Messages

421

General Mach Discussion / Re: Has anyone actually got a C11 to control a KB speed control via Mach?

« on: July 05, 2012, 01:25:56 PM »

Thanks John, I can't tell you how much your knowledgeable input is appreciated!  I do OK with auto DC circuits and simple electronics but for some reason the verbiage in the C11 (and C6) manuals re: speed control hookup zings right over my head.

Yes, I have a completely separate 12VDC 1 amp power supply connected to the proper 12V inputs on the C11.  If I connect a voltmeter across the Gnd and 0-10V outputs on the C11 with nothing else connected, I get varying voltages corresponding with various S commands from within Mach.  To my way of thinking, that verifies that the P/Port pin hookup and the config settings in Mach are OK.  It's just getting that varying voltage connected to the KB in a way that makes it happy is the problem.

My simpleton logic tells me that if the KB works properly with 3 wires connected to a pot, there should be 3 wires going to the C11....BUT the C11 outputs a variable voltage, not a variable resistance; so there goes simpleton theory.   Don't they have a correspondence course for that?  "Simpleton Electronics Theory"

422

General Mach Discussion / Re: Has anyone actually got a C11 to control a KB speed control via Mach?

« on: July 05, 2012, 09:21:58 AM »

John, I'm not electronically savvy enough to follow what you've said above but thanks for the input.

I have a KBIC-120 controller.  I would think all the KB's of that basic design share the same pot connections and operation.

The C11's speed control output is definitely DC, adjustable between 0 - 10V.  The C11 manual specifically states that it will control KB and similar type DC motor speed controllers by replacing their manual pots.  There must be something I'm missing in the hookup & calibration.  I emailed Arturo again yesterday so hopefully he can clear up my ignance.

423

General Mach Discussion / Re: cnc4pc c35 bob w/spindle control question

« on: July 04, 2012, 09:39:00 AM »

You can do threading with just the C3 but the spindle speed would have to be controlled manually at your VFD.

If you want to control the spindle speed from within Mach you'll need a the C6.  I have a C11 which combines a B.O.B. and speed control and I also have a C3. The C3 works great but so far I haven't been able to get the speed control portion of the C11 hooked up properly and working.

Good luck and make sure to post details if you get a C6 and get it working.

424

General Mach Discussion / Re: Has anyone actually got a C11 to control a KB speed control via Mach?

« on: July 02, 2012, 08:49:10 AM »

I'll definitely pass along any info, good or bad.

I've decided to back off the speed control issue for now since further uneducated fiddling around may let out some smoke.  I still have a lot of mechanical chores to work on to get this lathe up & running and manual speed control via manual pot will do fine.

I emailed Arturo a couple weeks ago and it must've gotten lost or he's on vacation...no biggie.  I'll try him again later.  He's been quick with answers previously.

Thanks,

Milton
Collierville, TN

425

General Mach Discussion / Re: Has anyone actually got a C11 to control a KB speed control via Mach?

« on: July 01, 2012, 10:58:32 AM »

I may have posted this in the wrong section since it's probably not "General Mach Diccussion" related and is a hardware question.  Should it be moved to another section and if so, how do I do that?

Thanks

426

General Mach Discussion / Has anyone actually got a C11 to control a KB speed control via Mach?

« on: July 01, 2012, 08:45:34 AM »

I must be a complete idiot because I can't.  I have Mach neatly switching the KB power on & off via M3 commands or clicking the onscreen "spindle" button.  If I leave the manual pot connected, the KB varies the speed of the Baldor 3/4 hp motor beautifully (yay KB!)  If I take off the pot & connect the C11 to the KB, the motor instantly spins up to a much higher top speed with no control via "S" commands.  No Mach config changes make any difference.

The C11 manual (to me) is vague but the C6/KB hookup section has more verbage on hooking up to a KB and I assume the 0-10V analog circuits are the same in the 2 boards.  My interpretation of the C11 instructions is that the pot is to be removed and the C11 0-10V analog outputs connect to the P1 & P2 terminals on the KB which leaves the P3 terminal open.  The C6 instructions (pasted below) to me imply that the outputs are connected to the pot terminals.  Can that be true???

