Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: DICKEYBIRD on July 01, 2012, 08:45:34 AM
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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!!
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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
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I think its fine here, more chance of people seeing it. You may however get a quicker response from Arturo.
Hood
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Not me but I'm attempting the same scenario.
Waiting now of replacement chips for the c11 from Arturo. Seems he's out of stock on one particular IC needed for the set but he didn't say when it was due to come in.
On hold for now. Once I get things running I'll let you know how mine is setup.
Actually now looking into the Gecko 540 and a higher Amp & Voltage power supply too.
I may disband the whole cnc4pc thing. Well see.
If you get it figured out before me, I'd appreciate the reciprocity of the details!
Vogavt
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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
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Which KB controller are you using? On my Novamill I have a KBWM240 running a Baldor .5 hp motor, but as far as I can see the KB controller's pot must be floating around relative to earth since there is no transformer or dc-dc converter inside the KB to isolate it from mains voltage. I decided that in order to control the speed from Mach 3 I will need to opto-isolate the variable duty-cycle output and smooth it on the "KB" side of the isolator. If you try connecting direct, goodness knows what is happening.
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I decided that in order to control the speed from Mach 3 I will need to opto-isolate the variable duty-cycle output and smooth it on the "KB" side of the isolator.
"Opto-isonlate" Are you saying that you need another board? The c11 has that already.
"smooth in on the KB side" How?
Sorry I not the brightest when it comes to electronics (except when that dreadful flash of brightness happens, and in my case it usually means a bad thing if you get my drift). LOL!
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John, I'm not electronically savvy enough to follow what you've said above but thanks for the input.;D
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.
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Well, apologies that I wasn't familiar with the C11 BoB when I first posted. On looking at its manual (which is not entirely clear on this matter) the 0 - 10v output is internally opto-isolated, that is, it has two outputs between which it will output a voltage variable in this range, and these outputs are electrically isolated from ground so they can safely be connected to the KBIC.
Looking at the KBIC manual, I think it is essentially the same as my controller except that mine comes in a metal box with control pot and mains switch. However these controllers are NOT grounded, so the "0 volts" line at one end of the pot will be bouncing round at up to mains voltage, hence the need to opto-isolate the control input.
For the C11 to generate that isolated 0-10v ouput, it has to have an internal source of more than 10 volts that is itself isolated from ground, and I think it must have an internal floating dc-dc converter incorporating an isolating transformer to do this. The C11 manual does say that for the function to work a +12 volt 20 mA supply for the function to operate (see page 15), which would be supplying the on-board converter. Do you have this supply connected? If it isn't then you would get anomalous behaviour. See page 18 of the manual for where to connect it. As far as I can see all the rest of the C11 only needs a +5 volts supply. If you need to generate +12 volts then a small regulator off the stepper motor supply should do it. My BoB on my lathe runs from the stepper supply (about 40v) which it reduces to 12v then 5v.
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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. ;D Don't they have a correspondence course for that? "Simpleton Electronics Theory" ::)
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I just found this datasheet on a (now discintinued) KB Electronic Potentiometer that I suppose performs a similar chore as the C11 only with pushbuttons to do the up/down speed commands instead of Mach inputs. To ye of the Society of Magic Smoke Tamers it probably means something but to me not so much. It connects to the F+ & F- terminals as well but I thought they were field connections for wound field motors, not PM motors as I'm using.
http://www.a-aelectric.com/pdfs/KBEP240d.pdf
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Geez, can this be simply a case of "Should'a RTFM?" From the KBIC manual:
"The output of the control is a linear function of potentiometer rotation. The KBIC®
can also be operated in a voltage following mode by supplying an isolated analog signal (0-7 VDC) to the
input terminals P2 (+) and F-. If an isolated input signal is not available, the optional Barrier Terminal
Board Signal Isolator (SI-5) can be used."
So, this means I should adjust the C11 on-board trim pot to 7V, connect the Gnd and 0-10V terminals to the P2 and F- terminals on the KB and Robert is my father's brother?
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Dickeybird,
In a moment of frustration on getting this to work, a couple of weeks ago I connected to the F+ and F- to my KBLC-19m. Huge flash! Huge!
Don't do this. It's reported elsewhere that at least on one of these board there's some faulty information.
It blew one of the traces completely off the KBLC-19M board. I resoldered it with a small shielded wire, then connected it to the A+ and A-. When I applied the power to the KBLC-19M with it back to "normal", it blew yet another set of traces!
This board is seriously hosed up and only good for parts (maybe).
Luckily, I'd bought two KBLC-19M's at the same time. I wasn't planning on having it as a spare; I wanted it for setting up my lathe.
Make sure you know what you're doing. Get some help.
In my case, I needed help..... professional help, because I dumped my cauldron of magic smoke! ;D
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Normally, two wires from the KB supply +12 v and 0 v to the ends of the pot track; and the slider picks up a variable voltage between 0 and 12 v depending on its position. What the KB needs is a voltage at something between 0 and +12 v relative to its own 0 v supply, which is what the C11 supplies. The problem is that the 0v in the KB may be waggling around relative to the ground of the C11 which is tied to "mains" ground, by up to +/- 250 volts, because of the way the KB controller works (I think).
