Sure, the USB interface has a place for 4 axes of limit switches.

Each axis can have two limit switches: one for the ++ (positive) end and one for the -- (negative) end. The positive end would be the limit switch at the end of the machine that, say the machine has a 4'x8' area, reaches a bit after the 8 foot mark. The negative end would be the limit switch behind the 0 foot location behind the origin. If the origin is in the middle, the negative would be at a little more than the -4 foot end and the positive would be at a bit more than the +4 foot end. Note that you can have more than one switch on each pin where the NC is connected in serial fashion and the NO is connected in parallel fashion (this can be seen on the diagram in the multiple limits switch section). The software configurations for the limits switches are under File -> Settings -> Limit.

A typical limit switch has three connections on it. These connections consist of COM (common), NC (normally closed) and NO (normally open). The COM would generally go to GND and the NC or the NO would go to the pin. If the NC is used, then the the switch is constantly connected until the switch is pushed (engaged) then the connection from the pin to gnd is broken (open). Use the settings in software to set whether in NC or NO configuration.

Let me know if this information was helpful (or not) by adding information to this question. Thanks.

User response:
Thank you very much for this helpful information. I'm still a little fuzzy on how the 6 limit switches physically connect to each other and to the USB breakout board. You've stated one switch (home) goes to positive and another switch (limit) goes to negative. Are all the GND prongs from all 6 switches connected to each other and going to GND on the breakout board, or no? And the NC prongs, how exactly are they connected to each other? And to the board? There has to be a diagram somewhere shows this visually, no? I don't know how to wire the switches in series or in parallel. I have already physically installed all the switches on the machine and ran the wires to where the board is. Now I just need to know where to plug these wires into the board. Also, taking into consideration that I'm using the Planet CNC software, the only settings I have pertaining to limit switches is "Enable/Disable" for each axis, and the actual limit for each axis. Nothing about NC or NO. Is that only in Mach3?
Thank you.

buildyourcnc response:
On the USB interface, the COM on the switch connects to GND and the NC or NO connects to the input pin (i.e. x++, y--, etc.)

Limit switch configuration is rather difficult to understand, especially with series and parallel. You can think of series as a single wire going from GND to the axis letter input terminal (i.e. X++ or X--). If the wire is broken, then the circuit is open (or the switch is engaged in a normally closed scenario). Normally closed is like an actual wire, and when engaged, the switch "opens" (breaks the wire). This is why we recommend in some systems that you can put many switches in series on a single pin. When one of the switches is engaged (breaking the connection) then the entire circuit of switches is broken and the machine stops.

In a parallel scenario, the state of the circuit is always broken until the one of the switches is engaged and the circuit is then closed or connected. The topology looks like a ladder. All the switches connect to both sides of the ladder and the switches are like the runs of the ladder (the horizontal bars that the feet are placed while climbing). Imagine all of the switches broken in this scenario (normally open). It would be like the ladder could be split in two, but if one of the ladder runs (switches) is closed by engaging it, then that run would connect both sides of the ladder and the two sides of the ladder would have a connection.

There is a diagram on the USB page of the various limit switch configurations. If you need more information (visual and/or otherwise), please let us know and we will immediately add that information to benefit everyone.

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I have nearly completed the CNC machine from the book, but I am using it with a USB breakout board, and have no idea how to wire the 6 limit switches to the board. I'm having difficulty following the diagram on the USB breakout board screen. Can someone please help me?

I would not recommend slaving an axis using the method of taking an additional axis from the USB interface. Instead, wire both drivers to a single axis on the USB interface. This will insure perfect signal output to both drivers. If you requre the motors to spin in opposite directions, simply wire one of the motors to the driver reversing the coil A and B connections, or use a hex inverter (https://www.buildyourcnc.com/tutorials/Tutorial-Two-Motors-Spinning-Oppositely-On-Single-Axis).

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I purchased a USB Breakout board, motors and drivers, paid for CNC USB Controller Software and I CAN NOT "Slave" an axis, but there is an option to do that. The moment I connect USB Breakout Board "Slave" option becomes shaded and I can no longer select it (becomes not functional). What is going on? Need help asap. Thanks

To connect the parallel port breakout board to the LEDs, use step number 18. The connections are listed at the bottom. Here it is for your convenience.

