Limit switches and connectors

I’m upgrading an older machine to the superlongboard and the connectors for the limit switches and axis control are different.

  1. What is the type of connector for the z, y2 etc?

2.) how do I wire it if y2 isn’t available yet? My setup is 4 wire right now and I’m not familiar with the original longboard

3.) how do I wire the limit switches if there’s only one slot for each switch? Mine are currently physical switches with 2 wires.

4.) would it be a good idea to get rid of my physical limit switches and get something more reliable? I’m not sure if a Hall effect is a good choice or anything else someone could recommend. I worry it will blow past it if I’m doing this super speed homing the SLB is known for.


Also, if anyone had an idea of how to hook up the

Hey @cncdm,

You can check out our resource page on the Longboard details, it includes the current SLB connectors for both the X,Y,Z axis and the limit switches HERE.

You can simply wire up Y1 and not use Y2 at this time, you only need one to signal you are homed on the Y axis. Dual axis homing is coming, but not ready at this time.

Hope this helps,

Does this just apply to the limit switches? I assume I need both motors connected. But I still don’t understand how to connect them when they have two wires and the slb has 1 slot per

Yes, you will need to have all 4 motors wired up. You can skip the Y2 connection, but only for the homing switch. If you share some pics or more info on your setup, someone may be able to help out with your wiring setup.


Here’s a shot of my old rs485 connector. I don’t know how to make a cable that connects my VFD to the SLB using an Ethernet connector.

The next shot is my two wire limit switch. I don’t know if I only use two wires on JST or if I need new cables. If I use the auxiliary terminal, which wires get connected since there’s only one slot for each axis?

Uploading: image.jpg…

I’ve been over the manual for it and my answer isn’t in there. I’ve got nc/no limit switches wired with two wires to my older grblhal controller but I don’t understand if I’m to use the JST connections and if so, which pins, or if I can use the the larger limit switch plug with VCC, X, Y1, Y2, Z, A, GND. If it’s the latter, which wires go where?

Also I have no idea how to connect the RS485 wires from my VFD to an Ethernet jack that would be plugged into the SBL. My Huanyang VFD uses approximately 18 gauge wire for its rs485 connection and I’m not sure how that fits into an Ethernet jack for making a cable. Can you purchase the cable?

Have you found an answer? I’ve been trying to understand how to connect rs485 and nc/no limit switches for a few weeks and haven’t heard anything from support. Starting to wonder if I’m going to miss my return window if it isn’t possible but the slb page says it should be compatible with most machines.

I don’t care what it takes, I just need to know what to do. My next option is get a Blackbox but the downtime I’ve already had is killing me

@cncdm You should open a support ticket if you haven’t already.

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I have not heard more. As for the rs485, I can only say to be patient. And, as was suggested, to open a support ticket.

@cncdm What machine are you running? Be sure to include that in your support request. I assume that the section on RS485 in the SLB manual didn’t give you the info that you need.

Support ticket has been open since late April. The follow up time is roughly a whole week though. And I thought I had it bad with Bulkman 3d.

No there’s no mention of how you splice the rs485 cable into an rj45 connector.

The function of the limit switch pins seems simple enough too, but not a word.

I’ve talked to support twice but they don’t directly answer my question. Last reply I sent was may 3rd

I’m running an ultimate bee with a huanyang VFD and 2.2kw water cooled spindle. It’s got micro limit switches which I’m willing to upgrade for better compatibility.

@cncdm via the manual there are two ways to get the RS485 output, either via the jack or the provided connector on the board that requires no crimping just a flathead screwdriver:


For the limit switches are they NC or NO? I wouldn’t advice mixing and matching them, rather you’ll need to choose one or the other. If you’re hooking them up on both ends, I’d advise you use the larger limit plug. The wiring configuration will be similar to what we have written for our older board:

Regarding response times, I looked at your ticket and am also confused on the response times - so I’ll look further into that.



Switch is just labeled 1 2 and 3. 1 to red and black to 2. I honestly forget what position that is but I’ll look soon

Is there a manual beyond the setup? I didn’t see the part about using a screwdriver connection

These are the three jacks I received

I don’t have the the a- and 5v wires connected to my hy huanyang.

Yes there’s the Setup or ‘Switch over’ procedure page for guidance on typical setups, then there’s a much more in-depth ‘Manual’ page that goes over everything in much more detail for people doing more custom setups or in-depth customization, it’s the page I linked in my last comment

Your sensors look like they’re set up for NC, but yes I’d recommend double-checking that

The picture you have are of the spare jacks to connect to the ends of the board, but if you open up the cover you’ll find that there’s a row of green connectors along the top that can all come out and have wires hooked up to them, that’s where you’ll be able to attach the RS- and RS+ coming from your VFD

Did you see the pic I edited in? I only used the + - rs wires. I’m not sure if I need the other two that are shown in the manual

Yes I saw it. No you probably don’t, they’re optional depending on the persons setup

Great thank you. I’ll try it this afternoon. Is there any reliability difference in the two ways to connect it?

I’m willing to do some more work to this thing so I can have it run as smoothly as possible

The reason people typically opt for NC is that it’s safer, if the wires get severed at any point then it immediately signals the CNC that a wire is triggered when it shouldn’t be, so you can make sure to fix it. For some people though they don’t care as much if their limit switches fail when they go to home so they’ll choose NO, that way if a wire comes loose during a job it won’t abort the cutting for something they don’t find to be very consequential. Essentially it’s preference, it seems though like you’d opt for NC

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Your skills in assessment are impressive :laughing:.

Thanks again. I’ll give that a shot and see how it goes. I’ve never used g sender but I’ve programmed cncjs and fluidnc. Looks like plenty of info available but if anything sticks out about my situation please let me know