Chinese CNC 3040 Spindle speed control

Hi Guys,

Very first post as I just got into this CNC stuff. As most do, bought a chinese 3040 off ebay, think the 3040T-DQ. No experience with this stuff before, but done quite a bit of research as I was going to build one myself, but for the price I paid, I don't think it is that bad. Not had a problem yet ..

BUT ....

I am trying to get Mach3 to control the spindle speed. Opened the controller box, have 2 green boards, the JP-382A controller and the JP-1482 "spindle" card. Now, I have noticed the main board as PWM-OUT (but doesn't specify which pin is which). I have tested with multimeter and noticed that when I set my spindle speed in Mach3 lower the voltage drops over two of the pins and full speed, I get about +5V over the same two pins, so something is happening, but when connecting to the spindle boards' PWM input, I assume, it doesn't drive the spindle at all. I can only manually do it. I know other models come with a H and A switch to enable software control or something which mine doesn't have, but I am sure it must just be a jumper somewhere?

Anyone successfully controlled the spindle speed in Mach3 with the boards mentioned above before ? Would love to know how you connected and configured it up, if it can be done at all ?

Thanks !
Andre

Hi Andre,

I have been asking about the same thing on CNCzone

I have had some response, link below.

Newbie Enable PWM on Controller.

There does also appear to be version of this control box with a switch on the back, but I don't know if this uses the same circuit boards.

If I find anything further out I will let you know.

Regards

John

Quote:

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Originally Posted by m0ng00se

Hi Guys,

Very first post as I just got into this CNC stuff. As most do, bought a chinese 3040 off ebay, think the 3040T-DQ. No experience with this stuff before, but done quite a bit of research as I was going to build one myself, but for the price I paid, I don't think it is that bad. Not had a problem yet ..

BUT ....

I am trying to get Mach3 to control the spindle speed. Opened the controller box, have 2 green boards, the JP-382A controller and the JP-1482 "spindle" card. Now, I have noticed the main board as PWM-OUT (but doesn't specify which pin is which). I have tested with multimeter and noticed that when I set my spindle speed in Mach3 lower the voltage drops over two of the pins and full speed, I get about +5V over the same two pins, so something is happening, but when connecting to the spindle boards' PWM input, I assume, it doesn't drive the spindle at all. I can only manually do it. I know other models come with a H and A switch to enable software control or something which mine doesn't have, but I am sure it must just be a jumper somewhere?

Anyone successfully controlled the spindle speed in Mach3 with the boards mentioned above before ? Would love to know how you connected and configured it up, if it can be done at all ?

Thanks !
Andre

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You guys find any more info on the PWM control for these boards? I have the exact same boards in my 3020T-DJ that i just got.

Nevermind, i think i got this figured out... I will post about it shortly...

Quote:

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Originally Posted by kb0nly

Nevermind, i think i got this figured out... I will post about it shortly...

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That's great news - look forward to your post. I spent a couple of hours on trials without any real success.

http://www.cnczone.com/forums/pcb-mi...l-jp-382a.html

I got the spindle on/off control working, still trying to figure out the PWM speed control, i just have to figure out how to enable it once hooked up. Seems like the front panel pot needs to be removed and something jumped like on the other models of these, still working on it!

Like kb0nly, I been working on the problem of trying to get PWM spindle speed control with systems that use the JP-1482 and JP-382A boards. Unless someone can tell me differently, I am of the view that it can't be done without additional circuitry.

Having decided that this was the case, I set about producing a small board (about 2" square) that sits between the original controllers. Whilst it is still under development, I have had some success. Currently I can read the PWM signal from Mach3 and produce numbers varying from 0 to 255. The importance of this is that I can use these numbers to control a digital rheostat. This component is the digital equivalent of the spindle speed control found on the controller front panel.

I haven't connected the rheostat yet as I've had to order it from a supplier and I am still waiting for it to arrive. That said, I hopefully will be able to test my ideas out in full during the next few days. One of the nice things about my board is that it does not require any alterations to the original controllers. Additionally it should be cheap to make - I'm guessing about £10 (approx $15).

Now this is where I need some help. I'm a complete newbie to CNC machines so please excuse me if this is a stupid question. I want to know what would be the maximum acceptable step change in spindle motor speed. For example, if the motor speed could only be changed in 100 rpm increments, would this be acceptable on a table top machine like the 3040? If not, what would be OK?

Thanks for reading this. Any advice from more knowledgeable forum members gratefully received.

Ignore this reply. Its mistake.

Not been any posts on this thread for a while, Has any one solved the PWM problem with the JP 1482 board yet.