Messages

301

General Mach Discussion / Re: I Need a macro written will pay.

« on: February 01, 2018, 08:34:40 PM »

I don't have a link handy but you can search this forum for Mach 4 Teach File and find it pretty quick I think.

302

Mach4 General Discussion / Re: Help with Mach 4 controlling a PLC for tool changes.

« on: February 01, 2018, 08:29:37 PM »

 

303

General Mach Discussion / Re: I Need a macro written will pay.

« on: February 01, 2018, 06:41:13 PM »

If your interested in trying it with Mach4 I posted a teach file script for it not too long ago that may get you almost where you want to be. Would just need to get the register value you will be using for the analog input from the laser instead of Z axis position And automate some moves between readings I think.

304

General Mach Discussion / Re: Large Calibration Numbers- Opinions?

« on: February 01, 2018, 05:44:15 PM »

 

305

Mach4 General Discussion / Re: Help with Mach 4 controlling a PLC for tool changes.

« on: January 31, 2018, 08:27:04 PM »

Yup, then set your stuff in motion in the PLC with the C bits.

If you do it right you can drive the tool changer from 2 sources. Inputs (like push buttons) and modbus (changing bits from Mach). However your right may not require it to be driven from multiple sources so the rest of this may just be noise you have no need to hear....

Input ********* comes on, C bit ********* goes high.

In ladder, if C bit goes high, do your thing, turn that C bit off and turn on the next C bit so it does its next thing. But what happens if that C bit you just turned off is still high because the input is still on? Well, you need to check its state before you do the next thing. But you know if you check in the next rung of the PLC ladder the bit is off because you just turned it off. The ladder will turn the bit back on but not until it gets back up to the top again (which takes about as long as your scan time...... so its real quick) where the input turns that C bit on.

You get around things like this by having a register you write to for stages. Its value is used to check that things are right before doing the next step or stage. Can be a lot to think about but can be worth the effort too.

Another way to do it is have a ladder for each mode (manual/auto). One wont work if the other is on. Modbus ladder is driven by C bits, manual ladder is driven by inputs.

Lots of ways to do it. Just have to play with things until you get it working just like you want it to. When it does that, its right.

306

General Mach Discussion / Re: Large Calibration Numbers- Opinions?

« on: January 31, 2018, 07:54:53 PM »

Hmmm, 16 teeth per rev and 8 teeth per inch on the rack = roughly 2 inches (8 teeth per inch) per rev.

Now you need to know how many pulses you have to send the motor for it to rotate 1 revolution. Your micro steps will be considered in this part. And, you need to know the actual number, not guess and change until it moves one rev. No telling how many steps it skipped moving that one rev when guessing like that.

If your steps per do == 19,000 and your motion device can support the frequency of pulses, then nothing wrong with it. There are lots of systems running higher resolution than 19,000 steps per inch.

Just some numbers for you........

19,000 steps per inch X 12 inches = 228,000 pulses per foot

228,000 X 160 feet per minute = 36,480,000 pulse per minute

36,480,000 \ 60 seconds = 608,000 pulses a second or 608 kHz

Depends on what your using to generate your pulses but some external motion devices can reliable send millions of pulses a second (MHz).

The parallel port tops out at about 50kHz or less in most setups.

307

Mach4 General Discussion / Re: Help with Mach 4 controlling a PLC for tool changes.

« on: January 31, 2018, 12:55:17 PM »

I like the second part of your post Brett, all the more reason to free up that "Y".

Yup, it does add some complexity to the ladder in the PLC but it does work nice. On some machines its not as big a benefit. But if the tool changer is attached to the gantry and the gantry has a 40 foot travel being able to do something like disable Mach (which puts the tool changer in the PLC in manual mode) and then work that tool changer with the manual tool change buttons attached to the gantry can be worth a lot over the life of a machine. On small machines its still nice to free up IO. Either way, in almost all cases its best to do things as efficient as possible.

308

Mach4 General Discussion / Re: Help with Mach 4 controlling a PLC for tool changes.

« on: January 31, 2018, 11:22:57 AM »

I can't speak for Chads logic so can't say why he did it like that. I bet he explains it somewhere though. Might be he fires a physical output of the PLC from mach to start the tool change and when tool change is finished it turns that output off, telling Mach the tool change finished. This manual link could act as a pseudo watchdog in a way too...... maybe, just thinking out loud.

Yup, I would have the top section of my ladder setting the state of bits I could get and set through modbus. The bits would mirror the physical IO states. Then I would drive the outputs and read the inputs in Mach over modbus by changing or reading those bits. Hope that makes sense. This enables you to drive the tool changer through physical inputs or inputs over modbus from Mach.

309

Mach4 General Discussion / Re: Help with Mach 4 controlling a PLC for tool changes.

« on: January 30, 2018, 10:54:58 PM »

 

310

Third party software and hardware support forums. / Re: Linkage Mechanism designer and simulator.

« on: January 30, 2018, 09:55:24 AM »

Thats neat! Thanks for sharing Tweakie!