For the LED connections on the parallel breakout board:

- The x axis LED will be connected to pin #2 and 5V
- The y axis LED will be connected to pin #4 and 5V
- The laser on/off LED is connected to pin #6 and 5V

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I can't find any information in the BlackTooth instructions about how to connect the 8 wires from the LED display to the parallel breakout board. The two going to the pot seem, in the illustration, to be soldered together and to the centre terminal of the pot? Help, please.

The datasheet for the parallel breakout board is here:
https://www.buildyourcnc.com/item/electronicsAndMotors-parallel-breakout-relay#prettyPhoto/2/

The datasheet for the USB interface is here:
https://www.buildyourcnc.com/item/electronicsAndMotors-electronic-component-USB-Controller-Breakout#prettyPhoto/2/


Additional Information:
20

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I need wiring instructions for the breakout board you sent yesterday. It is not like the one in the videos and I don't know where to connect the 5V. No data sheet or anything.

To setup mach3 for the parallel breakout board, view the last three videos on this page:
https://buildyourcnc.com/CNCElectronicsandWiring.aspx#prettyPhoto

The parallel breakout board contains a usb connector, but is only used for power. The USB interface board (sold here: https://buildyourcnc.com/item/electronicsAndMotors-electronic-component-USB-Controller-Breakout) does not use Mach3, rather it uses the planet-cnc software.

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bluechic v4.2 - mach3 setup video does not play on the metacafe site... since I'm new to this I am lost on how to configure mach3 to the usb breakout board. Please advise, thanks!

You can see the component list on the hardware and plans machine (scratch build machine) since it is the same machine in the book:

https://www.buildyourcnc.com/Item/cnc-machine-scratchbuild

Additional Information:


Additional Information:
Your book claims that plans are available for download, not purchase; the "plans" included in book are illegible and sometimes dimensions omitted - e.g. Fig 3.6 is cutout plan but dimensions are missing from dimension arrows. Your call to provide or not provide plans on the website but should not claim to if you will not. I'll hold my putting review on Amazon until I hear back from you. All I'm asking for is legible dimensions - PDF format will work but I'll ANY legible format. Thanks for your consideration.

Additional Information:
A PDF version of the plans are available here: https://www.buildyourcnc.com/Book.aspx

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I bought Kindle version of DIY CNC book; pictures are illegible. I can't find a place to download actual PDF plans on site. Can you please provide a link? Thanks

To connect the stepper motor drivers to the Mach3 USB interface card, you will need to follow the wiring diagram here: https://www.buildyourcnc.com/Documents/Electric%20Wiring%20Diagram.pdf
which can be found here: https://www.buildyourcnc.com/item/electronicsAndMotors-electronic-component-breakout-Mach3-USB-Board along with all of the other manuals associated with that interface card.

Please note that the DC+ and DC- on that wiring diagram (power supply to thye stepper motor drivers) is not correct. The DC- is connected to GND on the drivers and the DC+ is connected to VCC on the drivers. Typically, the DC+ on the power supply is labeled V+ and the DC- is labeled either COM or V-.

If you are having any issues with the wiring, please let me know and I will elaborate. Thanks.

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Yawl sold me a ST-USB MOTION CARD I have surched all your electronics and can't find wring instructions I need to know where to connect X,Y and Z to this controler

The e-stop should be wired like a limit switch and can also be within the same limit switch circuit. Use one of the input pins to create the e-stop circuit.

1. Run a wire from the input pin terminal to the e-stop switch red side (one of the two terminals on the red side). The red side is NC (Normally Closed).

2. Run a wire from the other side of the red side of the e-stop switch back to the gnd terminal (or to the next switch - limit switch, NC terminal, then back to gnd, or to the next NC terminal of the next switch, do you see a recursive pattern here?).

The wire that you use for the connections should be shielded and the shielding and any other loose wire within the cable should be tied to gnd.

