DSP controller / 24v-3A PS / 40 watt C02 PS / 5042 drivers

[drandolph]

I got the laser power supply working and the dsp up however I can't seem to get the stepper drivers to respond. They are showing power and I have pls+ dir+ ena+ run to the dsp. I was hoping you might be able to give me some insight into what I might be doing wrong. I'm using the 3amp 24volt power supply to power the 2-2 phase drivers and the DSP. Am I also suppose to tie the pls-/dir-/ena- together? Am I suppose to supply +5 to the dsp in on the x/y inputs? I think I've read the DSP manual fairly well however I have no reference for the 5042 stepper drivers. I am following the drawing in the "DSP TYPICAL MINIMUM OPERATIONAL CONNECTIONS" PDF file pretty tightly. The stepper motors I'm using are nema 17 motors i harvested from the ebay special (40watt laser engraver) and from my research they are the .8 amp motors which is why i think the 3amp supply should be enough. Also the stepper drivers i received were labeled 2m542 i am assuming they are the same as the psd5042-2p driver and the pinouts and the markings seem to match.

Anyone got any thoughts on my stepper motors not stepping?

[Tech_Marco]

See the specification of the driver (2M542)
viewtopic.php?f=16&t=236

You don't need to provide 5V for the DSP as it's now running single voltage 9V~32V DC
The home switch X,Y can be common ground or common +5V. Common case is "common ground)

Did you power the stepping motor driver by the same PS (24V dc)?
24V 3A seems not good enough. You better switch to a bigger PS. Remember, everything consume current, not just the motor. The DSP may take 1A, the driver may take 1A (x2), and two motor 1.5A (x2). So... you need min 6A! So, I'll get a 24V 7A or bigger power supply to ensure stable operation.

[drandolph]

So tonight i tried to see if i could install the drivers and hook up the dsp to my computer, well every time i plug in the usb it trips the my GFI breaker.

I pulled everything off except for the power supply and the DSP controller and board and every time i hook it up via usb it still trips, as long as i dont have it hooked up the display and menues work. as for the power supply i have 1 24v 5AMP power supply and the motors im working with are less than 1 amp so i figured that should be enough but i have an extra 5amp ps as well and that didnt help when i used that to power the motors and left the dsp on its own. Any thoughts?

[Tech_Marco]

You better check your power supply and make sure it's well grounded. The DSP will NOT cause a breaker trip. When a breaker trip, it means that there is leaking from the (L) to the case. Or you may reversed the L and N by mistake. Or in other works, the DSP already got killed!!

I don't mind to switch another DSP but if it happen the second time, I'll charge for repair fee as all our DSP card have been QC before shipping. Make sure you use a qood quality power supply. Cheap switching Power Supply will give you a big headache. FYI, use a digital volt meter to check voltage in between the L in referrence to the case see if you get some reading.

Again, get a quality PS!

[drandolph]

hehe, out of humor i bought all my power supplies from lightobject so i hope they are quality and from what I've seen they have been and the response to my questions have been great.

I thought i might get a little multimedia going on so you can see my problem driving the steppers.

http://www.youtube.com/crandolp#p/a/u/0/Q8HR9MS5Owk

[Tech_Marco]

You made me dizzy by watching on your video...you moved too fast!

By the way, no need to connect a 5V to the DSP card. Plus, the connection to the laser is 134, not 124 as it got changed a little (I need to update that drawing from my customer who made it for me).

I'll take some 'anti dizzy' pill and will go through the video see if I can find out the problem.

BTW, my 24V 15A PS is good!

[drandolph]

I'll make you a deal once we get the stepper drivers working I will draw it up in full detail for you and post them here.

[drandolph]

OK I got it instead of following the drawing I followed the actual manuals and figured out that on the driver to ignore the enable and to hook up the dir and pulse and ignore the part where it says ignore the negate terminals of dir and pluse. Really simple and easy to understand as long as you do read the directions

Basically
PLS+ goes to PWM+
PLS- goes to PWM-
DIR+ goes to DIR+
DIR- goes to DIR-
ENA+ is not attached
ENA- is not attached

[Tech_Marco]

I got a reply from my test engineer. See picture, it's the correct connection for the DSP and the 542 driver
You can pick one of connection and it should works fine (see the 3rd picture).

Yours seems wrong,
PLS+ goes to PWM+
PLS- goes to PWM-
DIR+ goes to DIR+
DIR- goes to DIR-
it should be:

PLS+ goes to PWM-
PLS- goes to PWM+
DIR+ goes to DIR-
DIR- goes to DIR+


So, the power tripping got it fixed right. Ground problem issue, very common!

[drandolph]

weird ill try it his way and see if it behaves any differently. However onto my last and final question. I also have the 200ma digital meter from lightobject and when i hook it up to the laser tube to measure the current it gives me an accurate reading but when i fire the laser it latches open and the panel goes blank until it reboot. the whole time the laser is firing and the meter is reading correctly. Do i need to put a cap in between or is there something i'm missing? Thoughts? After i figure out this last detail I'll do up a nice little drawing.