Epilog Rotary Attachment - Technical Help needed with debug

[Karl Ladin]

After having my used Epilog Mini for over 2 years I decided to purchase the rotary attachment. I found a "almost new" used one and purchased it. It's one with the Lin Engineering stepper motor(5609-11-01RO). I was disappointed to find that it did not work on my machine. At this point I did not know if it was the stepper motor or something in my Epilog Machine. I searched the internet for the motor specs and found the method to test the stepper motor with a 9v battery. The test appeared to indicate that the unipolar stepper motor was good. I contacted Epilog Technical Service for help and was informed that a new stepper motor was $126.54. I told them that I would like a pinout of the motor molex connector and the matching machine connector and I received the very unhelpful picture of the rotary plug. Nothing technical... just a picture. I then asked for a schematic of the motor driver circuitry. More useless help. "I don't have those and I don't think I could sent them out.... Motor is 126.53." Is there someone out there that could help me debug this problem? From my poking around the electronics... I believe that the rotary stepper is driven by one of the LMD1845(Full Bridge Motor Driver). I assume when the rotary is attached the y-axis bridge is switched to drive the stepper motor of the rotary. It's output appears to be switching(stepping) when the rotary is working. Is the rotary stepper motor run in a unipolar mode or bipolar mode? I'm stuck.

[Kim Vellore]

Karl,
When you say it is not working on your machine what is happening?, does the machine know the motor is connected. You can tell that by the home position when it powers up. Does the motor move or does it appear totally dead? does it power up (ie locked in position) and does not move?
Kim

[Karl Ladin]

The machine knows the rotary attachment is there. It moves the head above the zero position on the rotary. The stepper motor does not turn. When the machine is in the standby state the motor is locked. If I put my finger on the motor pulley when the epilog is operating I can feel it pulse, but no rotation. I tested the stepper motor with the rotary removed and it did rotate. I wired it in a unipolar configuration for the test. I really don't think the motor is bad. Either the pins are wired wrong or the motor driver(s) are not getting good inputs or the drivers are just bad. If I had a schematic they would be so much easier for me.

[Bill George]

Is the machine a servo motor or stepper model? I though Epilogs were all servos.

[Jeanette Brewer]

Unless you purchased the rotary attachment from a Zing or Fusion owner, the rotary attachment will work on your Mini. Presuming it's not a Zing or Fusion attachment, contact tech support tomorrow and they'll get you fixed up.

303-215-9171
tech at epiloglaser dot com

[Karl Ladin]

The motor is a stepper motor. (not a servo)
I am almost positive that this rotary attachment is the Helix/Mini type. and yes... I contacted Epilog tech support. They seem intent that I need to buy a replacement stepper motor. I do have experience with debug/repair of electronic devices. I was hoping that someone would have a schematic of that circuit or some experience debugging this unit.

[Bill George]

The motor is a stepper motor. (not a servo)
I am almost positive that this rotary attachment is the Helix/Mini type. and yes... I contacted Epilog tech support. They seem intent that I need to buy a replacement stepper motor. I do have experience with debug/repair of electronic devices. I was hoping that someone would have a schematic of that circuit or some experience debugging this unit.

Yes I understand you have a stepper motor, but I thought Epilogs were all servos, in fact the Epilog website says the Mini's had high speed servos, Here> https://www.epiloglaser.com/products...rvo-motors.htm

As you well know if the controller is set up for a servo, stepper motors will not work.

[Karl Ladin]

Servo motors drive the X and Y axises. I believe the Mini/Helix rotary attachment uses a stepper motor(either a Vexta PH-265M-33-C9 or a Lin 5609S-11-01R0).
Can someone verify that?

[Kim Vellore]

Karl,
Here are the stepper connections on the connector I got from Dave long time back.
The wire colors are standard for stepper motor, this is a six wire motor
http://www.linengineering.com/resour...nnections.aspx

Kim

[Karl Ladin]

I'd like to thank everyone for helping out. It turns out that the rotary stepper motor is driven by a pair of Allegro A3953 (Full-Bridge PWM Motor Driver), NOT the LMD1845(Full Bridge Motor Driver). I traced it out. (The two LMD1845 chips drive the X and Y axis servos.) The A3953 is discontinued and is replaced with the A4973. The A4973 is a direct replacement. Carefully, I repaired my control board with the new chips and I now have a working rotary.
Bottom line... I sure wish Epilog Technical Support was more technical. I could've probably debugged the problem in a tenth of the time if they could've given me a schematic or even some useful help. I knew very early that the stepper motor was good but support seemed to think a new one was the only solution. I know that Epilog support is in business to get customers up quickly, but buying replacement parts that aren't needed is not good support. If a simple meter test could've determined that the control board had a problem, I would've probably spent the big bucks and bought a new board. Since I was pretty much on my own I took the chance and repaired it for not much money but plenty of time. Is Epilog's technical support consistent with the other major companies? I'm in the early stages of looking for a new larger bed, more power laser. Right now I'm not too happy with Epilog's Technical support.