# E Stop Button Question



## speedre9 (May 31, 2016)

One more question. I have a wiring diagram from an Australian site that show the e-stop with one wire connected to the controller board along with the limit switch wiring. Is that corrects, if not show me how. The board I have does not have DB connects on the board instead, it has screw terminals. What has me vexed is, is it one wire to the e stop pin or must I also connect a ground?.
Most diagrams I've seen don't show either way, HELP.


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## British Steel (May 31, 2016)

Whatever it connects to, the E-stop needs two wires... otherwise there isn't a circuit for it to break?
E-stops are normally-closed so operating them opens the circuit - this means that you can add further E-stops by wiring in series.

Dave H. (the other one)


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## jumps4 (Jun 1, 2016)

the one wire you see is the pin number assigned to the e-stop there is probably a ground terminal near the limit and e-stop pins on the breakout board. the other side of the normally closed circuit connects to it or pin 25 on the breakout board to complete the circuit.  
pics would help here of the breakout board or the model and manufacturer.
Steve
 Example:


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## speedre9 (Jun 1, 2016)

Thank you it clears the issue up for me. I don't need to use a BOB with the TB6560. This model board, it seems, comes in three different version, one that is a three axis with a fourth axis capability, one with all DB style connections points, and the one I have with a serial DB25 connector and all screw terminal blocks. All of them have or don't have heat sinks and or fans mounted onboard. Thank you all.


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## speedre9 (Jun 6, 2016)

I should correct the post the board I have is a TB6600 4 axis controller. What I really need is a simple wiring diagram for limit switches, each axis, and an e stop.
Can anyone help me with that. I seem to get a brain freeze when looking at schematics. Thanks


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## chevydyl (Jun 8, 2016)

It depends on what your limits are to do, you can wire them in series requiring one input, or with each limit having an input, do your switches need to be home switches as well? Or is there going to be a third switch on each axis for home, I would wire them with each switch having an input, and in the control make one of each axis the home, requiring six inputs for a 3 axis machine. The common wire will go from the board to one side of each switch, Daisy chained, the output of one each axis of the switch can go to a single in out on the board or 3, the other other 3 switches will go to an individual input for home function

It helps to know what controller your using mach3 or what


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## speedre9 (Jun 22, 2016)

I use Mach 3 with the board pictured. What you asked is my dilemma. Do I need home switches or can I use just limits alone? I have a schematic for one with home and limits but don't really understand the uses for both.
Do they operate as such; when the limit  switch is engaged will it stop the machine and back off a little, and why is one designated as home?


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## jbolt (Jun 22, 2016)

In your example above with both home and limit switches, the limit switches are wired in series to pin 15 so if any of the switches are triggered the machine will e-stop. The home switches are wired in parallel with each switch having it's own input on the board, 10,11 & 12. In Mach3 you setup each input as a home or limit. So in this case 10,11 & 12 are configured as home switches but also act as limit switches. In mach3 when you select a Home command for one or all axis Mach3 will move the axis in the direction of the home switch (assuming you have setup the direction correctly in mach3) until it triggers the switch, stop and then back off the switch until it closes. The axis is now "Homed" but no E-stop has occurred. If during a program run the axis triggers the home switch it simply acts as a limit switch and E-stops.

Homing a machine can be useful if you are using multiple fixtures where each fixture can have a different "Zero" or "Offset" G53, G54, G55 etc. 

In the machine setup you can define the total travel of each axis so when the machine is homed Mach3 will know the available work space. Also "soft" limits can be set where the axis will stop or slow as it nears the soft limit but before the hard limit (switch). This can be useful where Mach3 can warn you if the g-code program will exceed the machine limits. 

Another use for homing is that mach3 graphically displays the position of the part in the work space which can let you know if there is potentially something is wrong with the g-code

If you are not concerned with homing then all the switches can be wired in series with one input to pin 15. 

You can use a switch one each end of the axis travel or a single switch on the moving part of the axis with a trigger block at each end or a combination of both.


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## speedre9 (Jun 23, 2016)

Although I still don't fully grasp this concept, yet I feel by you explanation that if I used this wiring schematic I should feel confident I have a safe machine.


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## jbolt (Jun 23, 2016)

speedre9 said:


> Although I still don't fully grasp this concept, yet I feel by you explanation that if I used this wiring schematic I should feel confident I have a safe machine.



It can take a bit to wrap your head around it. Once you go through the setup it will make more sense. 

What is the machine? Mill, router, lathe or ????


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## speedre9 (Jun 26, 2016)

Gantry Router so six switches needed.


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