[RicksCNC]

Hi
A good friend Nicolas Forwood suggested me to come here and address All_the_Man for this problem.

I have a leafboy77 alias AKZ250 mach3 breakout board, and cannot get the zero touch plate to function.
I am running a 48v 12.5a Power Supply, to drivers, BOB is powered through USB, 5v output and grounds.
Tried connecting to 5v from board and the spindle is grounded but cannot get light on on BOB nor signal touching spindle.
Tried connection to 48v with resistor as identified on page 36 in pdf or page 70 as show at bottom of page.
(Maybe the wrong resistor?) Dont dare go too far as I fried a few circuits in the past.

I will include as attachment the manual for this board hoping you can help me resolve this mystery.
I've searched internet and many forums but to no avail on what the problem may be.
To set thingd with no surprise, I've constructed my own CNC running nemas 23 425oz motors, on KL 8056 Drivers fed through Leafboy77 BOB
Spindle is GDZ-80- 2.2B Water cooled 2.2k, under a KR200 inverter, which I will need help with later.
My knowledge in electricity and electronics is + - on a Battery.

Any help you can give will be greatly appreciated.

Best Regards

Rick

[mactec54]

Hi
A good friend Nicolas Forwood suggested me to come here and address All_the_Man for this problem.

I have a leafboy77 alias AKZ250 mach3 breakout board, and cannot get the zero touch plate to function.
I am running a 48v 12.5a Power Supply, to drivers, BOB is powered through USB, 5v output and grounds.
Tried connecting to 5v from board and the spindle is grounded but cannot get light on on BOB nor signal touching spindle.
Tried connection to 48v with resistor as identified on page 36 in pdf or page 70 as show at bottom of page.
(Maybe the wrong resistor?) Dont dare go too far as I fried a few circuits in the past.

I will include as attachment the manual for this board hoping you can help me resolve this mystery.
I've searched internet and many forums but to no avail on what the problem may be.
To set thingd with no surprise, I've constructed my own CNC running nemas 23 425oz motors, on KL 8056 Drivers fed through Leafboy77 BOB
Spindle is GDZ-80- 2.2B Water cooled 2.2k, under a KR200 inverter, which I will need help with later.
My knowledge in electricity and electronics is + - on a Battery.

Any help you can give will be greatly appreciated.

Best Regards

Rick

The first thing to check is the 4th pin in the spindle connector to see if it has Ground continuity to the spindle body, most don't and this will need to be corrected

[john-100]

Hi Rick

I don't see your link to the manual

this manual I have downloaded
Attachment 396854

as a diagram for a touch probe I think your using on page 36

the dropper resistor between the +48V and the boards input should be 6800 ohms (6K8)

this limits the current into the AKZ250input to a little over 6mA

so the 330 ohm resistor on the board will drop about 2V
leaving 3V to power the LED indicator and the LED inside the opto isolator

Attachment 396856
the boards input circuit has been added in green

if you have used a 6K8 resistor and connected the probe correctly

you should measure about +5V between the input and board ground terminal
the LED indicator should be "on "

when the tool touches the isolated plate the LED will go out

Mach should see the input go from a logic high (1)
to logic low (0)


John

[RicksCNC]

Hi John

Thank you for your quick response.
I'm not as quick, but I get there

Went and purchased 6K8s and setup as per your instructions...
Connected to board ground and no light or any reactions at all.
Setup mach3 with the autozero button, button replies, but no signal if positive touched to spindle.
The spindle ground it active to the body.
If ground comes from the Power supply, then I get a so very faint light,
if I touch the wires together as if grounding the olate I get a little bit more light on the board
and if I rub the wires together then the light on board gets a little brighter yet bit never to its full light potential
Any connection type does not activate the digitize led in the diagnostic panel in mach3
I measured DC from pin 2 on board to ground on PS and fluctuates from 0.14 down to 0.02-0.01 ans stays at these readings, same at end of wires.
So there you got it.
No Idea why it doesn't work
I'm stumped!

[john-100]

I assume you are using a simply touch plate from the likes of Ebay

do you have a wire connecting the negative 48V power supply terminal to the AKZ250 input ground
and a separate wire with a crocodile clip to the tool ?

re arranging your diagram
Attachment 397032

John

PS
going back to post 1

what value of resistor did you use ??

[RicksCNC]

Well John, Post 1 I had a 330 because I was told where I purchase it that that's what was needed looking at the schema page 36
So yes I had the wrong resistor.
Looking at your remake of my connections, Call me chicken but, my setup is exactly as on page 17 leafboy manual, and
What worries me, (not putting you in doubt in any way) is putting 48V to the ground where the drivers are grounded since the whole card is powered 5v through the USB cable?
Should I put a 6k8 on that side also? or use a gnd from the other side of the card near the PWM?
I don't understand very much about electronics, so I have many questions as how it works.

Thank you for your patience.

Rick

[john-100]

using a 330 ohm resistor and 48V DC would be a bad combination

if you connected it as in your diagrams in post 4
the lack of a connection between the negative 48V supply terminal and the input ground terminal
will of saved the AKZ250 input from damage

I don't see a link for the manual in your original post

in this manual

Attachment 397178
which wiring diagram did you follow ?


if you followed the one on page 36 in this

Attachment 397178
you could use a low power regulated 5V power supply ( 5V @ 100 to 200mA) and 330 ohm resistor



note - not all 5V phone chargers are regulated !!!

John

now I just need to find out why my usual browser has stopped working with cnczone
Microsoft edge works OK