Wire Limit Switches
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Wire TB6560 to Power Sup
Wire AC Relay
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Wire Limit Switches
Mach3 EStop/Limits TB6560
Mach3 Pins/Ports

 

 

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Wiring the Limit Switches

These instructions will explain how to wire the Limit Switches for X, Y and Z axis's.

Limit Switches are used to let you software know when an axis has come close to or is at the limit of it's physical movement. They work
by being put in such a position that when an axis is near the end of it's travel it will come in contact with it. This will complete a circuit that
is wired back to The TB6560 Driver board which in turn sends a signal to you controller software (Mach3 etc).

There are several different ways to wire these up, with the 2 common methods being Serial and Parallel.
 


The easiest way to explain Serial, is that the signal travels through a circuit in a continuous loop. All the switches
in the circuit are wired as NC. The signal will travel along a wire, in to a switch, out the other side, and on to the
next switch in the circuit. This type of circuit would always be active (on), so any break in the signal (contact at
any switch) will initiate a limit event.

Parallel divides the circuit in to halves with the active signal being on one side and the common on the other. The
switches act as bridges between the two halves and are wired as NO. Contacting a switch will complete the circuit
and a limit event will be triggered.

The Primarily function of all this is to stop your axis's from crashing into their mounts and causing damage to your components.

 

 

Warnings

AC Mains Power can kill or seriously injure you

DO NOT plug in your equipment while you are working on it

Never place your hand in live equipment that contains un-insulated or bare AC terminal and wires.

 

 

Parts Required

Supplied Parts

1 x Mounted TB6560 Driver board

6 x Mounted Limit Switches

1 x Mounted Limit Switch cable (the common cable used for the E-Stop Button is also the common for Limit
     switches)

1 x Previously installed Rail connector(s), these are are installed with the Stepper Motors / Terminal Blocks,
     your wiring will run from there.

12 x 4.8mm Spade terminals

 

Parts to be sourced

Qty? x Meter 2 pair (2 wires run together) wire sufficient to run from the TB6560 Driver board to the Limit
Switches. During the "Wiring Steppes" instructions it was recommended you run 6 core cable, the remaining
2 cores will now be used. If you did not run 6 core cable you will need to source some 2 core cable.

 

Recommended tools

Wire stripper

Wire cutter

Crimping tool

Philips head screwdriver (Small)

 

 

Parts Overview

TB6560 Driver board

  1. Pin 1 - Relay 12/36v DC + in (MIN)
  2. Pin 2 - 12/36v DC -
  3. Pin 3 - Relay 12/36v DC + out (MOUT)
  4. Pin 4 - Z Axis A+ out
  5. Pin 5 - Z Axis A- out
  6. Pin 6 - Z Axis B+ out
  7. Pin 7 - Z Axis B- out
  8. Pin 8 - Y Axis A+ out
  9. Pin 9 - Y Axis A- out
  10. Pin 10 - Y Axis B+ out
  11. Pin 11 - Y Axis B- out
  12. Pin 12 - X Axis A+ out
  13. Pin 13 - X Axis A- out
  14. Pin 14 - X Axis B+ out
  15. Pin 15 - X Axis B- out
  16. Pin 16 - 12/36v DC - in
  17. Pin 17 - 12/36v DC + in
  18. Dipswitch bank 1 - X axis setting
    1. SW1 - Current setting
    2. SW2 - Current setting
    3. SW3 - Decay mode setting
    4. SW4 - Decay mode setting
    5. SW5 - Microstep Setting
    6. SW6 - Microstep Setting
  19. Dipswitch bank 2 - Y axis setting
    1. As per bank 1
  20. Dipswitch bank 3 - Z axis setting
    1. As per bank 1
  21. Emergency stop and limit switch connector
    1. Pin 1 - X Limit (configurable)
    2. Pin 2 - Y Limit (configurable)
    3. Pin 3 - Z Limit (configurable)
    4. Pin 4 - E-Stop (configurable)
    5. Pin 5 - Ground (common ground for all pins)
  22. Display panel connector
  23. D-Sub 15 - Jog pendant Input connector
  24. D-Sub 25 - Parallel cable/PC input connector
  25. Axis activity LEDs
  26. TBA
  27. Cooling fan and Heat sink

 

Limit Switch

  1. Terminal 1 (Signal in)
  2. Terminal 2 (Normally Closed circuit out)
  3. Terminal 3 (Normally Open circuit out)
  4. Roller and Switch lever
  5. Switch actuator
  6. Switch housing
  7. M3 Mounting points

 

 

Wiring/Installation process

Make sure your setup is turned off and the power lead is
not plugged into a wall socket!!