"These are the steps for replacing a potentiometer:
1. Measure the voltage difference between P1 and P3. Make sure it measures
under +12vdc.
2. Fine tune the analog output to the output voltage you got from step 1.
3. Connect the ground from the analog output to the ground of the
potentiometer (P1).
4. Connect the analog output to the wiper connection of the potentiometer
(P2).
If the reference voltage from pot is between +10 and 12vdc, you can use it to
power the analog circuit (not for the C6, because the relays might draw too much
power). In this case, connect P1 to the ground of the power terminal, and P3 to the
+12vdc power connector."

I checked the voltage across the KB P1/P2 terminals with the pot attached & turned up to max, motor running at full chat and get 3.5VDC.  I checked the voltage at the gnd/0-10V outputs on the C11 (with nothing attached) and it varies up & down in concert with varying S commands from Mach.  I set it to 3.5V max with the onboard trim pot.  I know, not what the inst says but I had to try something to slow things down!

When the pot is removed from the KB and the 2 leads are connected from the C11, the voltage across P1 & P2 is locked on approx 6.5 volts, no matter what is commanded by Mach.

Somebody please smack me up side d'head and clear up my stoopidness!!

427

General Mach Discussion / Re: CNC4PC C11 question

« on: June 17, 2012, 10:19:50 AM »

Answering my own question feels kinda dumb but in case anyone else is down at my level of electronics savvy and has a similar question here's what I did.  (Some other clueless person may spend hours searching for "CNC4PC C11 relay hookup" like I did trying not to let out the magic smoke.)

I configured Mach to tell the C11 to switch the relay on & off via Pin 1 and sure enough, the "NO" connection and the V_IN2 measured open with an ohmeter when the spindle was off, then the relay clicked and the terminals measured closed circuit when when the spindle was clicked on.  I connected the external relay's 24VDC power feed across the terminals and it works perfectly.

428

General Mach Discussion / CNC4PC C11 question

« on: June 15, 2012, 12:18:24 PM »

Hi there, esteemed CNC gurus.

I am retrofitting a Denford ORAC lathe and have a couple of CNC4PC C11 B.O.B. questions.  I emailed Arturo who is usually extremely quick but I guess he’s on vacation and I haven’t heard back yet.  I’m hoping to get the spindle on/off via Mach going and then proceed on to speed control.  The ol’ eat the elephant one bite at a time applies here.

I have it installed and working as far as the stepper motors go.  I have the control PC’s USB connected to the C11’s supplied USB 5V power cord and am using a converted PC power supply for the other 5V and 12V connections.

Does the C11 require that one of its onboard ground connections be connected to the machine's central ground point?
 
I want to use one of the C11 onboard relays to switch power on & off to the 24VDC coil in a separate larger relay that switches the 110VAC power to my DC motor speed control.  I must admit I'm confused by the manual and various wiring docs on the website.  It’s probably just a lack of electronics terminology knowledge on my part.

If I have +24VDC going "in" to my large relay's coil, do I just connect the other side of the coil to the "NO" connection on the C11 and the V_IN1 to the -24VDC wire on my 24VDC power supply?  I know I’ll have to configure Mach to supply a pulse to the C11 via pin 1 or 16.

429

General Mach Discussion / Re: Toolpath display question in Turn

« on: January 14, 2012, 12:13:50 PM »

Could you possibly have X and Z mixed up?

I don't think so.  X in the minus direction moves the tool towards spindle centerline, Z minus moves the tool towards the chuck.  That's correct, yes?

I just figured it was because the toolpath screen was referenced to X0 always being spot on spindle centerline.  Siince this part has X0 about 1/2" away from center, it looks funny.  The path was fine and the part was successfully modified.  It's a model helicopter engine cyl. head "button" that needed .048" removed from the 6 deg "squish band" portion and .048" from the flange where the cyl. seats to reduce combustion chamber volume/increase compression ratio.  Just a series of roughing/fine face cuts on an angle followed by a move over then the facing rough/fine cuts on the flange.

430

General Mach Discussion / Re: Toolpath display question in Turn

« on: January 14, 2012, 11:19:53 AM »

Don't laugh at my primitive coding; it worked and made me a few dollars.