Another DYN4 and Acorn Losing Steps Issue

[Black Forest]

DMM is using it's customers to troubleshoot their products instead of doing due diligence an testing in house.

When I have mentioned on here to go with either ClearPath or Delta products Marty gets in a huff and tells me this is not the place to discuss. When I mentioned that you can buy Delta products nearly for the same price as DMM he goes on about buying from China, bla bla bla, no service, etc.. Well guess what DMM is a Chinese manufacturer and you all have seen the issues with their products and their service. Now Marty will extol their products and say he has no problems, but others sure are having problems. One just has to read this forum to know about the problems.

How many on here have reported hardware failures from ClearPath or Delta? How many have had to send back ClearPath products because they were defective?

There is absolutely no question that Marty is a big help on this forum. He is a wizard for sure. I just wonder why he is always defending DMM.

[cbb1962]

I don't know Marty, I've never messaged him, and I've never even seen a DMM product in real life.

But I do know this: To bash DMM and Marty isn't right!

I have certain products that I support because I've had good luck with them and I recommend them a lot! Just like Marty.

Slodat stated that the drives work perfectly with the DMM software. This is a specific interface of the DMM product to the Acorn. Who has the burden of testing??? If DMM only sold drives to be connected to the Acorn then it would be DMMs problem, but that is not the case.

Marty has installed many machines with DMM and has had Zero/Minimal issues, Slodat and others have had major issues. Don't bash Marty. Can DMM test for every potential situation???

The purpose of this forum is to help one another, not bash each other.

[martyscncgarage]

DMM and Centroid both have been in business for years. As with any other company, if they put out inferior products, did nothing to improve or correct them, they wouldn't be in business.

They can't be held responsible for how the people use thier products.

Users are expected to use best wiring practices. In the DIY environment, that's a mixed bag.

I am just like you guys, I am not a professional. By trade, I am electrician, I spent my career working on Traffic Signal Control System. I've been doing CNC for over 15 years. I have basic electronics experience but do not have board level experience.

I use what works for me, that is based on personal experience and customer support I am given. Both DMM and Centroid have met that criteria in my experience. I spend a lot of time and effort testing hardware and working with the manufacturers to improve their products.

No one needs to defend me. I'm content doing the best that I can, and in the past, I am very willing to admit when I am wrong, made a mistake or discover an issue. I try to replicate the issues and document them before contacting the vendors, showing them how I found the issue and how to make it repeatable. Then have to leave it up to them to follow up to do their own testing.

Open loop and hybrid closed loop systems (such as Acorn and any drive/motor using encoders) are still open for issues such as being discussed here. The only way to eliminate that, is to go with a true closed loop system (Oak or All in One DC). Acorn has no feedback to know exactly where the machine/motor position is. It just sends out a signal and leaves it to the user to send those signals to the drive/motor.

I also mention that collectively, we can work together to try and identify why the issue is occuring, to help remedy and improve the products. (IF you so choose) I personally haven't run into the issues you guys have. I am off for about a week and when I get back I will try and spend reasonable period of time trying to recreate the issues you guys are having. Since its the signal between Acorn and the drive, it should happen with any drive. not just DMM.

SO, the most productive thing to do, is to lets work together to duplicate the issue and then see if working with the vendors, we can figure out what can be done to resolve it.

Putting an encoder cable from the drive's encoder port to the encoder port on Acorn (as demonstrated by Terry Ruppe of Arrow Controls, who specializes in industrial control retrofits and as I recently demonstrated) does provide visual feedback to see if what Acorn commanded is what the drive did, and using its encoder provide feedback back to Acorn. If there were lost or gained steps between the two, it should show up on the DRO. Has anyone else with the current issue, done this yet?

Marty

[slodat]

I effectively did the same thing by using the DMM software to read absolute encoder position. I posted my results. There has been no real dialogue about what I observed..

I’m not losing encoder counts since I changed to the DB25 step/direction. I think you need to up the resolution and speeds to where I am in order to see the issue.

I am very happy with the customer service I’ve received from DMM. I’m not mad that I had a DOA motor. They took care of it immediately.

I do feel strongly there is a (tiny) market for a proper connection setup between DMM drives and Acorn using the DB25 and 5v. DMM is not interested in making it. Because “it’s too complicated”, which I find weird.

[DannyB]

"Too complicated" -> Reading your setup, you are trying to get 250k+ steps/second over a non-differential wiring scheme of significant length.
Additionally, the pulse width is pretty short regardless of actual steps/second.

This is certainly theoretically possible to do, but it is going to be finicky.

I expect most of their customers are keeping it under a couple feet of cable.

[slodat]

Huh?? The cable length between acorn and DYN4 is about 2 feet. There is no loss of steps between the DYN4 drive and the motor. It is working great, now that I'm on the DB25 step/direction...

[mick41zxr]

Guys,
No way was this about bashing any body or any company, I am super happy with my DMM setup.
The auto tuning & monitoring software are invaluable. The performance is substantially superior to both steppers & closed loop steppers (in my limited experience) to make them worthwhile. I have the machine to a point where I am running out of pulses & either have to alter setting 968 ?? (have tested up to 800 inch rapids) or change the gearing to get faster rapids. A lot of this is discovering the little tweaks to get everything running smoothly & reliably, I thought that was the purpose of the forum.
Thanks,
Michael

[DannyB]

Huh?? The cable length between acorn and DYN4 is about 2 feet. There is no loss of steps between the DYN4 drive and the motor. It is working great, now that I'm on the DB25 step/direction...

Sorry, i must have misread that thread! It looked like you have a cable that went pretty far from the box to the driver.