Messages

31

General Mach Discussion / Re: spindle speed via modbus

« on: November 10, 2010, 11:14:48 AM »

Peter,

Thanks a lot!!
I´ll take a deep look at that. It seems to be what I need.

32

General Mach Discussion / Re: spindle speed via modbus

« on: November 09, 2010, 08:07:37 AM »

Yes, the inverter uses modbus and I know how to set it up for this.
I don´t know how to setup Mach3 to give this information tho the inverter via modbus.

33

General Mach Discussion / spindle speed via modbus

« on: November 09, 2010, 07:46:39 AM »

Is it possible to control the spindle speed using a frequency inverter and sending the speed information from Mach3 via Modbus?

I know I can use PWM or pulse/dir signals, although I´m running out of available pins, so I thought using modbus for this.

34

Machscreen Screen Designer / Modbus DRO

« on: November 08, 2010, 08:02:21 PM »

I´m working in a resin dispensing machine that uses Mach3 and has  a PLC to control some machine functions.
One functions the PLC controls is a variable speed resin pump. I need to control the pump speed from within a Mach3 screen.
The idea is to have a DRO in the screen with the pump RPM and be able to send this value to the PLC via modbus. The RPM value should be a discrete value going from 1 to 100.

I understand how to use modbus for bit signals (like a sensor on-off status) but I don´t get how to use it for discrete values.

Any leads to point me in the right direction would be greately appreciated.
Thanks.

35

General Mach Discussion / Define variables and transmit them via Modbus

« on: November 03, 2010, 12:48:27 PM »

Hi all.
I´building a resin dispensing machine that uses Mach3 and also has PLC to control several functions.
One of the functions controlled by the PLC is a variable speed pump. The PLC controls the start, stop and the speed of the pump.
I need to be able to setup a speed value within Mach3 screen with a DRO in a custom screen and then send that value to the PLC via Modbus.
I already have Mach3 and the PLC talking over Modbus and I can send back and forth PLC and Mach3 I/O signals, although I have no idea about how to send a discreet value (like 1000) neither how to store that value within Mach3.
One option I thought possible is to store this value in Mach3 could be spindle speed, although I have no idea about how to send this via Modbus.

36

General Mach Discussion / Re: Different use of Mach3 (dispensing)

« on: June 09, 2010, 09:47:32 AM »

I found what was wrong.
The pulses out of the PLC were too wide (too much time) and that´s why the motor was not running smooth.

Now I only need to decide how to control the pump from Mach3.
I thought about using the Z axis direction pin, so when the Z axis go down the pump should start and when the Z axis goes up to stop. It´s like if this was a mill, when the tool goes down it means it´s working on the material.
The problem I also found is if I stop the program for some reason (or if I need to run it step by step), the pump will keep dispensing resin even when the axis are not moving.

Anybody used Mach3 for a laser cutting machine? there should be the same problem there to start and stop the laser beam.

37

General Mach Discussion / Re: Different use of Mach3 (dispensing)

« on: June 05, 2010, 03:22:28 PM »

While testing this I run into another problem (yet another one in the hugelist).

I connected the motor driver PULSE and DIRECTION signals to PLC outputs and started making some tests.
I keep the DIR signal unchanged and send ON-OFF sequences to the PULSE pin to make the motor turn.

When doing this, first of all, the motor makes loud noises and shakes like somthing is about to brake each time it moves, this happens even if I send a single pulse to the driver. Also, if I send a series of pulses the motor turns a few steps in one direction and then it either misses a couple steps or it turns one or two steps in the opposite direction.(!?!?!?)

Of course the motor&driver works perfectly when it´s directly controlled by M3 through the PC parallel port.

I´m not sure what may be different between the pulses M3 creates and the ones from the PLC.

38

General Mach Discussion / Re: Different use of Mach3 (dispensing)

« on: June 03, 2010, 03:53:08 PM »

I think I just came accross a neat solution.
My machine besides Mach3 also has a PLC incorporated.
What I´m testing at this very moment is to use the DIR pin of Z axis to control when to start and stop the pumping. I use the signal transitions from on to off and viceversa to start and stop the pump.
The pulses are generated by the PLC in my case.
My goal is to get something that will not require any hand codding at all. The GCode will come from Lazycam.

39

General Mach Discussion / Re: Different use of Mach3 (dispensing)

« on: June 03, 2010, 01:47:00 PM »

George,

I´m finally working on my domes machine and it´s almost done, although I still have some open issues left.

How do you control when to start and stop resin dispensing? Do you need to hand code that or Artcam does the job for you from the drawing??

40

General Mach Discussion / Re: Different use of Mach3 (dispensing)

« on: September 09, 2009, 07:57:32 AM »

George,

I tried what you said about drawing lines and it seems to work even with LazyCAM!!!

How do you pump the resin? I thought about using pneumatic cylinders although I´d need a way to stop dispensing to refill the cylinders from time to time.