So the question I would ask is whether your separate 12 volt supply shares an earth (or common) connection with the C11? Assuming that it's connected to the appropriate pins on the C11, it may be that its -ve ouput is connected to mains earth which will also be connected to the common connection of the 5v supply. I think that to work correctly the 12 volt supply may need to be completely isolated from the other supplies. In my reading of the manual it is very vague on all of this.
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Hi John, I'm using a separate 12V power supply all by itself to supply the C11 speed control power input. That part should be fine....unless I need to plug it in at the neighbor's house to completely isolate it. ;)
The paragraph from the KB manual quoted above is the answer...I think. I would've verified it last night but after an evening of lawn mowing in 100 deg. heat and the appropriate celebratory libation, I was in no mood to joust with magic smoke. ;D
I've had the C11 gnd/0-10V outputs connected to the KB P1 & P2 terminals all along which must be wrong as the KB manual clearly states that it wants to see a 0-7V input at P2 and F- I think what I'll do as a test is to connect a separate 3V source to those 2 terminals and see if I get roughly half-speed at the motor.
Thanks for the heads-up Vogavt, I definitely won't connect to the F+ terminal! :o I'll post my results...good or bad.
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My 12V supply is independent for supplying voltage to the analog input of the c11 board. Still no joy.
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I have my c11 and KBMM-125 using the spindle control just fine. I can pull it apart tonight to see how I wired it up. I do know that I am using a separate dc supply just for the spindle.
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Thanks, that'd be awesome! It'll really help Vogavt and I a lot. ;D
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Absolutely!
And for others benefit a simple schematic would be nice too! Not an electronics type schematic, but a wire from point A to Point B.
Okay, I'll admit it... it's really to help the voodoo electro-magical challenged like me.
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Well, I'm not electrician and it has been a while since I set this up but I will try to help.
Here is the C11. The spindle control is on the bottom right. The black and yellow cables just run to a DB9 port on the box.
(http://i457.photobucket.com/albums/qq295/mrcodewiz/metalworking/G0704/KBMM/6723f6f5.jpg)
The black and red wires from the C11 (for spindle power) run to a jack for this separate wall plug.
(http://i457.photobucket.com/albums/qq295/mrcodewiz/metalworking/G0704/KBMM/15993a74.jpg)
You'll notice the power supply is actually 18V. I know that the KB manual states the supply should be 0 to 10 or something like that but my motor is 110V and when I first set this up, I could not get it to power the motor up to full speed. I spoke with Arturo from CNC4PC and he had me measure the voltage across the KB board with the PWM installed and it came out to more like 15V and in order to get 15V out of those leads, I had to use an 18V supply because there is a slight voltage drop.
Here is a shot of the KB board. The control wires from the C11 are the green/black wires in the heat shrink. They are connected to the F- and P2 leads on the KB.
(http://i457.photobucket.com/albums/qq295/mrcodewiz/metalworking/G0704/KBMM/4c268ca9.jpg)
Now, I don't have my motor wired directly to the KB. I have a g0704 and the original box had a FORWARD/REVERSE switch in place so I just left it (even though I don't use reverse). I believe if you wanted, you could just run the A+/A- directly to the motor. My A+ and A- go into the switch and from there it feeds back out to the motor (2 and 6 in this photo):
(http://i457.photobucket.com/albums/qq295/mrcodewiz/metalworking/G0704/KBMM/P1050631.jpg)
After that it was just a matter of setting it up in ports and pins:
(http://i457.photobucket.com/albums/qq295/mrcodewiz/metalworking/G0704/KBMM/mach3_spindle.jpg)
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Thanks nuc, that confirms the P2/F- hookup as I found in the KB manual.
Question: In the 3rd picture I see the green wire connected to P2 but what's connected to (I assume) the P1 & P2 terminals next to it with the blue & black wires. Is that the 2 wires from the old manual pot? Should they be left connected? I assumed that with computer speed control via C11 the manual pot was supposed to be completely removed??
If they're not the 2 wires from the pot, what are they?
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Hmmm... I think those may be 2 of the pot leads that I forgot to disconnect. I will have to tear it apart again and see. The pot does nothing when I turn it.
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Thanks again nuc, if it's working, please don't mess with it on my account! All I've managed to do now is blow the fuse on my KB and vaporize a track on the C11 board. This thing is killin' me! :-[
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Ouch!
Well, I got my replacement chips in yesterday and got them in changed out in my c11 board. Everything's working as it was before. I now have voltage being changed at the analog output.
HOWEVER, I'm not connecting anything to it until I hear back from Arturo. All I can confirm is the voltage changes as I make varying M3 speed calls.
I've already been down that road of blown traces but not on my c11, just on the KBLC-19M.
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After several emails back and forth with Arturo, I finally have success!
I now have the c11 board working with the KBLC-19M and have full control of spindle speed.
Here's what worked for me (Your Mileage May Vary):
I needed to verify the maximum voltage across Pin 1 and Pin 2 of the KB board. As stated before, I had the KB board wired to a potentiometer. Started out with the KBLC-19M not connected to the c11.