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Hi - I have wired in a breakout board (with relay) as per suggested wiring instructions (black toe 2X4). I want to wire in an estop but need some guidance on wiring. Also Mach3 is requesting I reset the estop, which suggests its expecting one? Can anyone help? Thanks. Miles

Connecting the limit switches on the redLeaf use the input pins on the parallel breakout board. Here is a link to the wiring diagram for that parallel breakout board.

https://buildyourcnc.com/item/electronicsAndMotors-parallel-breakout-relay#prettyPhoto/2/

The connection is simple. Just create a circuit from ground to the pin. When the pin is engaged, the circuit is closed (using normally open on the switch). Use mach3's autoset to automatically set the pin for the limit or home setting.

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Do you guys have any videos showing how to connect limit switches to a redleaf? If not, could you please make one? I looked at the diagrams on the limit switch page but I don't understand them.

For safety's sake I would recommend a new board because they are inexpensive compared to the electronics that they support. Alternatively, it's possible that the one dead pin is a simple fix, such as a bad connection or solder joint; if you feel comfortable making those repairs then it could be worthwhile to check. Finally, if you are not using all the input pins, you could continue to operate the limit switch on pin 11 and hope for the best.

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I have a breakout board and it appears that the pin 12 connection has failed: when i move my limit switches to pin 11 they work; they don't work on pin 12. Do i need a new breakout board?

This video should provide enough guidance to understand the PWM signal on the Mach3 USB controller:

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[575] Hello, I'm wondering if you can provide advice how to wire this USB board where for spindle I would like to use chinese servo motor and driver (TD3) - speed control mode. Especially how to connect - AVI, ACM and 10V (24V is clear). I am still not sure how to power on and off spindle itself. Thank you in advance. Vaclav

NC mechanical switch configuration is supported. You can download the manual from this page (Mach4 plugin and manuals):
https://buildyourcnc.com/item/electronicsAndMotors-electronic-component-breakout-Mach4-mach3-USB-ethernet-Board

The pokeys57CNC controller has input terminals and pins for limit switches on each of the 8 axes. There are three separate inputs per axis, two for the actual limits of that axis, and one for the home position.

Connect each switch between the GND terminal and its respective axis limit terminal/pin. For instance, the limit switch will typically have three leads, COM, NC, and NO. In an NC configuration, the NC connects to the terminal/pin, say, Axis 1 lim +, and the COM connects to the GND terminal.

In Mach4, in the new device wizard, make sure to specify the correct option on the home and limit switches that matches the machine configuration.



Additional Information:
can you use one switch per axis for home only?

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Hello, I am trying to configure Home and Limit switches using the Pokeyes57cnc and NC switches. I am confused on the procedure of setting this up. wiring to the board and setting up in Mach4. Can you direct me to a tutorial or offer some suggestions? Thanks Dale

Have you tried a different input pin?

Customer response:
I've tried all pins: 10, 11, 12, and 13. I get the same non-response in each case.

Recommended action
There may be a problem with the board. If you are using our parallel breakout board, we can ship you a replacement (call us), otherwise, you will need to determine the problem with the vendor of the breakout board you are using.

Additional Information:
I have tried 3 different breakout boards from 3 different providers and they all do the same thing My limit switches are microswitches wired NC with each axis wired to the BO Board. I have checked each circuit and all is OK to the BO board. each circuit has continuity at the board and when any switch is pressed the circuit breaks. Mach 3 does not recognise that the switches are even there. They are configured as active low Do you have a suggestion.

Additional Information:

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I'm having trouble getting Mach3 to recognize my limit switches. I've eliminated everything back to the breakout board. I can directly connect Input 10 to GND on the breakout board while Mach3 is in autorecognize mode and Mach3 doesn't acknowledge anything.

From the USB controller, the CP+ and CW+ are connected to the 5V terminal. The CP- is connected to the CP terminal of the driver and the CW- is connected to the CW terminal of the driver.

Additional Information:

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Please explain how to connect 2.5AMP stepper motor driver to USB board. All parts are from your store. Thanks

BYCNC Response:
This is correct. You will need to use a method appropriate for the software you are using. Also remember that NC switches are typically wired in series, while NO switches are normally wired in parallel.