 

Previous task re-cap.

In previous instructions we have used the Rail Connectors to wire the Stepper Motors. These rails where cut in
to 6 terminal blocks, but only 4 of the terminals where used. These instructions will follow on and use the other
2 terminals. You can use a separate block, 2 pin plug, or anything else you might have, or even just wire them
straight through the principals will be pretty much the same.


 

Please note:

Your enclosure is pretty much complete and is packed with wiring. As with all the instructions so far the
components and wiring you are not working with have been omitted as not to be a source of confusion.
If the instructions show wiring going to a used terminal on a Rail Connector in your setup, just use the 
next free on in the same block. Never wire your limit cables in to terminals already occupied by Stepper
Motor wiring. The two are completely incompatible and the current from the driver circuits will damage
the limit and other circuits (24v 3Amp vs 5v 1.4miliamp).

 

Wiring Limit Cable Common to the Rail connectors

As mentioned in the "Wire E-Stop" instruction the Limit Switches also use the common wire connected to the
E-Stop Button. We now need to expand on that wiring to accommodate the switches.

 

Now we need to measure 2 wires to link the other 2 Rail terminals to the first. The first step is to run a length of
wire from where the Limit cable's common wire (DC- Black) enters the first Rail Terminal (labeled "A") to the first
free terminal on another Rail Terminal (labeled "B"). Remember to add an addition 6mm to each end of the wire.
Then run a second wire from "A" again to a free terminal on the the last Rail Terminal (labeled "C", again adding an
additional 6mm to each end.

 

Strip back each end of both wires approx 6mm and give a twist to bind loose strands. Loosen of the terminals at
A, B and C. Insert the wire measure for "B" in to "B" and tighten the terminal. Insert the other end of the wire
from "B" in to "A" leaving the other wire already in place (the wire running from Pin 5 on the TB6560 Driver board)
connected.


Insert the wire measure for "C" in to "C" and tighten the terminal. Insert the other end of the wire from "C" in to
"A" leaving the other wires already in place (the wire running from Pin 5 on the TB6560 Driver board and "B")
connected. If "C" is difficult to insert you may have to remove all wires from "A" and twist them together and
re-insert them. Tighten terminal "A".

 


Wiring Limit Cable signal wires to the Rail connectors

The remaining wires on the limit cable are Pin 1 (Orange), Pin 2 (Yellow), and, Pin 3 (White). Please strip these
back 6mm. These wires are quite small and will require a sharp small gage trimmer. Try not to pull on them to
hard as there is a possibility of breaking the wires inside the insulation.
In these instructions:
Pin 1 (Orange) will connect to X Axis Limits
Pin 2 (Yellow) will connect to Y Axis Limits
Pin 3 (White) will connect to Z Axis Limits

 

The remaining free terminals on The Rail Terminals have been labeled D, E and F. In these instructions:
"E" is attached to the Terminal Rail connected to the "X" Axis cable
"D" is attached to the Terminal Rail connected to the "Y" Axis cable
"F" is attached to the Terminal Rail connected to the "Z" Axis cable
If your setup is wired differently you will have to note which wire (Pin 1, 2 or 3) is being used on the Limit Cable
and run it to the terminal that connects to the corresponding Axis Cable

 

Loosen of the Terminal screws for D, E and F. Insert Limit Cable's Pin 1 wire (Orange) in to to the terminal marked
as "E" on the X axis's Rail Connector. Retighten that terminals screw.