1. With NOTHING but power to the KB board AND manipulating the pot AND checking the voltage across P1 & P2 of the KB board, I read a maximum of 8Vdc. I had the maximum voltage coming out to the c11 board at 10Vdc which may have caused an over-voltage issue and toasted my chip set on the c11.
2. On the c11 board I then set the pot on the analog out to minimum voltage by rotating the pot adjustment screw fully counter-clockwise.
3. Again, WITHOUT the KB board connected to the c11, I powered up the c11.
4. In Mach3, I requested the maximum RPM (M3 S6000 for me) to match with my maximum pulley speed setting (Pulley 1 is at maximum 6000 for me). Measuring the analog output on the c11, I was only able to get the voltage down to 9Vdc. I knew some adjustments were needed in Mach3.
5. Turned the spindle off (M5)
6. In Mach3, under Motor Tuning, I decreased my spindle velocity to 1200 units (it was at 1500 before).
7. Turned the spindle back on & pushed its speed to maximum rpm via Mach3 as in Step 4.
8. I remeasured the voltage out on the c11 and it was then reading 7Vdc.
9. I adjusted the pot on the c11 to read 8Vdc.
10. Turned the spindle off and turned all power off.
11. Disconnected all three potentiometer wires from the KBLC.
12. Connected the P1 from the KBLC to GND (Analog Out) on the c11.
13. Connected the P2 from the KBLC to 10Vdc (Analog Out) on the c11.
14. Said a prayer!
15. Powered everything up - no sparks or flashes!
16. In Mach3, requested various speeds with success.
Hope this helps!
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Thanks, mebbe there is a Santy Clause after all! ;D
I'm wrapped up with other stuff right now but hopefully I can duplicate your success this weekend; Lord willin' and the creek don't rise as my pappy used to say.
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Well I'm back where I started. I got the C11 0-10VDC-out terminal working again by jumping across the vaporized track. Got the KB working by replacing the fuse; the manual pot still works fine. So...the C11 is now workiing up & down via Mach commands and the KB is working normally.
I followed Vogavt's instructions except my KBIC-120 only measured 3.55V across P1/P2 with the pot turned wide open. I commanded 2000 rpm in Mach, set the C11 pot to 3.55V, disconnected the manual pot, hooked up P1 to Gnd and P2 to the analog out on the C11 and did a M3S500 MDI command. No flashy arcs but the motor instantly jerked up to WFO and no amount of Mach fiddling makes a bit of difference.
I guess I'm going to have to get one of the KBSI-5 Barrier Terminal Board Signal Isolators so I can hook up like the manual says to P2 & F-. Anybody know how to isolate the analog out signal from the C11 from the KB without the KB expensive isolator board? I need Mach speed control but don't want any more flashy bangs.
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Dickeybird,
I dare say even though you've managed to get the jumper between the vaporized track, you've more than likely cremated some IC chips. They're relatively inexpensive from Arturo.
I had to replace mine before I could get any control on the speed changes.
Simple investment of time to replace the chips. I did purchase an IC chip extractor from Radio Shack (http://www.radioshack.com/product/index.jsp?productId=2103244) because the first one I pulled flew out of my feeble fingers across the workbench. When I picked it up there were bent legs everywhere. This happenend in the blink of an eye.... pull, pull, nothing... pull some more... umph!...launched the chip into outer space... <Grin>
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I yell & scream at my monitor many times when I search for solutions to problems and find that the threads with my exact problem just die quietly. I guess the OP gets the fault fixed and doesn't bother to post the fix. With that said, here's what I did for a solid fix for my C11/KBIC-120 speed control problem.
I read the KB manual more thoroughly and they stress that the voltage following connection voltage must come from an isolated source such as their KBSI-240D Signal Isolator Board to go between the process control and the KB speed controller. I watched eBay for a while and finally won one for $34.00 shipped. I hooked it up (via P2 and F- on the KBIC-120) as per the manual and every thing works great! I guess I'm too electronically challenged to get my head around Arturo's many & varied instructions re: C11 & C6 speed control hookup. The isolation thing is stressed but (IMO) there's not enough clear, step by step instructions in the C11 manual on how to achieve it.
The KBSI-240D has really nice multi-turn min/max speed pots and a few minutes of fine tuning now has my spindle speed consistently & accurately tracking all speeds I input into Mach. HALLE-FRICK'N-LUJAH!!
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Sounds good! Thanks for posting your resolution. That should help others like you've said.
I have to agree with you on the ridicously poor documentation. Vague and confusing at best. I wonder how many other boards have been toasted. I suppose that's why he sells a set of chips ready to go. Scratching my head going "hmmm" on that one.
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I just finished getting another function to work I couldn't figure out previously. I wanted to be able to switch the spindle back & forth between manual (via potentiometer) and Mach speed control and one of the example schematics in the -240G manual showed clearly how to wire it up. It works!
There is a big difference between the top speed in the 2 modes so I guess it'll require some juggling of the trim pots on the 3 boards to get it right but juggling I can handle....it's the smoke & flashing events I have trouble with. ;D
ps: I got lucky & didn't have to buy a set of chips. ::)