Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: MillMaster on December 26, 2009, 04:20:47 PM
-
How do I change the jog velocity using a MPG? I see on the jog fly out there is a DRO for velocity but I do not see a button for changing the velocity, I have tried typing a different value into the MPG DRO but it does not make any difference.
-
Your MPG should 'jog' an axis according to the speed that you rotate the pulse generator. Set-up in 'Ports and Pins' - 'Encoder/MPG's' should be set according to the MPG and you can also check and calibrate that setting on the 'fly-out'. But set the 'MPG MODE' for 'velocity only' and you should be able to control your jog speed by your rotational speed of the MPG knob.....
Bill C.
-
The two modes I use my MPG in is Velocity and MultiStep. When in Velocity it works as Bill C has mentioned and when in Multi Step each click will move at the increment set in the Cycle Jog Step DRO and it will do so at the speed set in the MPG Feedrate DRO.
Hood
-
Thanks for the input. The MPG was working like a charm until the last engraving program I ran through the machine now when I jog with the MPG in Velocity mode it is about half the speed it was before (really have to spin the wheel fast to obtain the jog speed I had before) and the MPG dro is sitting at 12% (seems like a default always at 12% when Mach is booted up) but it does not make any difference in speed on any value I enter in it. From what I read in Hood's reply the MPG dro is only for Step Velocity is that correct? Just trying to get my head wrapped around why it has slowed down and how to get it back to where it was before.
millmaster
-
Yes the MPG Feedrate DRO should only affect the Step or MultiStep modes and Velocity is controlled by the speed you wind the MPG. I am not sure what the MPG % DRO actually does as I have never experimented with it, mine is default at 5% I think if memory serves me right.
By the sounds of it you are needing to run the calibration utility which you will get from the Function Configs menu. Remember to save after you have run it.
Hood
-
In 'General Config' (General Logic Configuration) check boxes: 'FeedOverRide Persist' and 'Lock Rapid FRO to Feed FRO'. Give those a try. What MPG are you using?
Bill C.
-
Thanks BillC for the tips, I will check those boxes later today. I am using CNC4PC's MPG2 Pendant. I have recalibrated the MPG a couple of times still no change of speed, I am sure I am missing some little check box or setting just a case of tunnel vision right now.
millmaster
-
That's the one I use....Go to 'Ports and Pins' to the 'encoder/mpg' page and set your 'pulse per' to 4 and the velocity to 400 then , backing out - reset. You should see those figures when you choose 'cal'ibrate on the fly-out, then set the MPG Feedrate to about 20.00. And set the check boxes as before.
Arturo says that there should only be one pulse per click but my system shows 4 (quadrature I assume)....?
Should work, but then..... let us know.
Bill C.
-
BillC
I checked the config settings and the boxes were allready checked, so I went to Ports and Pins and found the velocity was set at 260 so I set it to 400 and did a recalibrate that did the trick for getting the speed back, but now I am not able to jog in normal mode via keyboard (and touchscreen), the jog off/on switch in Mach appears to work only while holding down the enable button on the pendant which I never had to do before. Any thoughts on this?
Also does your MPG pendant allow an axis to go in a runaway mode if you are jogging in Velocity mode and release the enable button while turning the MPG wheel, the only way to stop the axis when this happens is to cycle the enable button or hit e-stop. Arturo claims there is a bug in Mach causing the runaway mode.
Millmaster
-
How does the pendant connect to the computer?
Hood
-
Hood
The pendant is connected to port 2 of the smoothstepper via CNC4PC's C22 interface card.
Millmaster
-
BillC
I checked the config settings and the boxes were allready checked, so I went to Ports and Pins and found the velocity was set at 260 so I set it to 400 and did a recalibrate that did the trick for getting the speed back, but now I am not able to jog in normal mode via keyboard (and touchscreen), the jog off/on switch in Mach appears to work only while holding down the enable button on the pendant which I never had to do before. Any thoughts on this?
Also does your MPG pendant allow an axis to go in a runaway mode if you are jogging in Velocity mode and release the enable button while turning the MPG wheel, the only way to stop the axis when this happens is to cycle the enable button or hit e-stop. Arturo claims there is a bug in Mach causing the runaway mode.
Millmaster
Apparently you must have the step switch on the pendent set to X1000 or an axis will run away. That switch is accidentally moved when I'm attempting to change an axis to jog and must catch the machine with a reset or hold the enable button on the pendent to stop the runaway. I have also mentioned this to Arturo. The step function must be set on the flyout to work the pendent correctly. There are issues with this pendent. I have been around many times with these problems, changed pendents and changed the C22 board but these problems exist. The brains, I believe, are the problem. This computer will freeze on boot-up if the pendent is plugged in to the second parallel port as well.
Bill C.
-
I must add that in spite of the problems with this MPG2 pendent, I use it most all of the time. Although, when setting to very exacting points, I still use the flyout and the keyboard...
Bill C.