[j_sheley]

I ask for the help of CNCzone’s forum members to help me find the value of a motor control project idea.

I value the opinion of people who are knowledgeable in machine control. Many of CNCzone’s forum readers (i.e. you) have experience a 3axis mill, 5 axis mills, or a 3D printer. What I would like from CNCzone’s forum is an idea if my hardware control design is worth the time, effort, and money to develop.

My basic idea is to relocate the motor control (control signals, firmware, and power supply conditioning) from a centralized box to each motor. From an external hardware perspective, I want to replace the central control box and multiple cable schemes with a single cable.

(see image titled “proposed_3_axis_design.PNG”)


What type of cable to use?
A USB-A cable (5 ampere rated) should work for a NEMA-23 motor. I do not want to use USB signals, just the USB-A cable design. A HVAC cable should work for a for NEMA 34 motors. HVAC cables have monstrously large amperage ratings. Both USB cables and HVAC cables have provisions for power and one “LVDS” (digital) signal pair.( half-duplex)

Which type of cable will not work:
An “Ethernet” cable design is not viable due to amperage requirements of “NEMA 23” and/or “NEMA 34” motors. Ethernet cables are designed to propagate high speed AC signals not convey large currents.




The basic benefit(s) for the end customer:

1. Vastly simplified motor connection(s). Power and control are combined in single cable. No central box with multiple cables.
2. Simple MODBUS type expansion upto 128 control nodes (motors, end stops, probes, coolant jets, ect). Just configure one 7 bit DIP switch for each control node with a small screw driver.

(see image titled “DIP_switch.PNG”)

1. Cheap, ubiquitous, commercially available replacement parts. (USB cables, HVAC cables, USB to RS485 converters, power supply)

Basic questions for CNC zone readers:
Does the above described product exist on the market?
Do the above benefits sound appealing?
If this is a good idea, then which motor should I develop first “NEMA 23” or “NEMA 34”?
Is the smaller NEMA 23 motor relegated to “niche” hobby markets?


Please share your constructive thoughts with me.
If you know of a forum better than CNCzone , then please tell me.