Control box rebuild

Progress on my first rebuild of my control box.
Initial photo shows what I started with on my 6040.
This is my first time wiring up anything other than a plug and never used solder before either so was a nice experience.
The 2nd photo which looks very messy was my first attempt at wiring everything and discovered I had two wires touching that fried a stepper motor.
The 3rd photo is me finished for now I've rewired the sheilded wires properly with heat shrink and a better job at soldering.
Thank you to you guys aswell for your input and advice.
Next step will be to wire the vfd to get mach3 controlling it.

Update I have a fault with the Y axis only going in one direction when jogging both left and right arrows.
I have fault tested all the wires, motors and different setups and pinpointed it to the breakout board itself.
initially I presumed it was my wiring so swapped the green connector plugs on X axis and Y axis and the result was X would only go in one direction and Y became crippled in movement. at this point I got confused and fault tested everything finding the motors, wires and drivers all worked perfectly when not wired to the Y axis pins on the breakout board.
I tried different settings on Y axis as well in mach3 thinking it could be a settings issue but no luck however I am no expert on mach3.
Does anyone recognise this issue or have any suggestions or is it possibly there is a physical fault with the pins on the breakout board?

other posts I have read have had problems due to faulty breakout boards
others have had problems with chinese copies of other manufactures usb motion controllers
Attachment 24214
going by your photo you may have to either try another BOB or connect the BOB to a PC parallel printer port

John

yeah I have the UC400 there floating above the Bob, I kinda new I was going to have to buy another BoB but was hoping it may just be a software fix :/

how many axis are you using?
I can only see 3 stepper drivers in your photo
If I am correct move the Y axis to the unused A axis on pins 8 & 9

this diagram is the result of reverse engineering a board to help another member
Attachment 24215

do you have an old PC with a parallel port you could use to test the BOB ?

John

When I had this problem (except with the Z axis) it turned out that the "direction" wire had come out of the drive. The drive thought that the direction was always the same polarity (whichever it pulls to) so the step pulses always made it go the same way. It happened just after I had done some mods to the unit that involved disturbing the wiring. Poked the wire in the term block, did the screw up properly, problem solved. The same thing would happen if the connection had come off at the BoB end of the link, or on the BoB itself. Trace it through before you buy a new BoB.

I tested the wiring but not the actual pins on the board, I will do that as well as try using the A axis pins.
question what would I be looking for when using a multimeter on the pins or should I say what are they meant to read if worked correctly? actually I could compare the other working axis to show what it should be so answered my own question there.
Also was thinking over the A axis swap method as JohnSwift mentioned, When I activate the A axis with 8 and 9 pins how do I make the system treat A as Y or do I put the Y pins 4 and 5 into the A axis?
Before I did have a parallel port with a previous BoB which did have all 3 axis working however I burnt that one out accidently so got the cheap one you see in the picture also I went for this BoB because it had the relays for controlling the VFD on/off and Speed control.

assuming you are using mach 3

I expect in ports and pins you have

X axis step = pin 2 , direction= pin 3

Y axis step = pin 4, direction = pin 5

Z axis step= pin 6 , direction= pin 7

if that is correct

change the Y axis to

Y axis step= pin 8 , direction = pin 9
then connect the " A axis " output terminals 8 & 9 to the Y axis stepper driver

John

Sorted, all axis are working now. Just need to finish figuring out the vfd part now. Funnily enough I know how to wire the spindle speed but the simple on off relay on the bob connects to ? on the vfd...probably staring right at the answer but can't see it.

great result you have control of the stepper motors sorted

the relay will connect between the common and the forward switch terminal on the VFD

in the VFD manual there is usually a diagram to wire switches for the manual control of the VFD and a remote potentiometer to control the speed

on a CNC machine the variable DC voltage from the potentiometer is replaced by the 0 to 10V output from the breakout board
and the relay replaces the forward switch

do you have a link to download the VFD ?
or post the make and model number to search for the manual

John

if your VFD manual has a manual remote control some thing like this -

Attachment 24225

you could connect the BOB like this

Attachment 24226

John

What I've found on the Web so far is for the spindle control it is as follows:
Com - GND
AN1 - 0-10v
X1 - pin 17
However looking at your diagram X1 (FW) is used for on off relay.
Here's what I have vfd end Attachment 24227
I'll try out your diagram, will getting the wires wrong do any damage to the vfd?

looking at your photo of the terminals
this is how I would connect to the VFD
with the forward on/off control being BOB's the relay controlled by pin 17
Attachment 24228


yes
the relay switches the VFD on in the forward direction
and is the simplest control with one switch
depending on the parameters set for input X1


you could have 3 switches
one for on / off

a second for forward that works in conjunction with the on /off switch

the 3rd being reverse that works in conjunction with the on /off switch

John

Hmmm whilst attempting to set up the VFD I have hit another snag and I am guessing its noise interference or which ever its called with the data cables. I am getting intermittent stalling on the motors and in one case when moving one axis another was twitching (all when manually jogging)
#BIGsigh

from your photo

Attachment 24229

its not clear what is connected to earth
I suspect from the little I can see
its just the metal enclosure and the screen on the cable connecting the stepper drivers to the chassis connectors to the motors

does the motion controller have an ethernet connection to your PC ?