User Response:
I am using the cnc planet software for your USB board. Are the limit configurations in this software?

BYCNC Response:
Yes, Planet CNC software is compatible with the use of limit switches. Configuration information will depend on your specific application. You can view Planet CNC's information here: http://www.planet-cnc.com/files/CNCUSBController.pdf

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LIMIT SWITCHES FOR AXIS. THE PRINT SHOWS THAT YOU CAN WIRE LIMITS EITHER N.O. OR N.C. SO IF THIS IS CORRECT I WOULD NEED TO TELL BOARD IN SOFTWARE HOW LOOK AT THESE LIMITS, I'M GOING GET AN INPUT LOOSE DEPEND ON IT.

Yes, the Mach3 USB board has two terminals that require 24V connection. Most VFDs have a 24V output that can be used to power this part of the Mach3 USB board.

The V+ and V- on the Mach3 USB is not absolutely necessary to operate the CNC machine/router. The V+ and V- of the Mach3 USB board powers the outputs, inputs, and spindle's speed and control.

Here is the Mach3 USB link for more information:
https://www.buildyourcnc.com/item/electronicsAndMotors-electronic-component-breakout-Mach3-USB-Board

The new YL600 VFD we have in stock may not have this 24V output. There is a 12V terminal, but I have not tested that terminal if it outputs 12V, or if it is a 12V input. If you are only conecting limit switches to the Mach3 USB and need to power that portion, 12V will be sufficient.

I will delve into these aspects in far more detail on video.

Thanks and Merry Christmas to you as well!

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Hey Guys, I have a brand new redleaf and 5x. In the final stages of wiring and wondering a few things. Can I connect the Mach3 USB board V+ V- to my frequency inverter (type YL600-2s-2k20)? If so where? Will your upcoming (part 2)video deal with this as well as final connections for limit switches and stop button? Merry Christmas!

can not get the limit switches to work on the usb controller board

Additional Information:
Wiring the motors to the drivers for our 8 wire motor is probably the 425 oz-in NEMA 24 stepping motor. Here is the URL for the diagram of the motor:
https://www.buildyourcnc.com/Documents/PN.SM60HT86-2008BF-U%20(inhouse%20PN.60BYGH303-13)%20(1).pdf

Wire it in bipolar parallel as specified on the data sheet.

Here is the URL for the motor to check if it is the same that you purchased.
https://www.buildyourcnc.com/item/electronicsAndMotors-nema24-425ozin

The USB mach3 board URL is here:
https://www.buildyourcnc.com/item/electronicsAndMotors-electronic-component-breakout-Mach3-USB-Board

The wiring diagram is on that page and instruction on how to use it.

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I recently purchased the 3 axis mach3 usb kit the motors have 8 different colored wires (no stripes on wire just solid color) all instructions have different colors. cannot find tutorals. does the mach 3 hook up same as planet? please let me know where I can find wiring diagram to hook up mach 3 usb BOB and motors (I am new to this kind of work projects)

Yes, the best way to attach a relay to the output of the Mach3 USB board is to use an SSR (Solid State Relay) at the 24 Volt rating. This is the standard supply for this side of the Mach3 USB board.

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I am converting from a Parallel Port to the Mach3 USB. My limit switches can accomodate up to 5VDC and I want to Drive a Relay from one of the outputs. Will my switches work and do I need a 24VDC Relay?

No, you should not have received two parallel breakout boards in your CNC kit. You can return the extra item using standard shipping with COD. Our apologies for the confusion and the inconvenience.

I will answer the other question as another FAQ. Please check the Customer Service page to see the answer to that question.

If you have difficulty finding the answer, here is a link:
https://www.buildyourcnc.com/FAQ/13636

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I HAVE A 2000 WK 11–3 Z LIMIT SWITCHES GOING TO C10R10 BREAKOUT BOARD . CAN ALSO USE THEM AS MY HOME POSITION WELL. NEED THE WIRING CONFIGURATION