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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
ways to wire these up, with the 2 common methods being Serial
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.
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.
Primarily function of all this
is to stop your axis's from crashing into
their mounts and causing damage to your components.
AC Mains Power
can kill or seriously injure you
DO NOT plug in
your equipment while you are working on it
your hand in live equipment that contains un-insulated or
bare AC terminal and wires.
1 x Mounted
TB6560 Driver board
6 x Mounted Limit
1 x Mounted Limit
Switch cable (the common cable used for the E-Stop Button is
also the common for Limit
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
Parts to be
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.
- Pin 1 - Relay 12/36v DC + in (MIN)
- Pin 2 - 12/36v DC -
- Pin 3 - Relay 12/36v DC + out (MOUT)
- Pin 4 - Z Axis A+ out
- Pin 5 - Z Axis A- out
- Pin 6 - Z Axis B+ out
- Pin 7 - Z Axis B- out
- Pin 8 - Y Axis A+ out
- Pin 9 - Y Axis A- out
- Pin 10 - Y Axis B+ out
- Pin 11 - Y Axis B- out
- Pin 12 - X Axis A+ out
- Pin 13 - X Axis A- out
- Pin 14 - X Axis B+ out
- Pin 15 - X Axis B- out
- Pin 16 - 12/36v DC - in
- Pin 17 - 12/36v DC + in
- Dipswitch bank 1 - X axis setting
- SW1 - Current setting
- SW2 - Current setting
- SW3 - Decay mode setting
- SW4 - Decay mode setting
- SW5 - Microstep Setting
- SW6 - Microstep Setting
- Dipswitch bank 2 - Y axis setting
- As per bank 1
- Dipswitch bank 3 - Z axis setting
- As per bank 1
- Emergency stop and limit switch connector
- Pin 1 - X Limit (configurable)
- Pin 2 - Y Limit (configurable)
- Pin 3 - Z Limit (configurable)
- Pin 4 - E-Stop (configurable)
- Pin 5 - Ground (common ground for all pins)
- Display panel connector
- D-Sub 15 - Jog pendant Input connector
- D-Sub 25 - Parallel cable/PC input connector
- Axis activity LEDs
- Cooling fan and Heat sink
- Terminal 1 (Signal in)
- Terminal 2 (Normally Closed circuit out)
- Terminal 3 (Normally Open circuit out)
- Roller and Switch lever
- Switch actuator
- Switch housing
- M3 Mounting points
Make sure your
setup is turned off and the power lead is
not plugged into a wall socket!!
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
through the principals will be pretty much the same.
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).
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)
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".
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
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
"E" is attached to the Terminal Rail connected to the "X" Axis
"D" is attached to the Terminal Rail connected to the "Y" Axis
"F" is attached to the Terminal Rail connected to the "Z" Axis
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
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
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".
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.
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
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
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.
instructions for the other two axis
Congratulations, your kit should now be fully wired, enjoy
You are now
ready to move onto the next step: