnect capability!

I think this is a great idea first off. My only concern is is can cat 5 handle the amp draw?

i have yet to find “ethernet” wire that comes stranded. it comes in twisted and flat but not stranded, unless youre talking cheap cat3 or walmart premade ethernet hookup wire.

this was my concern at first until i remebered that i ran all my speaker wires in cat6. ive been using cat6 to run my mpcnc just fine.

If you’re going to use ethernet cable, use cat6 patch cables. Cat6 wire is larger gauge than cat5. The spools you can get at the hardware stores is made to be used in walls and whatnot, so the wire is solid core wire. Patch cables are made to go from the wall to your device, so they are stranded wires. Stranded wires will take the continuous bending much better than solid wires. Eventually the solid wires with work harden and break, causing intermittant issues. The only issue with this is stranded wires won’t punch down as nice in the network keystones.

Thanks! Thats a very good point about the stranded vs solid core I didnt know about.

Hello everybody,

I have the MPCNC machine finally assembled and found out that I forgot to order the wiring kit with my bundle, which brought me to this tread. When Cat6 cables work fine maybe flat retractable ones (see picture) could be used for bigger machines as well, to keep everything clean and neat. I will order the regular wiring kit for this set up (30x30) and finish the table in the mean time, since it is standing on a cardboard box. But on my next set up (4x6 or 4x8) I would like to use retractable cat6 cables installed in the middle underneath each x and y axis if possible. For the z axis I don’t know yet where the best location would be, but I will figure that out along the way. Can that work, or would the pull (although little) from the retractable cat6 holder be counterproductive?

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Im using RJ45 connectors and my laser works amazingly well.
It wont work for your D660 of course

Anyway, im running 22 gauge from laser to RJ45 jack, then 18 gauge to the board.

That retractable one would look so slick! They do tend to be very small wires in there but if it works it would be awesome. gives me an idea…

Those “Recoil” winders can also be used with other kinds of wires as well and are very cheap too (about 2-3 bucks each). They might need some modifications to work as intended, but whats a 3d printer for? And you could brand them “vicious”. Maybe we can even design our own version when we can find suitable springs.

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Those “Recoil” winders can also be used with other kinds of wires as well and are very cheap too (about 2-3 bucks each). They might need some modifications to work as intended, but what’s a 3d printer for? And you could brand them “vicious”. Maybe we can even design our own version when we can find suitable springs.

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I am a network engineer so the idea of using rj-45 connections appeals to me but I not sure how good an idea it is? You can put ends on stranded cable (like people have send patch cables are like that) with no problems but the jacks are not supposed to be punched down with stranded cable so how do you get around that? I know is works but after a while you will have problems and with all the movement it scared me.

Keep in mind that it’s not the end of the world if one comes loose. Worse case, you’ll pop a driver or a stepper or the ramps. That’s not good, but if there’s a 0.5% chance of it happening every 100 hours, then it’s a risk that might be worth accepting. If you put a ziptie on it next to the connector to relieve strain, I bet it’s even better.

If you have stranded wires, then the dupont connectors are a good choice too.

Michael,

I have been using the punchdown RJ45 modules with stranded wire for a long time (over 2 years) with no issues. http://www.thingiverse.com/thing:858155

As long as the keystones aren’t flopping around they should be okay. Mine are also doubled up, so both color pairs equal a single stepper color. Cuts the odds down. One cat6 wire can easily handle the stepper current.

The stranded wire is constrained by the insulation, so when pressed into the punch down block the insulation parts giving good contact to the stranded wire. If you stripped the wire first it wouldn’t work as well since the individual wires would fan out.

I lean toward using the easily found solid core wire in places that have minimal movement, such as the through wire inside the X or Y center tubes and patch cables within my chain. No where is there enough current going through these wires to be an issue, if there were you would just put something like a relay in to separate the control wiring from power.

I agree that stranded wires are a better choice for RJ45 connectors on a MPCNC due to their flexibility. Solid core wires are more likely to break with repeated bending.