Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: panaceabeachbum on May 20, 2009, 07:31:35 PM
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My apologies for posting a SS related question in the general forum but I was afraid with the limited traffic in the SS forum my post there might get overlooked and I need to turn a bunch of parts tommorow.
I installed a smooth stepper board yesterday and have almost everything up and working nicely, but since the instal Mach will no longer communicate wuth the PLC that operates my tool changer . What do I need to look at or change to get Mach to communicate with the PLC?
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First question, how are you communicating with your PLC
Cheers,
Peter.
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modbus via the serial port , db9 on the back of the pc
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Well I said everything was working properly but I cant get the VFD dialed in or anywhere close to the rpm called out. I can adjust the pulse lenght and get it to turn at the speed called out in one range but then its off by as much as 50% just 100 rpm either side of where its tuned.
I have been using the vfd to control the spindle motor for about a year and had it dialed in within 10rpm of the speed called out across the entire range , from 50 rpm thru 1700 rpm . How or why has the instalation of the ss and drivers caused problems with the output to my vfd?
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Is there a simple setting that will allow me to once again have mach communicate with the PLC after the install of the SS board?
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Sorry cant help with the VFD as I have never used one on either the SS or the PP.
I use a PLC and have never had a problem with it and the SS shouldnt interfere in any way, make sure you have the correct settings for the serial modbus.
Did you make a new profile?
If you are desperate it should just be a 2 second job to hook it back up to the parallel port to get things running then when you have more time you can try again.
Hood
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thanks Hood, i did hook the Parallel port back up and everything is running fine. I did create a new profile for the SS . Do the serial modbus settings need to be reconfigured for the new profile?
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looking at the serial modbus setup page the setting all seem to be the same , between the pp and ss configurations , I am wondering if there is a check box somewhere I have overlooked
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Not that I can remember, the SS should not have any affect on the serial modbus at all.
If you attach your xml I will look and see if I can find a problem.
Hood
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I am trying to attach the xml files and I keep getting an error message stating an attachment with the same name has already been posted, when i rename the xml and attempt to post I get an error message stating I have already posted the message
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maybe this will work
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Just had a thought, have you copied your macros over to the new profiles macro folder?
Hood
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Yep , that was it. Had no idea there would be a new macro folder.
Thanks
Now just to dial in this VFD . Just out of curiousity , what other devices are avail to control a 30hp spindle motor besides the vfd?
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Hey I have had simular experiences, here is how I did the work around.
IN your Ports and PINS: DISABLE your spindle motor output!! (I suspect that the SS is fighting over this with your VFD).
Once you have disabled your Spindle motor output, in PP, then goto "Brains". I am assuming you have an Analog module in your PLC??, I am going to assume it is a 12 bit module, change to your situation.
In Brians Put:
Input spindle percent, DRO(99)->formula: (A*4095) -> (your modbus Serial Plugin ->modbus Config, and Local var termination here). DRO 99 ALWAYS shows 0-1.00 (0-100%) of your current Pully range. Just remember also, for tying in your M3/M4/m5 across the Brians, you will need to make sure that you DO enable "Relay control" of M3/M4, and tie each of them, and limit them to Outputs 1-6. The M3, M4 LEDs will only Lite up if tied to these output ranges, then in Brians, be watching the LED for M3, and on another rung, the LED for M4 to send out to your PLC for dirction. NOTE: Mach3 will take care of "interlocking" M3/4 out from eachother, and also will turn them off on m5 calls.
ALSO: check to make sure that your SS is NOT competing with ANY other IO, that your PLC is using, it WILL win in the battle for IO.
scott
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well I seem to be all dialed in , I followed Gregs spindle setup in this thread http://www.machsupport.com/forum/index.php/topic,9523.10.html and then I ran the spindle calibration routine and its running within 2% accross the board .
I currently have my index pulse attached to my BOB , one leg to gnd the other to pin 14 . I would like to attach to the SS board , which term do I attach to ?
I am not going to bother you for how to attach my qaud spindle encoder with index (yet) but if its pretty simple could you give a basic rundown so I can save it for future refrence. My encoder wiring is listed as follows
lead sig A = A + N
Refrence sig = B + P
Lag Signal B = C + R
N P and R are all listed as GND and I assume B is signal
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Now just to dial in this VFD . Just out of curiousity , what other devices are avail to control a 30hp spindle motor besides the vfd?
Not really, if you have an induction motor a VFD or geabox is the only way and gearbox is what I had and only allows certain fixed speeds so its not the best. Now I have a 12.5KW AC Servo and it is great but unless you get lucky like I did then the price of that would be way beyond what you would like to spend I think, about $12k if I recall correctly, I got mine for about $600 :)
I would imagine you would need a lot less than 30HP if you had a servo as they have constant torque from zero to rated speed where an Induction motor loses torque as the VFD slows it down so more HP is needed in the first place, or at least that is what I have found.
Hood
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Dont think you will be able to fit that encoder up, looks like its not TTL :(
Hood
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Looking again at what you wrote it could be a single ended encoder with A and B channels and C being the index, you would have to check it out with a scope or if you have a model number the manufacturers site may have more info.
Hood
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I have looked it up on the renco sight and its a std qaud encoder with index , I actualy had the index hooked to my breakout board last year and it seemed to work fine . I have gone back to the slotted disk since as there was some concern the pulse might not be long enough for the current combination to read accuratley.
On the subject of my current slotted disk and index pulse , how do i go about attaching it to the smooth stepper board?
I am using the c3 index pulse board from cnc4pc
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If it is a differential index then connect to the differential connections on Port 3 of the SmoothStepper, if you power the encoder from a source other than the SS you will have to make sure you have the 0V linked so that the SS has something to reference to.
At this time the SS only uses the Index pulse so there is no benefit to connecting the A and B channels.
Hood
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hooking it up now , fingers crossed
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You can connect that to any input you wish whether on Port 1, 2 or 3 of the SS, it is only if you have a differential input, and want to use it, that you need to use Port3.
Whichever you connect it to you just set the Index in Mach to that port and pin just as you did when using the parallel port.
Hood
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much thanks , seems to be working like a champ
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:)
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just cut the first half a dozen test threads and they look just perfect