 

Insert Limit Cable's Pin 2 wire (Yellow) in to to the terminal marked as "D" on the Y axis's Rail Connector.
Retighten that terminals screw.

 

Now insert the Limit Cable's Pin 3 wire (White) in to to the terminal marked as "F" on the Z axis's Rail Connector.
Retighten that terminals screw.

 

Check and make sure each Rail Connector has one signal wire and one common wire connected. Your wiring may
not match if you have used different methods for wiring Stepper Motors but as long as you have followed the
right pin to the right point issues won't arise during "Configuring Limit Switches".

 

Wiring Rail connectors to Rail Connectors for Limit Switches

If you have 6 core wire running through your machine there should be 2 wires left over at each end of your cable,
If not you will need to run 3 lots of 2 core or twisted pair (preferred) wire from the Rail connectors in your enclosure
to the Rail connectors on each of your axis's.

From the wires you have left choose which colours you are going to use for Signal and Common. In this example Purple
will be the signal wire and White will be the Common wire. Strip back 6mm off all 12 ends and twist any loose fibers.

 

Loosen off the terminals labeled "A" and "D". Insert the Common (White) wire leading to the Y axis in to the terminal
labeled "A", leaving the wire already there in place. If it is difficult to fit the new wire in you may have to remove
both wires, twist them together and reinsert them. Insert the Signal (Purple) wire leading to Y in to the terminal
labeled "D" and tighten both terminals. The Yellow wire (Pin 2) from the Limit cable should be connected to the
Purple signal wire and the White wire (Common) should be linked to the Common wire (Black) from the Limit Cable.

 

Now loosen off the terminals labeled "E" and "B". Insert the Common (White) wire leading to the X axis in to the
terminal labeled "B". Insert the Signal (Purple) wire leading to X in to the terminal labeled "E" and tighten both
terminals. The Orange wire (Pin 1) from the Limit cable should be connected to the Purple signal wire and the
White wire (Common) should be linked to the Common wire (Black) from the Limit Cable.

 

Loosen the terminals labeled "C" and "F". Now for something tricky, Insert the Common (White) wire leading to the
Z axis in to the terminal labeled "C". Insert the Signal (Purple) wire leading to Z in to the terminal labeled "E" and tighten both
terminals. The White wire (Pin 3) from the Limit cable should be connected to the Purple signal wire and the
White wire (Common leading to the Z axis) should be linked to the Common wire (Black) from the Limit Cable.

 

At the Axis end of the cable there should also be 2 free terminals. Your limit switches may be some distance from
this Rail connector so the images in the following instructions are a guide, please extrapolate as required.

 

Loosen of the spare terminals, insert your wires and tighten. Repeat for other two axis.

 

 

Wiring the Limit Switches so they work as a Serial circuit

Using the same method as all throughout these instructions, measure a length of wire from the Common (White)
terminal on the Rail Connector to Terminal 2 (NC) on the left Limit Switch. Strip both ends of the wire and attach
a 4.8mm spade terminal to one end. Loosen off the Common terminal, insert the stripped wire and retighten.
Connect the end with the spade terminal to Terminal 2 on the left Limit Switch. 

 

Measure a second length of wire from the Signal (Purple) terminal on the Rail Connector to Terminal 2 (NC) on the
right Limit Switch. Strip both ends of the wire and attach a 4.8mm spade terminal to one end. Loosen off the
Signal terminal, insert the stripped wire and retighten. Connect the end with the spade terminal to Terminal 2 on
the right Limit Switch. 

 

The final step is to link the two switches together. Measure a length of wire from Terminal 1 (COM) on the left
switch to Terminal 1 (COM) on the right switch. Strip both ends and add a 4.8mm spade terminal to each end.
Connect one end to Terminal 1 (COM) on the left switch and the other to Terminal 1 (COM) on the right switch.
The limit circuit is now complete.

 

Repeat these instructions for the other two axis

 

 

Congratulations, your kit should now be fully wired, enjoy

 

 

Supplementary Images

No additional images

 

 

 

Next Step

You are now ready to move onto the next step:

TBA

 

 

 

 

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This site was last updated 02/08/14