Messages

11

SmoothStepper USB / Re: How to use closed loop spindle rpm with SS

« on: October 21, 2010, 12:30:11 PM »

That's precisely my problem, DC motors are by nature not linear. So there needs to be some way of adjusting pwm linearity not just max/min like the doc you linked to suggests. I tried to use the caibration screen but as soon as I click AutoCal my spindle turns off and mach goes into an EStop condition and calibration stops, not sure if that's because AutoCal thinks it's done and just powers off the spindle (having not done anything) or if something is screwy because i'm using an SS.

My original question was same as one from thosj, the index signal doesn't seem to "correct" mach 3's pwm output based on the actual rpm being reported vs rpm requested.

btw, thanks jeff, I've actually read that doc you've linked, and there was a lot of info in there that I needed to get this far.

12

SmoothStepper USB / Re: How to use closed loop spindle rpm with SS

« on: October 21, 2010, 11:58:00 AM »

Yeah, I've tried every combination of those checkboxes under spindle setup and mach just ignores them, or at least I see zero effect.
spindle rpm will show 2500 in the DRO for example but mach has been asked to do 2000 and I see zero adjustment in pwm to get it to match.

Eugene

13

SmoothStepper USB / How to use closed loop spindle rpm with SS

« on: October 20, 2010, 05:37:12 PM »

Hi guys,

I've got my spindle operating in PWM output mode from mach3 with SS, and I have an opto-interrupter reading from a single gap wheel for rpm feedback to mach3. I can control rpm from within mach3 and I see a readout show up. Currently I'm trying to setup closed loop operation but I'm unable to make it do anything (it's just ingoring any settings in the section). Any suggestions where I can try to look? or does the SS not support closed loop right now?

Thanks

14

SmoothStepper USB / Re: SmoothStepper died

« on: October 09, 2010, 12:35:35 AM »

Greg, I took the measurements from the little case around the USB plug.

As for my whole configuration, I figure there's really no need for me to externally power the SS, was just doing it because I thought I could, no need to really as I'm going to be plugging one port into the G540, and the other into an externally powered break-out board. So I don't see why I can't just leave it running off my USB connector.

If I decide to power it I'll order one of these: http://www.soigeneris.com/MeanWell_PS_05_Power_Supplies-details.aspx

15

SmoothStepper USB / Re: SmoothStepper died

« on: October 08, 2010, 08:40:20 PM »

Thanks for clearing that up Jeff.

So I took some measurements of the voltages:
1.2v -> 1.350
2.5v -> 2.653
3.3v -> 3.434

do these seem out of whack?

btw, I used an IR thermometer and the hottest chip is the the middle one of the row of 5.

Also tried a different USB cable, same result.

16

SmoothStepper USB / Re: SmoothStepper died

« on: October 08, 2010, 06:06:36 PM »

Thanks Greg, I'll take a look later today when I get home from work. I did check some of those volts and they seemed a tiny big over what the silk screen said, like the 3.3 was at 3.5, and the 1.2 was at 1.4 or so. But I'll check them again and let you know here. I'll also try testing with a different DVM or my scope for more precision.

PS: What's the real point of powering the SS from the +5 header and not usb? Is it just for using smoothstepper to power break-out boards that require more than 500mA? Also, as a 2nd side note, under what circumstances would I want to ground it, I thought it was to eliminate ground loops (grounded all of my power supplies at the same point)

17

SmoothStepper USB / Re: SmoothStepper died

« on: October 08, 2010, 05:09:01 PM »

Well, that's the crazy part, the SS shows up in device manager and is detected by mach3, but then fails to communicate properly while at the same time getting warm at that one chip.

I'll check out the 5V output of my power supply with a scope to see if there's significant noise, or spikes.

Thanks

18

SmoothStepper USB / SmoothStepper died

« on: October 08, 2010, 12:30:35 PM »

Hey guys, I recently got my smoothstepper setup and I love this thing, it made my cnc machine so much better. I could now get faster rapids and it just seems to be smoother overall. However in the process of building an enclosure for all of my electronics I somehow killed my smoothstepper it seems, here's what happens.

I'm powering the SS with USB +5 and Mach 3 won't communicate with it, the red and blue lights stay lit. I get an error that a timeout has occurred and then after a few messages it tells me that there was an error communicating with the CryptoMemory. I've tried computers thinking it might be a driver issue but same result on all of them. I noticed something interesting though, after a couple minutes of being powered up a chip next to port2 gets warm. I check around the port for any debris that might be shorting it but there's nothing there.

The only thing I can think of that could have burnt out the board is that when I first had it wired up inside my cabinet I was supplying +5v from an external power supply, I measured its output at 5.26v, coming from an ATX computer power supply. And had it grounded to the chassis of the cabinet (the grounding jumper enabled).

Thing I can't figure out is that the input voltage was good, and I measured for any stray potential between the floating ground (coming from power supply) and the ground of the case and there wasn't any.

Thanks for any advice here, I'm just trying to figure out what NOT to do when I get the next SS.