Build thread: Sharp TMV Acu-Rite MillPWR to Centroid

[CentroidFrog]

That control panel looks SO clean, well done.

[RichieP_MechE]

I decided to shamelessly copy your design.

If I get the time, I will try to pull together the CAD and make a little design package for it to share with the community here.

[RichieP_MechE]

Quick update on progress:

I got my VFD wired up and functioning with the VCP controls, then got my feet wet with some PLC programming to get the physical control panel spindle controls also working, as well as all of the axis zero buttons.

Next will be to get the Manual mode functioning - I have contactors that are normally closed on the servo drive outputs (though these are currently bypassed, drives are currently wired directly to the servos). They will disconnect when the manual switch is engaged to allow easy operation of the handwheels (if connected to the drive, there is significant resistance from from the servos dumping power back into the drive). I will take my chances for now with back EMF from the disconnected motors not having anywhere to go.

First will just to get basic output on/off working based on switch position, then gradually add in additional logic - I want to automatically turn the drive enable off and also set the spindle to manual mode. Finally will be adding some safety logic so that the contactors don't disengage if the switch is accidentally flipped if the machine is not idle/in the middle of running a program.

[RichieP_MechE]

First will just to get basic output on/off working based on switch position, then gradually add in additional logic - I want to automatically turn the drive enable off and also set the spindle to manual mode. Finally will be adding some safety logic so that the contactors don't disengage if the switch is accidentally flipped if the machine is not idle/in the middle of running a program.

So I got 2 of 3 desired functions for my auto/manual control mode switch working - It toggles the output and sets the spindle to manual mode. I can't seem to find the right output or variable to set to turn Axis Enable to off. Any help from the PLC experts out there?

[RichieP_MechE]

So I got 2 of 3 desired functions for my auto/manual control mode switch working - It toggles the output and sets the spindle to manual mode. I can't seem to find the right output or variable to set to turn Axis Enable to off.

Upon further investigation, I found that if might not be possible for the PLC to set the axis enable bits (I came across this in a pdf somewhere that I currently cannot find).

At any rate, I came up with a way to more or less do what I want by utilizing a bit more hardware. I routed each axis enable output through the normally closed side of an output relay. Added a stage to my PLC program that, when the mode selection switch is set to manual mode, opens the output relay contacts which then puts the drives into standby mode, then after a 1 second pause, opens the contactors on the drive outputs to disconnect the motors. Putting the selector switch back to auto mode performs these same steps in reverse.

One thing I noticed is that the 1 second delay seems to be inconsistent - observing the relay lights, there are definitely have been occasions where they switch nearly simultaneously. I'm wondering if there is an issue with how I coded it - see below.

Code: Select all

;=============================================================================
					AutoManStage ;RichieP wrote this
;=============================================================================
;When the Auto/Man switch is set to Man mode, the spindle is set to manual 
;control, Axis 1 and Axis 2 are disabled, and after a pause of 1 second, the 
;motor contactors are opened.
;
;When switching back to Auto Mode, the motor contactors are closed first, then
;after a pause of 1 second, Axis 1 and 2 are enabled

IF ModeSw THEN 
	RST SpinAutoModeLED, 
	SET Axis1Disable,
	SET Axis2Disable,
	ManualModeDelay_T = 1000, SET ManualModeDelay_T
IF ModeSw && ManualModeDelay_T THEN
	SET AutoManMode, RST ManualModeDelay_T
IF !ModeSw THEN 
	RST AutoManMode, 
	ManualModeDelay_T = 1000, SET ManualModeDelay_T
IF !ModeSw && ManualModeDelay_T THEN
	RST Axis1Disable, 
	RST Axis2Disable, 
	RST ManualModeDelay_T

[cncsnw]

Your one-second timer is continuously activated by the "IF ModeSw ..." and "IF !ModeSw" blocks, so whenever you actually change the switch position, the timer is already running and the accumulator could be anywhere between 0 and 999.

You probably should use a PD (positive differential, a.k.a. one-shot) to only start your timer in the scan where the switch is turned on, or turned off.

[RichieP_MechE]

Your one-second timer is continuously activated by the "IF ModeSw ..." and "IF !ModeSw" blocks, so whenever you actually change the switch position, the timer is already running and the accumulator could be anywhere between 0 and 999.

You probably should use a PD (positive differential, a.k.a. one-shot) to only start your timer in the scan where the switch is turned on, or turned off.

Ok, this is what I was missing. Thanks!

[RichieP_MechE]

Got limit switches in place the other day and they are functional. I ended up reinstalling CNC12 as some wizard settings weren't saving even though I had enabled the wizard to work along with my custom PLC program. Will add all of my custom code back later, looking to just get the CNC functionality working properly for now.

I did set up the quill as a manual Z-axis according to TB292. One issue I'm having is being able to zero the Z-axis (which is now represented as the @ symbol). I think I have to edit a macro for this to work but not sure which one? I wasn't able to find set_part_all_zero.cnc or set_part_axis_zero.cnc. See screenshot below for the error from trying to set the zero on manual Z.

[tblough]

You can zero the quill DRO by using MDI and entering M26/M and pressing cycle start.