Generation 3 Electronics/Tech Zone Remix/Installation

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This page has been flagged as containing duplicate material that Generation_3_Electronics/Tech_Zone_Remix/How to also attempts to cover.
These pages should be merged such that both pages do not attempt to cover the duplicate topics.

Overview

This page will attempt to provide information on how to connect all the electroncis together, and make sure they are performing as they should.



General information


Making the Cables (I know, they are a pain...)

The majority of the problems that users first run into, as they assemble and connect the electronics, are related to the assembly of the cables themselves. It is important to make sure your cables are properly assembled, and test them to make sure that they have good continuity.


Ten Pin Cables With Black IDC Connectors

The assembled ten pin cable
Positioning the cable over the connectors.
pressing the cap onto the connector
A photo of a finished end

The ten pin cables are fairly straight forward. You simply lay the cable on top of the contacts (top right photo) and then place the "cap" over them. I use a board to press the cap on evenly (like in the second photo on the right), since uneven pressure may result in a broken cap and incomplete electrical connection in the cable.

What you need to watch out for on these cables is to put the red edge the same direction for BOTH ends of the cable (look closely at the top left photo for details), if you get one end backwards from the other, then the cable will not work as it should.


Two, Three, and six pin cables

The assembled three pin cable
Spread the wires to fit the connector.
Positioning the wires behind the contacts.
pressing the wire into the contacts
Testing the cable
These cables may have white, blue or green connectors, they work the same way regardless of the color. all three sizes of connectors are assembled in the same manner. Some people prefer to scavenge connectors off of old computers or other electronics, rather than assembling these cables... this is also fine.

The cables need to be split and separated near the ends, so that they will fit the spacing of these connectors.

You then tuck the end of the cable into the space just past the IDC contacts in the connector. You can then press the cable down into the IDC contacts using a small screw driver or other thin, rigid tool.

I have had my best success using a small piece of sheet metal, with the edges curled over so that I don't cut myself while pressing the cables in. If you don't have a small enough flat blade screw driver (one that is too large will spread the contacts and they will never sever the insulation to make contact with the wire inside), you can cut a notch into your screw driver, so that it can press down on the cable on each side of the contacts.

When your cables are done being assembled, you can test them with a multimeter, just touch the probes to the metal that is revealed on the side of the connectors.

The pictures show a three pin cable being assembled, but all the cables are assembled in the same manner.


Hooking up the Main board

Shows all the wires connected stepper controller
A close up of the power wires.

These two pictures show the mainboard all wired up. the picture on the left does not have the two, two pin wires connected, so that they don't get in the way of the others.

The USB to TTL adapter connects to the mainboard with a six pin cable. The six pin cable connects on the left of the board, and the "keyed" pin is to the top (opposite of what the extruder board 6 pin key is set to). The board gets its power from the USB port, so that the board is powered on when this cable is connected.

The X, Y, and Z axis connect to the top of the mainboard with ten pin connectors. Each cable runs to its respective stepper controller.

The two pin connectors both go to the extruder controller, the one on the top is the SDA/SCL pins and carries the step and direction information for the extruder's stepper motor. the lower cable is RS485 and can conect to any of the four sets of pins on the mainboard. The keying on this connector is down in the photo. You can connect up to 4 extruders to this mainboard.


Hooking up a Stepper Controller

Shows all the wires connected stepper controller
A close up of the power wires.
A close up of the motor wires
Another close up of the motor wires, with a different set of wire colors.
shows the direction of the cable connection to the opto endstop.

On the top left, is a photo of the stepper controller, with all the wires hooke up to it.

The ten pin connector connects to the correct location on the mainboard (X, Y, or Z) as you make that cable, make sure that both ends have the color coded portion the same direction, if you put your cable together with the red stripe at the opposite end of the connector from what I have, then your cable will appear to be reversed from mine. This is OK as long as both ends are done the same.

The three pin connector is connected to the opto endstop, in this photo, it is connected to the min the other three pins are for a max endstop if you want to hook one up the red end of this cable is connected to the 5v+ on the actual endstop, that pin should be mated to the pin furthest from the led, the led is the little white thing on the bottom left of the opto endstop in the photo (as in the third picture on the right)

The top photo on the right shows the power connection. The yellow wire in this photo is the 12v+ and the black wire is the 12v- the terminal blocks should be labled.

The second photo down on both the left and right shows the connection of the motor wires. The left photo shows the blue, red, green, and black and the right photo shows another colored set. If your motor is going the opposite direction from what you expect, then swap them by 180 degrees, for example switch blue and black with each other and switch red and green with each other.

More information about stepper motor wiring can be found at Stepper_wiring This may also help you connect different types of stepper motors.


Connecting the Extruder Controller

There are several wires that hook into the extruder controller. The photos and descriptions below have most of the wires not featured in the photo removed, for clarity. You will need to hook all the wires up, before it will work completely.



Connecting Power, Motors, and Other Loads to the Extruder Controller

The screw terminal blocks, should be labeled, and fairly self explanatory, but I know that Photos are far more effective than words (or in this case labels).

Shows all the wires connected to screw terminals
Shows the power wires and the wires connected to the heater on the extruder tip.
Shows the motor wires
Another set of motor wires.
The top picture on the left is a photo of all the wires going into the screw terminals (all other wires have been removed for clarity). On the right, the power wires are connected, as are the two wires leads for the heater on the extruder tip. The power wires are polarized and the 12v + should be connected to the second position (yellow in this photo) and the 12v- (or ground) should be connected to the first position (black in this photo).

The heater leads are red and orange in this photo, but it does not matter the color, or order of these wires. They are connected to the C position on the terminal blocks.

A and B positions on these terminal blocks can be programmed for other loads, such as a cooling fan, or a heated bed.