John

yeah as its all in a wooden box the wires from the drivers to the motors are the only things earthed for the shielding.
If I ground everything would that help with the interference?

ok had done some reading and going to ground my components tonight and replace some wires with shielded wiring and see if that works as I've just read a few threads in regards to this issue and it all boiled down to shielding and earthing component's.

that will explain the problems

I can not see an earth connection to the VFD

John

Just a thought, I've got enough shielded cable for replacing the external leads to the motors from the 4 pin plugs via the control box, how do I ground this part of the cable or is it shielded via the internal wires that connect the drivers to the 4 pin plugs as I grounded them? do I attach it to part of the cnc frame?

with 4 pin connectors you would have to connect the earth / screen to the shell of the 4 pin chassis plug

and then the cable screen to the shell of the 4 way inline socket

John

Quote:

---

Originally Posted by john swift

looking at your photo of the terminals
this is how I would connect to the VFD
with the forward on/off control being BOB's the relay controlled by pin 17
Attachment 24228


yes
the relay switches the VFD on in the forward direction
and is the simplest control with one switch
depending on the parameters set for input X1


you could have 3 switches
one for on / off

a second for forward that works in conjunction with the on /off switch

the 3rd being reverse that works in conjunction with the on /off switch

John

---

Ha Ha I didn't realise you drew on the photo that makes a lot of sense now, thanks for the info.

I'm on a buzz atm with lots of thoughts of this and that, think I found my second calling in building electronics (1st being woodwork) though I have a long way to go in learning.
My thought was in regards to the main cables from the drivers to the motors, although it was fun cutting and soldering the 4 pin plugs I was contemplating to have a single cable (per motor) running from the stepper to the motor with no 4 pin plug then if needed to separate I simply unplug the green connecter block on the driver.
Is this a done "practical" option or do people just stick with the plugs.

if I remember correctly a post on cnczone showed a control box with the cable going through a strain relief instead of the more usual plug & socket

this has the advantage of reducing the number of joints

but the possible down side is damage to the driver if you to unplug the connector from the driver very often

while some of the problems are due to cheap copies of the green connectors being used (I can not remember the original manufacturer)

you will find examples burnt connectors in both cheep chinese machines and on the Leadshine 3nd883 drivers used by Tormach

Attachment 24248

http://www.model-engineer.co.uk/foru....asp?th=127744

John

Ok grounded the psu's and vfd, moved most of the power leads away from the data cables.
I was getting what I think is EMI interference across the motors as you can see on my links: one being how the motors misbehave and the second being how they are now after fiddling about.
Thoughts and opinions are appreciated.
https://youtu.be/kjhNMUz9mxchttps://youtu.be/nBLjlxwuPTQ

I was talking to a guy who does control electronics for a living and he suggested twisted pair on all data cables inside an enclosure as a better option to shielded.
Logical when you think about it as a wiring scheme which cancels interference is potentially more robust than one which tries to shield data cables from interference.
I'm giving it a go and it seems good so far ;-)

Hi all, I'm having another go at the control box to get rid of the gremlins.

My first attempt failed ended up killing my drivers and breakout board with a static discharge (so I've been told) so have brought a new container with a metal backing and have started from scratch a new design.

I have made a video in order for you to review and see with your experienced eyes anything that stands out as good/bad, criticism is all welcome.


https://www.youtube.com/watch?v=FL1fY_2_VPo

Hi There,

Nice looking box and work - Some ideas

1.) Fans - Try not have the fans on the same surface as the air will just go in and out across that surface you would want the air to go across the box as much as possible so maybe one on the bottom front into the box and one on top of the box - sort of how they do it on PC cases. you can always get a multi meter with a heat sensor to check your internal temps of the components

2.) EMI and Ground Loop - it's always difficult to know if putting so many switch mode power supplies close together will cause EMI issues. when you connect your table make sure you don't create ground loops. my machine is all aluminum and I was happily making ground loops all over my table.

Quote:

---

Originally Posted by Palletlad

Hi all, I'm having another go at the control box to get rid of the gremlins.

My first attempt failed ended up killing my drivers and breakout board with a static discharge (so I've been told) so have brought a new container with a metal backing and have started from scratch a new design.

I have made a video in order for you to review and see with your experienced eyes anything that stands out as good/bad, criticism is all welcome.


https://www.youtube.com/watch?v=FL1fY_2_VPo

---

Getting there control box all up and running now just need to wire up limit switches and vfd however discovered the fan is dead in the vfd... going to test the vfd and spindle tonight and see if it's functional and hopefully it's just a case of replacing the fan.

Can anyone recommend a specific vfd or seller of vfds.
I'm not looking at doing any metal work just hard wood at most on my 6040.
Is their particular specs I need to look for?

Glad you making progress:)