Installing duet 3d on stratasys fortus 350 mc machine

[vaibhav123]

Hi I am trying to install duet 3d motherboard on a old stratasys fortus machine 350 mc they have xbr-2910 ac servo motors (https://ibb.co/58B80Xv) on them and the drivers are from company advance motion controls brushless pwm servo amplifier CB12A1C !(https://ibb.co/1G8WfWq) this driver don't have step pulse or dir input signal. How can I control these motors via duet3d

[rjenkinsgb]

@vaibhav123
Those are "Brushless DC" type motors and servos, not stepper motors or drives.

They need an analog control signal from a system that has a position feedback loop, the same as many industrial CNCs.

They are very nice units, but as far as I am aware, they cannot be used as axis drives for a Duet without a separate "intelligent" controller that counts pulses and compares to the feedback position - and I don't know if such a thing even exists.

This appears to be someone's project to do something similar, which could possibly be adapted, taking the command voltage to the existing drive rather than directly controlling the DC motor?
https://hackaday.io/project/178310-stepper-to-dc-motor-conversion

[vaibhav123]

@rjenkinsgb they are not dc motor they are ac servo motor XBR-2910 (part# 1834629030) Specs:

Torque Constant (Kt) : 1.8 in-lbs/ amp

Voltage Constant (Ke) : 19.9 - 23.1 V/KRPM

Rated Voltage : 230 volts

Continuous Speed (no load) : 6000 rpm

Peak Torque : 18.5 in-lbs

Continuous Torque : 6.1 in-lbs

Inductance : 5.8 mH

Encoder count: 2,000 ppr

Encoder Voltage : 5 Vdc

Encoder current: 225 mA
Information source https://sourceforge.net/p/emc/mailman/emc-users/thread/20120714215707.639cb518@Matt/

I am thinking of replacing the motors and it's drive do you think it will save me a lot of trouble shooting, can you recommend any replacement motor and driver for this project?
2. They don't have bed heaters but they have chamber heaters which are again ac more than 1000w 3 of them with ac two blowers. If the community can help me with the motors we can move towards heaters and then the head motors they are also dc . Thanks in advance for you help

[rjenkinsgb]

@vaibhav123
"Brushless DC" motors and drives, not simple DC.
https://en.wikipedia.org/wiki/Brushless_DC_electric_motor

OK, the motor figures translate to approx. 98 oz-inch (0.7nM) continuous and 296 oz-in (2.1nM) peak.

The largest of these NEMA23 motors exceeds that, but the maximum speed is rather lower, 5000pps is only 1500rpm.
https://ooznest.co.uk/product/nema23-stepper-motors/?attribute_pa_model=2303hs200aw-175oz-2-00a&gclid=CjwKCAiAvOeQBhBkEiwAxutUVOLfurThGNxBFSaCWwiqa_EZIMtvfpYA_HbhKqC64rNQCQ-3VJdS5hoCsW0QAvD_BwE

Something like a Duet 6HC could run those direct, or you could use larger motors with separate drivers, with a Duet capable of feeding step & direction to an external drive.

eg. This type, 4nm = 566 oz-in or over 35 in-lb
https://www.cnc4you.co.uk/Stepper-Motor/Nema23-4Nm/Stepper-Motor-Digital-Kit-4Nm-x-3-Axis-Nema23

(Or again a 6HC with 32V supply should be able to run those motors directly & with near the same performance as the separate drivers on 36V, but the external drivers can run higher voltage, so maintain torque at somewhat higher speed).

The downside with any of those is you will either not get the same axis speed, or not get the acceleration, compared the original motors and drives.

What end result you get depends on the existing gearing and how you can make it suit the steppers.

[vaibhav123]

These motors are nema 34 https://www.radwell.co.uk/en-GB/Buy/ELECTROCRAFT/ELECTROCRAFT/XBR-2910/?redirect=true

[vaibhav123]

@vaibhav123 do u recommend any driver that can be clubbed with duet mother bord

[vaibhav123]

@vaibhav123 can have a separate supply for the motors and drives

[vaibhav123]

@vaibhav123 I would rather prefer to define accel with duet 3d

[rjenkinsgb]

@vaibhav123
You can get NEMA34 steppers, but I don't know what Duet / drive system would be suitable.

The people using Duets for CNC control are more likely to be using motors in that size and power range, I believe?

[vaibhav123]

Encoder with stepper motor would give the same performance with leadshine drives what is you opinion?

[rjenkinsgb]

@vaibhav123
These are another alternative, after some more searching!

Drives that accept step & direction signals, but work with BLDC motors!
http://www.leadshine.com/productdetail.aspx?type=products&category=servo-products&producttype=brushless-servo-drives&series=ACS&model=ACS806

They may give you the best of both worlds - Duet interface and the servomotor speed and torque etc.

[vaibhav123]

I think that those motors are over powered for 3d printing because it will never reach half of its rpm it's corexy mechanism

[vaibhav123]

@vaibhav123 I still don't understand why they have a motor that can go up to 6000 rpm

[vaibhav123]

Because the belts and pulleys are similar to a core xy setup

[vaibhav123]

@vaibhav123 update it doesn't have limit switch for xy does have for z axis so it's like prusa stall detection

[rjenkinsgb]

@vaibhav123
Do the CoreXY axis drive belts go directly to the motor pulley, or is there some kind of intermediate gearbox or separate belt reduction between the motor and axis belts?

[vaibhav123]

@rjenkinsgb I can change the motors and drive but I need a recommendation from duet 3d that with expansion board I would have least problems

[vaibhav123]

@rjenkinsgb there is no gear box it is direct with four pulleys for x axis at each corner and 2 for y axis

[vaibhav123]

This post is deleted!

[vaibhav123]

https://postimg.cc/7JZtxcyg this kind