The second photo on the left is of the motor wires. I have used the most common color of wires, but your may be different. If the motor direction is reversed from what you expect, then simply flip all the wires 180 degrees, by swapping blue with black, and red with green.

The second photo on the right is just like the photo on the left, but with a different colored set of wires

More information about stepper motor wiring can be found at Stepper_wiring


Connecting the Main board to the Extruder Controller

Both of the wires that connect the Main board to the Extruder Board
Close-up of the wires on the Extruder end.
The main board is connected to the Extruder board with two separate wires. The first wire (shown as the bottom wire in the photo) is the RS485 communications wire, the main board communicates over this wire to the extruder, to give it commands, and to receive information back (like the temperature of the Hot End). The second wire is only needed if you are using a stepper motor with your extruder. It uses the I2C communications port off of the main board and the D9/D10 pins on the extruder Controller. This cable carries the step and direction information for the extruder's stepper motor.

A little background: These two boards are connected together with 2 wires, in most of the modern implementations of the RepRap, but the original design only used the RS485, and expected you to use a variable speed DC motor. When the extruder evolved to use stepper motors, someone figured out how to make all of that work (with timings, PWM and other technical stuff I am not going into on this page), but it requires the second connection to pass the working information to the extruder, this is required, because the RS485 communications protocols are not "Fast" enough to deal with the information needed for the stepper motor

The photo on the right is just a close up of the same wires.


Guy Pommares didn't like the default electronics mounting board, so he made a different one. (I kinda like it!)
The photo to the Left is a picture of a Machine owned by Guy Pommares. He felt like the front electronics mounting board was in the way, so he made a different one and mounted the electronics on the side. (This picture is posted here with his permission, Thanks Guy!)

Also of interest in this photo, he made a belt tensioner for the X axis, you can see it near the bottom right of the photo.


A few different ways to connect Temperature sensors

There are several ways to detect the temperature of the hot end of the extruder, below we have shown a couple of them. Use the one that fits your configuration


Connecting in the TechZone Thermocouple A/D converter

This converter is in a pre-release format, and is a variation of the adapter found on the Thermocouple_Sensor_1_0 page, but we have changed the firmware so that you do not need to remove the capacitor as shown in the instructions under that link. (Read that page for background, history, inspiration, whatever, but follow these directions if you received your A/D converter from TechZoneCommunications)

For information on the Firmware, and to download the firmware file, see TechZone_Thermocouple_Firmware page.(coming soon)

This photo shows the 4 pin connection used in the Thermocouple A/D
This photo shows the single wire connection.
The four pin connector is connected to the four pins on the mainboard as shown in the photo on the left and the single wire is connected into one of the ten pins in the old quadrature connector as shown on the right.


This is the thermocouple itself connecting to the A/D converter
This photo shows connecting the heater wires to the Extruder Controller, these leads are connected to the resistance wire in the tip of the extruder.
The picture on the left shows the thermocouple as it is connected to the screw terminals on the A-D Converter. The A/D converter itself is mounted somewhere on the extruder, to keep the temperature reading as accurate as possible, I try to mount it somewhere not directly next to the motor (the motor gets hot). It can be mounted with a small screw, a dab of epoxy, or with some hot glue.

Before turning on the heater, you need to make sure the thermocouple is connected with the correct polarity. To do this, load the RepRap host software and go to the extruder tab. It should be providing you with a temperature reading. If you put your finger on the tip of the extruder for a minute, you should see that temperature go up. If it goes down, then you have the polarity of the thermocouple reversed and you need to swap the wires.

The Photo on the right of this text, shows the connection of the heater lead wires to the Extruder Controller. it is the second set of wires from the right side of the 8 terminal block. This picture shows them as red and orange wires. They are not polarized (you can switch them places and it won't matter). I recommend not hooking these two wires up until you are ready to heat up your extruder tip. That should happen after you test all other aspects of your extruder and know that it works.


Here are some more photos to help with the details (a picture is better than any words I can create)


Using a standard thermistor

The two pins connected to the thermistor inputs on the extruder controller
The leads from your thermistor can be connected to the two pins, as shown in the photo. Polarity does not matter on this connection.


Connecting a Stepper Controller to Drive the Extruder Stepper Motor

Having hooked a stepper controller up to the extruder motor, and run it that way, I will never go back! It runs much more quietly, and seems to behave much better. I think that the reason for this is that the Extruder Controller is not designed to run a stepper motor, but has been "hacked" to run the stepper motor. Whereas, the Stepper controller is designed to run the stepper motor from the get-go. I found a description about how to do this somewhere (and I thought it was on the Wiki), but could not find it again to share with several of the TechZone customers who were interested in trying this... so I have created this section.

This photo shows the cable going from the SDA/SCL of the mainboard to the ten pin connector on the stepper controller, it also shows the wire used to enable the stepper controller
This photo which pins in the ten pin connector are used.
The process of connecting the Stepper controller to the Extruder stepper motor is fairly easy. Instead of hooking the SCA/SCL pins from the mainboard to the D9/D10 pins on the extruder board, you hook them to the step and direction pins on the Stepper Controller, as shown on the photos on the left and right (on the left, it is the cable that comes up too close and goes out of focus). You also need to connect the enable pin to ground on the stepper controller. I do this with a jumper wire from the max ground to the enable pin on the controller, it is the single yellow wire in the photos.

Polarity on the 2 pin wire is important, but if you hook it up backwards, it just won't turn the motor as it should and you can reverse the wire.

Connecting the power and the motor wires to the stepper controller is the same as it is on all of the Axis stepper controllers.

You can take a stepper motor from one of your axis, temporarily, and connect it in this way, to see how different your extruder performs. I think you will be pleasantly surprised.

Sorry for the less than clear photos, I will take some new pictures when I get my good camera back.