replacing burned cnc breakout with new, help in pinout please

Hello,

I own a hobby cnc machine from China called HY3040 and you can find a lot of them on ebay, but non of them have similar controller boards inside. Each comes with different ones and usually when you first buy them, they come with cheapest boards you should anyway change it. In my case I have to, because the breakout is burned.

I must search to find a good board but for now to put the machine back to work I have another cheap one available which also got off ebay.

Now to replace the burned breakout board with the new one, I have two main problems:
1. no documentation!
2. knowledge insufficiency

Generally, I know that there are control wires S,N,D,E between the breakout board and the controller board per axis, and from there each axis controller board is connected to the stepper motor with A+ A- B+ B- wires. Here inside the control box I found strange wiring to me. With some more knowledge I could easily trace and connect but I found it better to not to do trial / error but to turn to specialists in the forum.

Chinese seller sent what he calls "manul", but in that there is a little information about a different breakout board than what is inside the machine control box!

I attach photos of burned and new boards. As you see on the photo of the burned board, a double-row 20P cable connects the main motor controller (which has 3 motors connected to for A+ A- B+ B-) to the breakout. Beside table there is a pinout printed:
BS, BD
NC, RL
XD, YS
XS, YD
XE, YE
AD, ZS
AS, ZD
12, 12
GD, GD
VC, VC

Questions:
1. On the burned board there is nothing written around the motor wires socket at the side of the board, but I guess that those wires are XE, XD, YE, YD, ZE, ZD, how could I be sure please?

2. As first step I only want to put X axis to work. On my new breakout board, I have XE, XD, XS, XN pins and X-Limit with 2 pins totally 5 pins. On the old board I have 2 pins connected directly to the motor, and 3 ones (XS, XD, XE) connected by the 20P cable, also 5 in total, but how should I connect them correctly and what I have to measure / know?

The photo with my fingers in, shows the burned motor! The photo with pins information written around, shows the new board.



Please guide me.

It would be easier to replace the power transistor.

The crater of exploded epoxy looks like it had a spectacular short circuit somewhere. Was it in the line of duty?

SunnySkyguy said:

It would be easier to replace the power transistor.

The crater of exploded epoxy looks like it had a spectacular short circuit somewhere. Was it in the line of duty?

Click to expand...

Generally true but not at current situation: I just came to this city, still waiting to receive my baggage from post! I even don't have a soldering iron and I don't know a single shop where I can get the power transistor, but I have the new breakout board in 10cm of my hand and so it is easier to find out how to wire it.

Up to know I learned that to test x-axis for the new breakout board, I must connect XS, XE, XD, GND to the P20 cable. What I don't know is the pair wires that go directly from the breakout board to the motor cable.

I traced wires and I see that they are not going inside the motor! near the Z-axis motor, those z-pair wires are taking another way inside the machine and I guess they are simply for a limiting switch, so that the motor stops at extends by touching the switches. I did a signal trace and I see that each pair is connected both to itself, to all others and connected to GND.

If any idea or further suggestions for tracing / measurement to make sure, please tell me.

I think I'm close to replacing it finally!

Thanks.

That power transistor MIGHT have failed because the adjacent capacitor has gone short circuit. The replacement board does not seem to have these components on it so it is unlikely to provide the same functions. I.E the original board is supplied with unfiltered DC and the two power transistors then regulate this voltage to a smoothed DC suitable for the micro. So, as these components are not on the new board, it expects to receive already smooth DC voltages.
Frank

Thank you everybody,
I already replaced boards and happily all my guesses were correct :-D

Chuckey:
On the top left side of photo of the new board, near the LPT1 port you can see the usb jack and the switch beside it saying that the board receives +5v either from the usb or an external source. The +5v socket is at the other side of the LPT1, the label of which is barely seen on the photo. So you are absolutely correct. Thanks.